{"pageNumber":"359","pageRowStart":"8950","pageSize":"25","recordCount":16446,"records":[{"id":70023202,"text":"70023202 - 2000 - Timescales for migration of atmospherically derived sulphate through an alpine/subalpine watershed, Loch Vale, Colorado","interactions":[],"lastModifiedDate":"2018-12-12T10:27:51","indexId":"70023202","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Timescales for migration of atmospherically derived sulphate through an alpine/subalpine watershed, Loch Vale, Colorado","docAbstract":"<p><span>Sulphur 35, a cosmogenically produced radioisotope with a short half‐life (87 days), was measured in snowpack during 1993–1997 and at four locations within the Loch Vale watershed during 1995–1997. The four sites include the two main drainages in the watershed, Andrews Creek and Icy Brook, a small south facing catchment flowing into Andrews Creek (Andrews Spring 1), and a similar north facing catchment flowing out of a scree field into Icy Brook (Spring 19). Concentrations ranged from a high of almost 50 mBq/L for a sample from Spring 19 in June 1996 to a concentration near the detection limit for a sample from Andrews Creek in April 1997. Sulphur 35 concentrations were normalized to sulphate (as mBq/mg SO</span><sub>4</sub><sup>−2</sup><span>) and were decay‐corrected to a Julian day of 90 (April 1) for each year. Snowpack had the highest<span>&nbsp;</span></span><sup>35</sup><span>S concentration with an average concentration of 53 mBq/mg SO</span><sub>4</sub><sup>−2</sup><span>. Concentrations in the streams were much lower, even when corrected for decay relative to JD 90. The large<span>&nbsp;</span></span><sup>35</sup><span>S concentrations found in Spring 19 were the result of increases in concentration due to sublimation and/or evapotranspiration and were lower than snowpack when normalized to sulphate. Using<span>&nbsp;</span></span><sup>35</sup><span>S concentrations found in snowpack as of JD 90 as a beginning concentration, the fraction of sulphate in streamflow that was derived from atmospheric deposition within the prior water year was estimated. For Icy Brook and Andrews Creek the fraction of the sulphate in streamflow derived from that year's snowpack and precipitation was low prior to the beginning of the main spring melt, reached a maximum during the period of maximum flow, and decreased as the summer progressed. A calculation of the seasonal flux indicated that about 40% of the sulphate that flowed out of the watershed was derived from atmospheric sulphate deposited during the previous year. This suggests that more than half of the sulphate deposited in the watershed by atmospheric processes during the previous year was removed during the following summer. Thus sulphate retention in alpine watersheds like Loch Vale is very limited, and changes in sulphate deposition should be quickly reflected in stream chemistry.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1999WR900276","usgsCitation":"Michel, R.L., Campbell, D.H., Clow, D.W., and Turk, J.T., 2000, Timescales for migration of atmospherically derived sulphate through an alpine/subalpine watershed, Loch Vale, Colorado: Water Resources Research, v. 36, no. 1, p. 27-36, https://doi.org/10.1029/1999WR900276.","productDescription":"10 p.","startPage":"27","endPage":"36","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":479299,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/1999wr900276","text":"Publisher Index Page"},{"id":233479,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","otherGeospatial":"Loch Vale","volume":"36","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb3e2e4b08c986b326047","contributors":{"authors":[{"text":"Michel, Robert L. rlmichel@usgs.gov","contributorId":823,"corporation":false,"usgs":true,"family":"Michel","given":"Robert","email":"rlmichel@usgs.gov","middleInitial":"L.","affiliations":[{"id":148,"text":"Branch of Regional Research-Western Region","active":false,"usgs":true}],"preferred":true,"id":396818,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Campbell, Donald H. dhcampbe@usgs.gov","contributorId":1670,"corporation":false,"usgs":true,"family":"Campbell","given":"Donald","email":"dhcampbe@usgs.gov","middleInitial":"H.","affiliations":[],"preferred":true,"id":396817,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Clow, David W. 0000-0001-6183-4824 dwclow@usgs.gov","orcid":"https://orcid.org/0000-0001-6183-4824","contributorId":1671,"corporation":false,"usgs":true,"family":"Clow","given":"David","email":"dwclow@usgs.gov","middleInitial":"W.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":396820,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Turk, John T.","contributorId":53363,"corporation":false,"usgs":true,"family":"Turk","given":"John","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":396819,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022258,"text":"70022258 - 2000 - Drainage-basis-scale geomorphic analysis to determine refernce conditions for ecologic restoration-Kissimmee River, Florida","interactions":[],"lastModifiedDate":"2022-09-22T15:01:46.5241","indexId":"70022258","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Drainage-basis-scale geomorphic analysis to determine refernce conditions for ecologic restoration-Kissimmee River, Florida","docAbstract":"<p>Major controls on the retention, distribution, and discharge of surface water in the historic (precanal) Kissimmee drainage basin and river were investigated to determine reference conditions for ecosystem restoration. Precanal Kissimmee drainage-basin hydrology was largely controlled by landforms derived from relict, coastal ridge, lagoon, and shallow-shelf features; widespread carbonate solution depressions; and a poorly developed fluvial drainage network. Prior to channelization for flood control, the Kissimmee River was a very low gradient, moderately meandering river that flowed from Lake Kissimmee to Lake Okeechobee through the lower drainage basin.</p><p>We infer that during normal wet seasons, river discharge rapidly exceeded Lake Okeechobee outflow capacity, and excess surface water backed up into the low-gradient Kissimmee River. This backwater effect induced bankfull and peak discharge early in the flood cycle and transformed the flood plain into a shallow aquatic system with both lacustrine and riverine characteristics. The large volumes of surface water retained in the lakes and wetlands of the upper basin maintained overbank flow conditions for several months after peak discharge. Analysis indicates that most of the geomorphic work on the channel and flood plain occurred during the frequently recurring extended periods of overbank discharge and that discharge volume may have been significant in determining channel dimensions.</p><p>Comparison of hydrogeomorphic relationships with other river systems identified links between geomorphology and hydrology of the precanal Kissimmee River. However, drainage-basin and hydraulic geometry models derived solely from general populations of river systems may produce spurious reference conditions for restoration design criteria.</p>","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(2000)112<884:DGATDR>2.0.CO;2","issn":"00167606","usgsCitation":"Warne, A., Toth, L., and White, W., 2000, Drainage-basis-scale geomorphic analysis to determine refernce conditions for ecologic restoration-Kissimmee River, Florida: Geological Society of America Bulletin, v. 112, no. 6, p. 884-899, https://doi.org/10.1130/0016-7606(2000)112<884:DGATDR>2.0.CO;2.","productDescription":"16 p.","startPage":"884","endPage":"899","costCenters":[],"links":[{"id":230670,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Kissimmee River, Lake Kissimmee, Lake Okeechobee","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -81.18690490722655,\n              27.800817328100297\n            ],\n            [\n              -81.19102478027344,\n              27.870644599673355\n            ],\n            [\n              -81.20201110839844,\n              27.877321374551116\n            ],\n            [\n              -81.21986389160156,\n              27.93254072134666\n            ],\n            [\n              -81.22055053710938,\n              27.955591004642553\n            ],\n            [\n              -81.29539489746094,\n              28.002283068261377\n            ],\n            [\n              -81.32011413574219,\n              27.99803917062052\n            ],\n            [\n              -81.30569458007812,\n              27.977423576428517\n            ],\n            [\n              -81.34620666503906,\n              27.97499795326776\n            ],\n            [\n              -81.36886596679688,\n              27.97984914504167\n            ],\n            [\n              -81.36817932128906,\n              27.971359416256693\n            ],\n            [\n              -81.34963989257812,\n              27.934967298584915\n            ],\n            [\n              -81.31599426269531,\n              27.921013735392084\n            ],\n            [\n              -81.32148742675781,\n              27.90159708626247\n            ],\n            [\n              -81.31050109863281,\n              27.883390812774888\n            ],\n            [\n              -81.309814453125,\n              27.867609565973098\n            ],\n            [\n              -81.30775451660156,\n              27.859111019382624\n            ],\n            [\n              -81.24938964843749,\n              27.840897604499386\n            ],\n            [\n              -81.24114990234374,\n              27.8421119273228\n            ],\n            [\n              -81.2164306640625,\n              27.81782288866404\n            ],\n            [\n              -81.221923828125,\n              27.79352841586229\n            ],\n            [\n              -81.16561889648438,\n              27.685352198428955\n            ],\n            [\n              -81.17385864257812,\n              27.67379895781762\n            ],\n            [\n              -81.17935180664061,\n              27.581937684694736\n            ],\n            [\n              -81.22673034667969,\n              27.54480631775389\n            ],\n            [\n              -81.21780395507811,\n              27.492435852729894\n            ],\n            [\n              -81.18690490722655,\n              27.421147650741265\n            ],\n            [\n              -81.12648010253906,\n              27.38030375235113\n            ],\n            [\n              -81.05575561523438,\n              27.34554408168226\n            ],\n            [\n              -81.05026245117188,\n              27.31565424126349\n            ],\n            [\n              -81.02210998535156,\n              27.290027966206214\n            ],\n            [\n              -80.98297119140625,\n              27.21433494529935\n            ],\n            [\n              -80.96992492675781,\n              27.178301644674047\n            ],\n            [\n              -80.8978271484375,\n              27.15447663185513\n            ],\n            [\n              -81.02485656738281,\n              27.039556602163195\n            ],\n            [\n              -81.11686706542967,\n              26.974097380304208\n            ],\n            [\n              -81.09832763671875,\n              26.93492599433896\n            ],\n            [\n              -81.03103637695311,\n              26.866343323987433\n            ],\n            [\n              -80.97267150878906,\n              26.882268012500234\n            ],\n            [\n              -80.93971252441406,\n              26.759712731468568\n            ],\n            [\n              -80.82778930664062,\n              26.69163742147271\n            ],\n            [\n              -80.73165893554688,\n              26.676913083105454\n            ],\n            [\n              -80.67741394042969,\n              26.748063090366852\n            ],\n            [\n              -80.6890869140625,\n              26.800170623841804\n            ],\n            [\n              -80.64788818359375,\n              26.83203637945121\n            ],\n            [\n              -80.60531616210938,\n              26.895740996697807\n            ],\n            [\n              -80.60462951660156,\n              26.974097380304208\n            ],\n            [\n              -80.65132141113281,\n              27.088473156555896\n            ],\n            [\n              -80.65475463867188,\n              27.112923428713707\n            ],\n            [\n              -80.73234558105469,\n              27.18685297304107\n            ],\n            [\n              -80.7879638671875,\n              27.216777459372924\n            ],\n            [\n              -80.83946228027344,\n              27.202732272259045\n            ],\n            [\n              -80.96786499023438,\n              27.254629577800063\n            ],\n            [\n              -80.98640441894531,\n              27.37908429955532\n            ],\n            [\n              -81.06124877929688,\n              27.423585614918853\n            ],\n            [\n              -81.10176086425781,\n              27.53993569880378\n            ],\n            [\n              -81.09695434570312,\n              27.647039394312074\n            ],\n            [\n              -81.18690490722655,\n              27.800817328100297\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"112","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a03d3e4b0c8380cd50680","contributors":{"authors":[{"text":"Warne, A.G.","contributorId":97669,"corporation":false,"usgs":true,"family":"Warne","given":"A.G.","email":"","affiliations":[],"preferred":false,"id":392877,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Toth, L.A.","contributorId":55174,"corporation":false,"usgs":true,"family":"Toth","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":392876,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"White, W.A.","contributorId":24489,"corporation":false,"usgs":true,"family":"White","given":"W.A.","email":"","affiliations":[],"preferred":false,"id":392875,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022257,"text":"70022257 - 2000 - Empirical assessment of fish introductions in a subtropical wetland: An evaluation of contrasting views","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022257","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1018,"text":"Biological Invasions","active":true,"publicationSubtype":{"id":10}},"title":"Empirical assessment of fish introductions in a subtropical wetland: An evaluation of contrasting views","docAbstract":"We summarized data from eight quantitative fish surveys conducted in southern Florida to evaluate the distribution and relative abundance of introduced fishes across a variety of habitats. These surveys encompassed marsh and canal habitats throughout most of the Everglades region, including the mangrove fringe of Florida Bay. Two studies provided systematically collected density information over a 20-year period, and documented the first local appearance of four introduced fishes based on their repeated absence in prior surveys. Those species displayed a pattern of rapid population growth followed by decline, then persistence at lower densities. Estuarine areas in the southern Everglades, characterized by natural tidal creeks surrounded by mangrove-dominated marshes, and canals held the largest introduced-fish populations. Introduced fishes were also common, at times exceeding 50% of the fish community, in solution holes that serve as dry-season refuges in short-hydroperiod rockland habitats of the eastern Everglades. Wet prairies and alligator ponds distant from canals generally held few individuals of introduced fishes. These patterns suggest that the introduced fishes in southern Florida at present may not be well-adapted to persist in freshwater marshes of the Everglades, possibly because of an interaction of periodic cold-temperature stress and hydrologic fluctuation. Our analyses indicated low densities of these fishes in central or northern Everglades wet-prairie communities, and, in the absence of experimental data, little evidence of biotic effects in this spatially extensive habitat. There is no guarantee that this condition will be maintained, especially under the cumulative effects of future invasions or environmental change.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Biological Invasions","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/A:1011488118444","issn":"13873547","usgsCitation":"Trexler, J., Loftus, W., Jordan, F., Lorenz, J., Chick, J., and Kobza, R.M., 2000, Empirical assessment of fish introductions in a subtropical wetland: An evaluation of contrasting views: Biological Invasions, v. 2, no. 4, p. 265-277, https://doi.org/10.1023/A:1011488118444.","startPage":"265","endPage":"277","numberOfPages":"13","costCenters":[],"links":[{"id":206736,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1011488118444"},{"id":230669,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0904e4b0c8380cd51d74","contributors":{"authors":[{"text":"Trexler, J.C.","contributorId":23108,"corporation":false,"usgs":true,"family":"Trexler","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":392869,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Loftus, W.F.","contributorId":29363,"corporation":false,"usgs":true,"family":"Loftus","given":"W.F.","email":"","affiliations":[],"preferred":false,"id":392870,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Jordan, F.","contributorId":80622,"corporation":false,"usgs":true,"family":"Jordan","given":"F.","affiliations":[],"preferred":false,"id":392872,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Lorenz, J.J.","contributorId":67058,"corporation":false,"usgs":true,"family":"Lorenz","given":"J.J.","email":"","affiliations":[],"preferred":false,"id":392871,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Chick, J.H.","contributorId":93004,"corporation":false,"usgs":true,"family":"Chick","given":"J.H.","affiliations":[],"preferred":false,"id":392873,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Kobza, Robert M.","contributorId":103822,"corporation":false,"usgs":false,"family":"Kobza","given":"Robert","email":"","middleInitial":"M.","affiliations":[{"id":7036,"text":"South Florida Water Management District","active":true,"usgs":false}],"preferred":false,"id":392874,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70022677,"text":"70022677 - 2000 - Nutrient concentrations and yields in undeveloped stream basins of the United States","interactions":[],"lastModifiedDate":"2022-08-25T15:58:33.578223","indexId":"70022677","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Nutrient concentrations and yields in undeveloped stream basins of the United States","docAbstract":"Data from 85 sites across the United States were used to estimate concentrations and yields of selected nutrients in streams draining relatively undeveloped basins. Flow-weighted concentrations during 1990-1995 were generally low with median basin concentrations of 0.020, 0.087, 0.26, 0.010, and 0.022 milligrams per liter (mg/L) for ammonia as N, nitrate as N, total nitrogen, orthophosphate as P, and total phosphorus, respectively. The flow-weighted concentration of nitrate exceeded 0.6 mg/L in only three basins. Total nitrogen exceeded 1 mg/L in only four basins, and total phosphorus exceeded 0.1 mg/L in only four basins. The median annual basin yield of ammonia as N, nitrate as N, total nitrogen, orthophosphate as P, and total phosphorus was 8.1, 26, 86, 2.8, and 8.5 kilograms per square kilometer, respectively. Concentrations and yields of nitrate tended to be highest in northeastern and mid-Atlantic coastal states and correlated well with areas of high atmospheric nitrogen deposition. Concentrations and yields of total nitrogen were highest in the southeastern part of the nation and in parts of the upper Midwest. In the northeast, nitrate was generally the predominant form of nitrogen, and in the southeast and parts of the upper Midwest, organic nitrogen was the dominant form. Concentrations of total phosphorus were generally highest in the Rocky Mountain and Central Plain states.Data from 85 sites across the United States were used to estimate concentrations and yields of selected nutrients in streams draining relatively undeveloped basins. Flow-weighted concentrations during 1990-1995 were generally low with median basin concentrations of 0.020, 0.087, 0.26, 0.010, and 0.022 milligrams per liter (mg/L) for ammonia as N, nitrate as N, total nitrogen, orthophosphate as P, and total phosphorus, respectively. The flow-weighted concentration of nitrate exceeded 0.6 mg/L in only three basins, Total nitrogen exceeded 1 mg/L in only four basins, and total phosphorus exceeded 0.1 mg/L in only four basins. The median annual basin yield of ammonia as N, nitrate as N, total nitrogen, orthophosphate as P, and total phosphorus was 8.1, 26, 86, 2.8, and 8.5 kilograms per square kilometer, respectively. Concentrations and yields of nitrate tended to be highest in northeastern and mid-Atlantic coastal states and correlated well with areas of high atmospheric nitrogen deposition. Concentrations and yields of total nitrogen were highest in the southeastern part of the nation and in parts of the upper Midwest. In the northeast, nitrate was generally the predominant form of nitrogen, and in the southeast and parts of the upper Midwest, organic nitrogen was the dominant form. Concentrations of total phosphorus were generally highest in the Rocky Mountain and Central Plain states.Data collected across the US from 85 streams draining relatively undeveloped basins were used to identify broad regional and national patterns in nutrient concentrations and yields. The basins of interest were selected from three USGS programs: the Hydrologic Benchmark Network, the National Water-Quality Assessment, and the Research Program. Water samples from most basins were collected on a weekly to bimonthly schedule. While the flow-weighted concentrations of nutrients varied, concentrations were low in most basins. Median flow-weighted concentrations of ammonia, nitrate, total nitrogen, orthophosphate, and total phosphorus were 0.020, 0.087, 0.26, 0.010, and 0.022 mg/l, respectively. Nitrate concentrations tended to be highest in the northeastern US, while southeastern and north-central basins had some of the highest NH3 concentrations. Flow-weighted concentrations of total P were generally highest in the Rocky Mountain and Central Plain states and in parts of the southeast.","language":"English","publisher":"American Water Resources Association","publisherLocation":"Herndon, VA, United States","doi":"10.1111/j.1752-1688.2000.tb04311.x","issn":"1093474X","usgsCitation":"Clark, G.M., Mueller, D., and Mast, M., 2000, Nutrient concentrations and yields in undeveloped stream basins of the United States: Journal of the American Water Resources Association, v. 36, no. 4, p. 849-867, https://doi.org/10.1111/j.1752-1688.2000.tb04311.x.","productDescription":"19 p.","startPage":"849","endPage":"867","costCenters":[],"links":[{"id":479306,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.586.3279","text":"External Repository"},{"id":233884,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"MultiPolygon\",\"coordinates\":[[[[-66.28243,18.51476],[-65.7713,18.42668],[-65.591,18.22803],[-65.84716,17.97591],[-66.59993,17.98182],[-67.18416,17.94655],[-67.24243,18.37446],[-67.10068,18.5206],[-66.28243,18.51476]]],[[[-155.54211,19.08348],[-155.68817,18.91619],[-155.93665,19.05939],[-155.90806,19.33888],[-156.07347,19.70294],[-156.02368,19.81422],[-155.85008,19.97729],[-155.91907,20.17395],[-155.86108,20.26721],[-155.78505,20.2487],[-155.40214,20.07975],[-155.22452,19.99302],[-155.06226,19.8591],[-154.80741,19.50871],[-154.83147,19.45328],[-155.22217,19.23972],[-155.54211,19.08348]]],[[[-156.07926,20.64397],[-156.41445,20.57241],[-156.58673,20.783],[-156.70167,20.8643],[-156.71055,20.92676],[-156.61258,21.01249],[-156.25711,20.91745],[-155.99566,20.76404],[-156.07926,20.64397]]],[[[-156.75824,21.17684],[-156.78933,21.06873],[-157.32521,21.09777],[-157.25027,21.21958],[-156.75824,21.17684]]],[[[-157.65283,21.32217],[-157.70703,21.26442],[-157.7786,21.27729],[-158.12667,21.31244],[-158.2538,21.53919],[-158.29265,21.57912],[-158.0252,21.71696],[-157.94161,21.65272],[-157.65283,21.32217]]],[[[-159.34512,21.982],[-159.46372,21.88299],[-159.80051,22.06533],[-159.74877,22.1382],[-159.5962,22.23618],[-159.36569,22.21494],[-159.34512,21.982]]],[[[-94.81758,49.38905],[-94.64,48.84],[-94.32914,48.67074],[-93.63087,48.60926],[-92.61,48.45],[-91.64,48.14],[-90.83,48.27],[-89.6,48.01],[-89.27292,48.01981],[-88.37811,48.30292],[-87.43979,47.94],[-86.46199,47.55334],[-85.65236,47.22022],[-84.87608,46.90008],[-84.77924,46.6371],[-84.54375,46.53868],[-84.6049,46.4396],[-84.3367,46.40877],[-84.14212,46.51223],[-84.09185,46.27542],[-83.89077,46.11693],[-83.61613,46.11693],[-83.46955,45.99469],[-83.59285,45.81689],[-82.55092,45.34752],[-82.33776,44.44],[-82.13764,43.57109],[-82.43,42.98],[-82.9,42.43],[-83.12,42.08],[-83.142,41.97568],[-83.02981,41.8328],[-82.69009,41.67511],[-82.43928,41.67511],[-81.27775,42.20903],[-80.24745,42.3662],[-78.93936,42.86361],[-78.92,42.965],[-79.01,43.27],[-79.17167,43.46634],[-78.72028,43.62509],[-77.73789,43.62906],[-76.82003,43.62878],[-76.5,44.01846],[-76.375,44.09631],[-75.31821,44.81645],[-74.867,45.00048],[-73.34783,45.00738],[-71.50506,45.0082],[-71.405,45.255],[-71.08482,45.30524],[-70.66,45.46],[-70.305,45.915],[-69.99997,46.69307],[-69.23722,47.44778],[-68.905,47.185],[-68.23444,47.35486],[-67.79046,47.06636],[-67.79134,45.70281],[-67.13741,45.13753],[-66.96466,44.8097],[-68.03252,44.3252],[-69.06,43.98],[-70.11617,43.68405],[-70.64548,43.09024],[-70.81489,42.8653],[-70.825,42.335],[-70.495,41.805],[-70.08,41.78],[-70.185,42.145],[-69.88497,41.92283],[-69.96503,41.63717],[-70.64,41.475],[-71.12039,41.49445],[-71.86,41.32],[-72.295,41.27],[-72.87643,41.22065],[-73.71,40.9311],[-72.24126,41.11948],[-71.945,40.93],[-73.345,40.63],[-73.982,40.628],[-73.95232,40.75075],[-74.25671,40.47351],[-73.96244,40.42763],[-74.17838,39.70926],[-74.90604,38.93954],[-74.98041,39.1964],[-75.20002,39.24845],[-75.52805,39.4985],[-75.32,38.96],[-75.07183,38.78203],[-75.05673,38.40412],[-75.37747,38.01551],[-75.94023,37.21689],[-76.03127,37.2566],[-75.72205,37.93705],[-76.23287,38.31921],[-76.35,39.15],[-76.54272,38.71762],[-76.32933,38.08326],[-76.99,38.23999],[-76.30162,37.91794],[-76.25874,36.9664],[-75.9718,36.89726],[-75.86804,36.55125],[-75.72749,35.55074],[-76.36318,34.80854],[-77.39763,34.51201],[-78.05496,33.92547],[-78.55435,33.86133],[-79.06067,33.49395],[-79.20357,33.15839],[-80.30132,32.50935],[-80.86498,32.0333],[-81.33629,31.44049],[-81.49042,30.72999],[-81.31371,30.03552],[-80.98,29.18],[-80.53558,28.47213],[-80.53,28.04],[-80.05654,26.88],[-80.08801,26.20576],[-80.13156,25.81677],[-80.38103,25.20616],[-80.68,25.08],[-81.17213,25.20126],[-81.33,25.64],[-81.71,25.87],[-82.24,26.73],[-82.70515,27.49504],[-82.85526,27.88624],[-82.65,28.55],[-82.93,29.1],[-83.70959,29.93656],[-84.1,30.09],[-85.10882,29.63615],[-85.28784,29.68612],[-85.7731,30.15261],[-86.4,30.4],[-87.53036,30.27433],[-88.41782,30.3849],[-89.18049,30.31598],[-89.59383,30.15999],[-89.41373,29.89419],[-89.43,29.48864],[-89.21767,29.29108],[-89.40823,29.15961],[-89.77928,29.30714],[-90.15463,29.11743],[-90.88022,29.14854],[-91.62678,29.677],[-92.49906,29.5523],[-93.22637,29.78375],[-93.84842,29.71363],[-94.69,29.48],[-95.60026,28.73863],[-96.59404,28.30748],[-97.14,27.83],[-97.37,27.38],[-97.38,26.69],[-97.33,26.21],[-97.14,25.87],[-97.53,25.84],[-98.24,26.06],[-99.02,26.37],[-99.3,26.84],[-99.52,27.54],[-100.11,28.11],[-100.45584,28.69612],[-100.9576,29.38071],[-101.6624,29.7793],[-102.48,29.76],[-103.11,28.97],[-103.94,29.27],[-104.45697,29.57196],[-104.70575,30.12173],[-105.03737,30.64402],[-105.63159,31.08383],[-106.1429,31.39995],[-106.50759,31.75452],[-108.24,31.75485],[-108.24194,31.34222],[-109.035,31.34194],[-111.02361,31.33472],[-113.30498,32.03914],[-114.815,32.52528],[-114.72139,32.72083],[-115.99135,32.61239],[-117.12776,32.53534],[-117.29594,33.04622],[-117.944,33.62124],[-118.4106,33.74091],[-118.51989,34.02778],[-119.081,34.078],[-119.43884,34.34848],[-120.36778,34.44711],[-120.62286,34.60855],[-120.74433,35.15686],[-121.71457,36.16153],[-122.54747,37.55176],[-122.51201,37.78339],[-122.95319,38.11371],[-123.7272,38.95166],[-123.86517,39.76699],[-124.39807,40.3132],[-124.17886,41.14202],[-124.2137,41.99964],[-124.53284,42.76599],[-124.14214,43.70838],[-124.02053,44.6159],[-123.89893,45.52341],[-124.07963,46.86475],[-124.39567,47.72017],[-124.68721,48.18443],[-124.5661,48.37971],[-123.12,48.04],[-122.58736,47.096],[-122.34,47.36],[-122.5,48.18],[-122.84,49],[-120,49],[-117.03121,49],[-116.04818,49],[-113,49],[-110.05,49],[-107.05,49],[-104.04826,48.99986],[-100.65,49],[-97.22872,49.0007],[-95.15907,49],[-95.15609,49.38425],[-94.81758,49.38905]]],[[[-153.00631,57.11584],[-154.00509,56.73468],[-154.5164,56.99275],[-154.67099,57.4612],[-153.76278,57.81657],[-153.22873,57.96897],[-152.56479,57.90143],[-152.14115,57.59106],[-153.00631,57.11584]]],[[[-165.57916,59.90999],[-166.19277,59.75444],[-166.84834,59.94141],[-167.45528,60.21307],[-166.46779,60.38417],[-165.67443,60.29361],[-165.57916,59.90999]]],[[[-171.73166,63.78252],[-171.11443,63.59219],[-170.49111,63.69498],[-169.68251,63.43112],[-168.68944,63.29751],[-168.77194,63.1886],[-169.52944,62.97693],[-170.29056,63.19444],[-170.67139,63.37582],[-171.55306,63.31779],[-171.79111,63.40585],[-171.73166,63.78252]]],[[[-155.06779,71.14778],[-154.34417,70.69641],[-153.90001,70.88999],[-152.21001,70.82999],[-152.27,70.60001],[-150.73999,70.43002],[-149.72,70.53001],[-147.61336,70.21403],[-145.68999,70.12001],[-144.92001,69.98999],[-143.58945,70.15251],[-142.07251,69.85194],[-140.98599,69.712],[-140.9925,66.00003],[-140.99777,60.3064],[-140.013,60.27684],[-139.039,60.00001],[-138.34089,59.56211],[-137.4525,58.905],[-136.47972,59.46389],[-135.47583,59.78778],[-134.945,59.27056],[-134.27111,58.86111],[-133.35555,58.41029],[-132.73042,57.69289],[-131.70781,56.55212],[-130.00778,55.91583],[-129.97999,55.285],[-130.53611,54.80275],[-131.08582,55.17891],[-131.96721,55.49778],[-132.25001,56.37],[-133.53918,57.17889],[-134.07806,58.12307],[-135.03821,58.18771],[-136.62806,58.21221],[-137.80001,58.5],[-139.86779,59.53776],[-140.82527,59.72752],[-142.57444,60.08445],[-143.95888,59.99918],[-145.92556,60.45861],[-147.11437,60.88466],[-148.22431,60.67299],[-148.01807,59.97833],[-148.57082,59.91417],[-149.72786,59.70566],[-150.60824,59.36821],[-151.71639,59.15582],[-151.85943,59.74498],[-151.40972,60.7258],[-150.34694,61.03359],[-150.62111,61.28442],[-151.89584,60.7272],[-152.57833,60.06166],[-154.01917,59.35028],[-153.28751,58.86473],[-154.23249,58.14637],[-155.30749,57.72779],[-156.30833,57.42277],[-156.5561,56.97998],[-158.11722,56.46361],[-158.43332,55.99415],[-159.60333,55.56669],[-160.28972,55.64358],[-161.22305,55.36473],[-162.23777,55.02419],[-163.06945,54.68974],[-164.78557,54.40417],[-164.94223,54.57222],[-163.84834,55.03943],[-162.87,55.34804],[-161.80417,55.89499],[-160.5636,56.00805],[-160.07056,56.41806],[-158.68444,57.01668],[-158.4611,57.21692],[-157.72277,57.57],[-157.55027,58.32833],[-157.04167,58.91888],[-158.19473,58.6158],[-158.51722,58.78778],[-159.05861,58.42419],[-159.71167,58.93139],[-159.98129,58.57255],[-160.35527,59.07112],[-161.355,58.67084],[-161.96889,58.67166],[-162.05499,59.26693],[-161.87417,59.63362],[-162.51806,59.98972],[-163.81834,59.79806],[-164.66222,60.26748],[-165.34639,60.5075],[-165.35083,61.0739],[-166.12138,61.50002],[-165.73445,62.075],[-164.91918,62.63308],[-164.56251,63.14638],[-163.75333,63.21945],[-163.06722,63.05946],[-162.26056,63.54194],[-161.53445,63.45582],[-160.77251,63.76611],[-160.95834,64.2228],[-161.51807,64.40279],[-160.77778,64.7886],[-161.39193,64.77724],[-162.45305,64.55944],[-162.75779,64.33861],[-163.54639,64.55916],[-164.96083,64.44695],[-166.42529,64.68667],[-166.845,65.0889],[-168.11056,65.67],[-166.70527,66.08832],[-164.47471,66.57666],[-163.65251,66.57666],[-163.7886,66.07721],[-161.67777,66.11612],[-162.48971,66.73557],[-163.71972,67.11639],[-164.43099,67.61634],[-165.39029,68.04277],[-166.76444,68.35888],[-166.20471,68.88303],[-164.43081,68.91554],[-163.16861,69.37111],[-162.93057,69.85806],[-161.9089,70.33333],[-160.9348,70.44769],[-159.03918,70.89164],[-158.11972,70.82472],[-156.58082,71.35776],[-155.06779,71.14778]]]]},\"properties\":{\"name\":\"United States\"}}]}","volume":"36","issue":"4","noUsgsAuthors":false,"publicationDate":"2007-06-08","publicationStatus":"PW","scienceBaseUri":"505a697de4b0c8380cd73d52","contributors":{"authors":[{"text":"Clark, G. M.","contributorId":90325,"corporation":false,"usgs":true,"family":"Clark","given":"G.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":394509,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mueller, D. K.","contributorId":93525,"corporation":false,"usgs":true,"family":"Mueller","given":"D. K.","affiliations":[],"preferred":false,"id":394510,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mast, M.A.","contributorId":67871,"corporation":false,"usgs":true,"family":"Mast","given":"M.A.","affiliations":[],"preferred":false,"id":394508,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022716,"text":"70022716 - 2000 - Pesticides in the atmosphere of the Mississippi River Valley, part I: Rain","interactions":[],"lastModifiedDate":"2021-05-28T16:37:57.793953","indexId":"70022716","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":5331,"text":"Science of Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Pesticides in the atmosphere of the Mississippi River Valley, part I: Rain","docAbstract":"<div id=\"abstracts\" class=\"Abstracts\"><div id=\"aep-abstract-id8\" class=\"abstract author\"><div id=\"aep-abstract-sec-id9\"><p><span>Weekly composite rainfall samples were collected in three paired urban and agricultural regions of the Midwestern&nbsp;United States&nbsp;and along the Mississippi River during April–September 1995. The paired sampling sites were located in Mississippi, Iowa, and Minnesota. A background site, removed from dense urban and agriculture areas, was located near Lake Superior in Michigan.&nbsp;Herbicides&nbsp;were the predominant type of pesticide detected at every site. Each sample was analyzed for 47 compounds and 23 of 26 herbicides, 13 of 18&nbsp;insecticides, and three of three related transformation products were detected in one or more sample from each paired site. The detection frequency of herbicides and insecticides were nearly equivalent at the paired Iowa and Minnesota sites. In Mississippi, herbicides were detected more frequently at the agricultural site and insecticides were detected more frequently at the&nbsp;urban site. The highest total wet depositional amounts (μg pesticide/m</span><sup>2</sup>per season) occurred at the agricultural sites in Mississippi (1980 μg/m<sup>2</sup>) and Iowa (490 μg/m<sup>2</sup>) and at the urban site in Iowa (696 μg/m<sup>2</sup>). Herbicides accounted for the majority of the wet depositional loading at the Iowa and Minnesota sites, but methyl parathion (1740 μg/m<sup>2</sup><span>) was the dominant compound contributing to the total loading at the agricultural site in Mississippi.&nbsp;Atrazine, CIAT (a transformation product of atrazine and propazine) and dacthal were detected most frequently (76, 53, and 53%, respectively) at the background site indicating their propensity for long-range&nbsp;atmospheric transport.</span></p></div></div></div>","language":"English","publisher":"Elsevier","doi":"10.1016/S0048-9697(99)00543-4","usgsCitation":"Majewski, M., Foreman, W., and Goolsby, D.A., 2000, Pesticides in the atmosphere of the Mississippi River Valley, part I: Rain: Science of Total Environment, v. 248, no. 2-3, p. 201-212, https://doi.org/10.1016/S0048-9697(99)00543-4.","productDescription":"12 p.","startPage":"201","endPage":"212","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":452,"text":"National Water Quality Laboratory","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233854,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Mississippi River Valley","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -88.76953125,\n              30.334953881988564\n            ],\n            [\n              -88.154296875,\n              35.02999636902566\n            ],\n            [\n              -83.6279296875,\n              35.35321610123823\n            ],\n            [\n              -81.650390625,\n              36.27970720524017\n            ],\n            [\n              -83.84765625,\n              36.59788913307022\n            ],\n            [\n              -82.001953125,\n              37.50972584293751\n            ],\n            [\n              -82.9248046875,\n              38.47939467327645\n            ],\n            [\n              -80.6396484375,\n              39.740986355883564\n            ],\n            [\n              -80.6396484375,\n              41.96765920367816\n            ],\n            [\n              -83.3642578125,\n              41.705728515237524\n            ],\n            [\n              -82.5732421875,\n              43.16512263158296\n            ],\n            [\n              -83.0126953125,\n              44.05601169578525\n            ],\n            [\n              -83.5400390625,\n              45.24395342262324\n            ],\n            [\n              -83.8916015625,\n              46.40756396630067\n            ],\n            [\n              -85.1220703125,\n              46.89023157359399\n            ],\n            [\n              -88.2861328125,\n              47.45780853075031\n            ],\n            [\n              -89.912109375,\n              48.07807894349862\n            ],\n            [\n              -95.5810546875,\n              48.922499263758255\n            ],\n            [\n              -96.8994140625,\n              49.03786794532644\n            ],\n            [\n              -96.591796875,\n              43.61221676817573\n            ],\n            [\n              -95.7568359375,\n              40.78054143186033\n            ],\n            [\n              -94.658203125,\n              38.92522904714054\n            ],\n            [\n              -94.52636718749999,\n              35.88905007936091\n            ],\n            [\n              -94.482421875,\n              33.46810795527896\n            ],\n            [\n              -93.955078125,\n              33.358061612778876\n            ],\n            [\n              -94.04296874999999,\n              31.98944183792288\n            ],\n            [\n              -93.55957031249999,\n              30.789036751261136\n            ],\n            [\n              -93.6474609375,\n              29.80251790576445\n            ],\n            [\n              -90.3076171875,\n              29.075375179558346\n            ],\n            [\n              -88.76953125,\n              30.334953881988564\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"248","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a776ce4b0c8380cd784bb","contributors":{"authors":[{"text":"Majewski, M.S.","contributorId":88501,"corporation":false,"usgs":true,"family":"Majewski","given":"M.S.","email":"","affiliations":[],"preferred":false,"id":394644,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Foreman, W.T.","contributorId":94684,"corporation":false,"usgs":true,"family":"Foreman","given":"W.T.","email":"","affiliations":[],"preferred":false,"id":394645,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Goolsby, D. A.","contributorId":50508,"corporation":false,"usgs":true,"family":"Goolsby","given":"D.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":394643,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022230,"text":"70022230 - 2000 - Modeling regional salinization of the Ogallala aquifer, Southern High Plains, TX, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022230","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Modeling regional salinization of the Ogallala aquifer, Southern High Plains, TX, USA","docAbstract":"Two extensive plumes (combined area > 1000 km2) have been delineated within the Ogallala aquifer in the Southern High Plains, TX, USA. Salinity varies within the plumes spatially and increases with depth; Cl ranges from 50 to >500 mg 1-1. Variable-density flow modeling using SUTRA has identified three broad regions of upward cross-formational flow from the underlying evaporite units. The upward discharge within the modeled plume area is in the range of 10-4-10-5 m3 day-1, and the TDS concentrations are typically >3000 mg 1-1. Regions of increased salinity, identified within the Whitehorse Group (evaporite unit) underlying the Ogallala aquifer, are controlled by the structure and thickness variations relative to the recharge areas. Distinct flow paths, on the order of tens of km to >100 km in length, and varying flow velocities indicate that the salinization of the Ogallala aquifer has been a slow, ongoing process and may represent circulation of waters recharged during Pleistocene or earlier times. On-going pumping has had negligible impact on the salinity distribution in the Ogallala aquifer, although simulations indicate that the velocity distribution in the underlying units may have been affected to depths of 150 m after 30 years of pumping. Because the distribution of saline ground water in this region of the Ogallala aquifer is heterogeneous, careful areal and vertical characterization is warranted prior to any well-field development. (C) 2000 Elsevier Science B.V.Two extensive plumes (combined area >1000 km2) have been delineated within the Ogallala aquifer in the Southern High Plains, TX, USA. Salinity varies within the plumes spatially and increases with depth; Cl ranges from 50 to >500 mg l-1. Variable-density flow modeling using SUTRA has identified three broad regions of upward cross-formational flow from the underlying evaporite units. The upward discharge within the modeled plume area is in the range of 10-4-10-5 m3 day-1, and the TDS concentrations are typically >3000 mg l-1. Regions of increased salinity, identified within the Whitehorse Group (evaporite unit) underlying the Ogallala aquifer, are controlled by the structure and thickness variations relative to the recharge areas. Distinct flow paths, on the order of tens of km to >100 km in length, and varying flow velocities indicate that the salinization of the Ogallala aquifer has been a slow, ongoing process and may represent circulation of waters recharged during Pleistocene or earlier times. On-going pumping has had negligible impact on the salinity distribution in the Ogallala aquifer, although simulations indicate that the velocity distribution in the underlying units may have been affected to depths of 150 m after 30 years of pumping. Because the distribution of saline ground water in this region of the Ogallala aquifer is heterogeneous, careful areal and vertical characterization is warranted prior to any well-field development.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Science B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0022-1694(00)00314-0","issn":"00221694","usgsCitation":"Mehta, S., Fryar, A., Brady, R., and Morin, R.H., 2000, Modeling regional salinization of the Ogallala aquifer, Southern High Plains, TX, USA: Journal of Hydrology, v. 238, no. 1-2, p. 44-64, https://doi.org/10.1016/S0022-1694(00)00314-0.","startPage":"44","endPage":"64","numberOfPages":"21","costCenters":[],"links":[{"id":206802,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(00)00314-0"},{"id":230822,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"238","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5c22e4b0c8380cd6fa71","contributors":{"authors":[{"text":"Mehta, S.","contributorId":74902,"corporation":false,"usgs":true,"family":"Mehta","given":"S.","email":"","affiliations":[],"preferred":false,"id":392778,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fryar, A.E.","contributorId":59928,"corporation":false,"usgs":true,"family":"Fryar","given":"A.E.","affiliations":[],"preferred":false,"id":392776,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Brady, R.M.","contributorId":70558,"corporation":false,"usgs":true,"family":"Brady","given":"R.M.","email":"","affiliations":[],"preferred":false,"id":392777,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Morin, R. H.","contributorId":31794,"corporation":false,"usgs":true,"family":"Morin","given":"R.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":392775,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022202,"text":"70022202 - 2000 - Differences in topographic characteristics computed from 100- and 1000-m resolution digital elevation model data","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022202","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"Differences in topographic characteristics computed from 100- and 1000-m resolution digital elevation model data","docAbstract":"Topographic characteristics computed from 100- and 1000-m resolution digital elevation model (DEM) data are compared for 50 locations representing varied terrain in the conterminous USA. The topographic characteristics are three parameters used extensively in hydrological research and modelling - slope (S), specific catchment area (A(s)) and a wetness index computed as the logarithm of the specific catchment area divided by slope [ln(A(s)/S)]. Slope values computed from 1000-m DEMs are smaller than those computed from 100-m DEMs; specific catchment area and the wetness index are larger for the 1000-m DEMs compared with the 100-m DEMs. Most of the differences between the 100- and 1000-m resolution DEMs can be attributed to terrain-discretization effects in the computation of the topographic characteristics and are not the result of smoothing or loss of terrain detail in the coarse data. In general, the terrain-discretization effects are greatest on flat terrain with long length-scale features, and the smoothing effects are greatest on steep terrain with short length-scale features. For the most part, the differences in the average values of the topographic characteristics computed from 100- and 1000-m resolution DEMs are predictable; that is, biases in the mean values for the characteristics computed from a 1000-m DEM can be corrected with simple linear equations. Copyright (C) 2000 John Wiley and Sons, Ltd.Topographic characteristics computed from 100- and 1000-m resolution digital elevation model (DEM) data are compared for 50 locations representing varied terrain in the conterminous USA. The topographic characteristics are three parameters used extensively in hydrological research and modelling - slope (S), specific catchment area (As) and a wetness index computed as the logarithm of the specific catchment area divided by slope [In(As/S)]. Slope values computed from 1000-m DEMs are smaller than those computed from 100-m DEMs; specific catchment area and the wetness index are larger for the 1000-m DEMs compared with the 100-m DEMs. Most of the differences between the 100- and 1000-m resolution DEMs can be attributed to terrain-discretization effects in the computation of the topographic characteristics and are not the result of smoothing or loss of terrain detail in the coarse data. In general, the terrain-discretization effects are greatest on flat terrain with long length-scale features, and the smoothing effects are greatest on steep terrain with short length-scale features. For the most part, the differences in the average values of the topographic characteristics computed from 100- and 1000-m resolution DEMs are predictable; that is, biases in the mean values for the characteristics computed from a 1000-m DEM can be corrected with simple linear equations.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrological Processes","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"John Wiley & Sons Ltd","publisherLocation":"Chichester, United Kingdom","doi":"10.1002/(SICI)1099-1085(20000430)14:6<987::AID-HYP980>3.0.CO;2-A","issn":"08856087","usgsCitation":"Wolock, D., and McCabe, G., 2000, Differences in topographic characteristics computed from 100- and 1000-m resolution digital elevation model data: Hydrological Processes, v. 14, no. 6, p. 987-1002, https://doi.org/10.1002/(SICI)1099-1085(20000430)14:6<987::AID-HYP980>3.0.CO;2-A.","startPage":"987","endPage":"1002","numberOfPages":"16","costCenters":[],"links":[{"id":479339,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1002/(sici)1099-1085(20000430)14:6<987::aid-hyp980>3.0.co;2-a","text":"Publisher Index Page"},{"id":206642,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/(SICI)1099-1085(20000430)14:6<987::AID-HYP980>3.0.CO;2-A"},{"id":230446,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"14","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a00f2e4b0c8380cd4f9e2","contributors":{"authors":[{"text":"Wolock, D.M. 0000-0002-6209-938X","orcid":"https://orcid.org/0000-0002-6209-938X","contributorId":36601,"corporation":false,"usgs":true,"family":"Wolock","given":"D.M.","affiliations":[],"preferred":false,"id":392694,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McCabe, G.J. 0000-0002-9258-2997","orcid":"https://orcid.org/0000-0002-9258-2997","contributorId":12961,"corporation":false,"usgs":true,"family":"McCabe","given":"G.J.","affiliations":[],"preferred":false,"id":392693,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022192,"text":"70022192 - 2000 - Stable isotope systematics of sulfate minerals","interactions":[],"lastModifiedDate":"2020-09-25T19:03:02.20853","indexId":"70022192","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3281,"text":"Reviews in Mineralogy and Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Stable isotope systematics of sulfate minerals","docAbstract":"<p>Stable isotope studies of sulfate minerals are especially useful for unraveling the geochemical history of geological systems. All sulfate minerals can yield sulfur and oxygen isotope data. Hydrous sulfate minerals, such as gypsum, also yield oxygen and hydrogen isotope data for the water of hydration, and more complex sulfate minerals, such as alunite and jarosite also yield oxygen and hydrogen isotope data from hydroxyl sites. Applications of stable isotope data can be divided into two broad categories: geothermometry and tracer studies. The equilibrium partitioning of stable isotopes between two substances, such as the isotopes of sulfur between barite and pyrite, is a function of temperature. Studies can also use stable isotopes as a tracer to fingerprint various sources of hydrogen, oxygen, and sulfur, and to identify physical and chemical processes such as evaporation of water, mixing of waters, and reduction of sulfate to sulfide.</p><p>Studies of sulfate minerals range from low-temperature surficial processes associated with the evaporation of seawater to form evaporite deposits to high-temperature magmatic-hydrothermal processes associated with the formation of base-and precious-metal deposits. Studies have been conducted on scales from submicroscopic chemical processes associated with the weathering of pyrite to global processes affecting the sulfur budget of the oceans. Sulfate isotope studies provide important information to investigations of energy and mineral resources, environmental geochemistry, paleoclimates, oceanography (past and present), sedimentary, igneous, and metamorphic processes, Earth systems, geomicrobiology, and hydrology.</p><p>One of the most important aspects of understanding and interpreting the stable isotope characteristics of sulfate minerals is the complex interplay between equilibrium and kinetic chemical and isotopic processes. With few exceptions, sulfate minerals are precipitated from water or have extensively interacted with water at some time in their history. Because of this nearly ubiquitous association with water, the kinetics of isotopic exchange reactions among dissolved species and solids are fundamental in dictating the isotopic composition of sulfate minerals. In general, the heavier isotope of sulfur is enriched in the higher oxidation state, such that under equilibrium conditions, sulfate minerals (e.g. barite, anhydrite) are expected to be enriched in the heavy isotope relative to disulfide minerals (e.g. pyrite, marcasite), which in turn are expected to be enriched relative to monosulfide minerals (e.g. pyrrhotite, sphalerite, galena) (<a class=\"link link-ref link-reveal xref-bibr\" data-open=\"sakai-1968\">Sakai 1968</a>,<span>&nbsp;</span><a class=\"link link-ref link-reveal xref-bibr\" data-open=\"bachinski-1969\">Bachinski 1969</a>). The kinetics of isotopic exchange among minerals with sulfur at the same oxidation state, such as sphalerite, and galena, are such that equilibrium is commonly observed. In contrast, isotopic equilibrium for exchange reactions between minerals of different oxidation states depends on factors such as the pH, time and temperature of reaction, the direction of reaction, fluid composition, and the presence or absence of catalysts (<a class=\"link link-ref link-reveal xref-bibr\" data-open=\"ohmoto-and-lasaga-1982\">Ohmoto and Lasaga 1982</a>). The kinetics of oxygen isotope exchange between dissolved sulfate and water are extremely sluggish. Extrapolation of the high-temperature (100 to 300°C) isotopic exchange kinetic data of<span>&nbsp;</span><a class=\"link link-ref link-reveal xref-bibr\" data-open=\"chiba-and-sakai-1985\">Chiba and Sakai (1985)</a><span>&nbsp;</span>to ambient temperatures suggests that it would take several billions of years for dissolved sulfate and seawater to reach oxygen isotopic equilibrium. In contrast, the residence time of sulfate in the oceans is only 7.9 million years (<a class=\"link link-ref link-reveal xref-bibr\" data-open=\"holland-1978\">Holland 1978</a>). However, at higher temperatures (&gt;200°C), oxygen isotopic exchange is sufficiently rapid to permit application of sulfate isotope geothermometry to geothermal systems and hydrothermal mineral deposits. In general, equilibrium prevails at low pH and high temperatures, whereas kinetic factors preclude equilibrium at low temperatures even at low pH. Thus, the sluggish kinetics of sulfur and oxygen isotope exchange reaction at low temperatures impair the use of these isotopes to understand the conditions of formation of sulfate minerals in these environments. However, because of these slow kinetics, the oxygen and sulfur isotopic compositions of sulfate minerals may preserve a record of the sources and processes that initially produced the dissolved sulfate, because the isotope ratios may not re-equilibrate during fluid transport and mineral precipitation.</p><p>The first part of this chapter is designed to provide the reader with a basic understanding of the principles that form the foundations of stable isotope geochemistry. Next, an overview of analytical methods used to determine the stable isotope composition of sulfate minerals is presented. This overview is followed by a discussion of geochemical processes that determine the stable isotope characteristics of sulfate minerals and related compounds. The chapter then concludes with an examination of the stable isotope systematics of sulfate minerals in a variety of geochemical environments.</p>","language":"English","publisher":"Mineralogical Society of America","doi":"10.2138/rmg.2000.40.12","issn":"15296466","usgsCitation":"Seal, R., Alpers, C.N., and Rye, R.O., 2000, Stable isotope systematics of sulfate minerals: Reviews in Mineralogy and Geochemistry, v. 40, no. 1, p. 541-602, https://doi.org/10.2138/rmg.2000.40.12.","productDescription":"62 p.","startPage":"541","endPage":"602","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230289,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"40","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b967fe4b08c986b31b54d","contributors":{"authors":[{"text":"Seal, Robert R.  II 0000-0003-0901-2529 rseal@usgs.gov","orcid":"https://orcid.org/0000-0003-0901-2529","contributorId":149066,"corporation":false,"usgs":true,"family":"Seal","given":"Robert R. ","suffix":"II","email":"rseal@usgs.gov","affiliations":[{"id":245,"text":"Eastern Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":false,"id":392667,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Alpers, Charles N. 0000-0001-6945-7365 cnalpers@usgs.gov","orcid":"https://orcid.org/0000-0001-6945-7365","contributorId":411,"corporation":false,"usgs":true,"family":"Alpers","given":"Charles","email":"cnalpers@usgs.gov","middleInitial":"N.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":392668,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rye, Robert O. rrye@usgs.gov","contributorId":1486,"corporation":false,"usgs":true,"family":"Rye","given":"Robert","email":"rrye@usgs.gov","middleInitial":"O.","affiliations":[{"id":211,"text":"Crustal Geophysics and Geochemistry Science Center","active":true,"usgs":true}],"preferred":true,"id":392666,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022174,"text":"70022174 - 2000 - Landscape-based spatially explicit species index models for everglades restoration","interactions":[],"lastModifiedDate":"2022-10-04T21:13:20.824443","indexId":"70022174","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1450,"text":"Ecological Applications","active":true,"publicationSubtype":{"id":10}},"title":"Landscape-based spatially explicit species index models for everglades restoration","docAbstract":"<p><span>As part of the effort to restore the ∼10 000-km</span><sup>2</sup><span>&nbsp;Everglades drainage in southern Florida, USA, we developed spatially explicit species index (SESI) models of a number of species and species groups. In this paper we describe the methodology and results of three such models: those for the Cape Sable Seaside Sparrow and the Snail Kite, and the species group model of long-legged wading birds. SESI models are designed to produce relative comparisons of one management alternative to a base scenario or to another alternative. The model outputs do not provide an exact quantitative prediction of future biotic group responses, but rather, when applying the same input data and different hydrologic plans, the models provide the best available means to compare the relative response of the biotic groups. We compared four alternative hydrologic management scenarios to a base scenario (i.e., predicted conditions assuming that current water management practices continue). We ranked the results of the comparisons for each set of models. No one scenario was beneficial to all species; however, they provide a uniform assessment, based on the best available observational information, of relative species responses to alternative water-management plans. As such, these models were used extensively in the restoration planning.</span></p>","language":"English","publisher":"Ecological Society of America","doi":"10.1890/1051-0761(2000)010[1849:LBSESI]2.0.CO;2","issn":"10510761","usgsCitation":"Curnutt, J.L., Comiskey, J., Nott, M., and Gross, L., 2000, Landscape-based spatially explicit species index models for everglades restoration: Ecological Applications, v. 10, no. 6, p. 1849-1860, https://doi.org/10.1890/1051-0761(2000)010[1849:LBSESI]2.0.CO;2.","productDescription":"12 p.","startPage":"1849","endPage":"1860","costCenters":[],"links":[{"id":230666,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Big Cypress National Preserve, Everglades National Park","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -81.38534545898438,\n              26.257704515406648\n            ],\n            [\n              -81.38259887695312,\n              26.236765673594668\n            ],\n            [\n              -81.43341064453125,\n              26.237997474610452\n            ],\n            [\n              -81.43203735351562,\n              26.2145910237943\n            ],\n            [\n              -81.55288696289062,\n              26.204734267107604\n            ],\n            [\n              -81.61056518554688,\n              26.199805575765804\n            ],\n            [\n              -81.72317504882812,\n              26.168996529230178\n            ],\n            [\n              -81.72317504882812,\n              25.888878582127084\n            ],\n            [\n              -81.67373657226562,\n              25.830797170738858\n            ],\n            [\n              -81.64764404296875,\n              25.88393659458397\n            ],\n            [\n              -81.48422241210938,\n              25.80112757645447\n            ],\n            [\n              -81.3702392578125,\n              25.697225529877763\n            ],\n            [\n              -81.27273559570311,\n              25.62914524992192\n            ],\n            [\n              -81.221923828125,\n              25.507742380531404\n            ],\n            [\n              -81.15600585937499,\n              25.37256835379414\n            ],\n            [\n              -81.18621826171875,\n              25.224820176765036\n            ],\n            [\n              -81.15188598632812,\n              25.152743274854956\n            ],\n            [\n              -81.09695434570312,\n              25.10798445491342\n            ],\n            [\n              -80.71792602539062,\n              25.111714982906328\n            ],\n            [\n              -80.48721313476562,\n              25.191272441616\n            ],\n            [\n              -80.43777465820312,\n              25.25960064916269\n            ],\n            [\n              -80.44464111328125,\n              25.29437116258816\n            ],\n            [\n              -80.57098388671874,\n              25.2918878849706\n            ],\n            [\n              -80.56549072265625,\n              25.41722976060518\n            ],\n            [\n              -80.54489135742188,\n              25.575891798572776\n            ],\n            [\n              -80.4803466796875,\n              25.667522551344298\n            ],\n            [\n              -80.48446655273438,\n              25.890114046690094\n            ],\n            [\n              -80.43090820312499,\n              25.94816628853973\n            ],\n            [\n              -80.43365478515625,\n              26.10612083235552\n            ],\n            [\n              -80.44326782226562,\n              26.145576207592274\n            ],\n            [\n              -80.34576416015625,\n              26.12091815959972\n            ],\n            [\n              -80.34439086914062,\n              26.144343428856374\n            ],\n            [\n              -80.29220581054688,\n              26.1899475672235\n            ],\n            [\n              -80.28945922851562,\n              26.351267272877074\n            ],\n            [\n              -80.24139404296875,\n              26.341422119377988\n            ],\n            [\n              -80.20156860351562,\n              26.48532391504829\n            ],\n            [\n              -80.20706176757812,\n              26.518506504902675\n            ],\n            [\n              -80.23040771484375,\n              26.583614813585854\n            ],\n            [\n              -80.29632568359375,\n              26.686729520004036\n            ],\n            [\n              -80.44876098632812,\n              26.681821407205977\n            ],\n            [\n              -80.46798706054688,\n              26.517277690994334\n            ],\n            [\n              -80.49819946289062,\n              26.39925039312297\n            ],\n            [\n              -80.58609008789062,\n              26.395560091430248\n            ],\n            [\n              -80.65750122070312,\n              26.493927728762568\n            ],\n            [\n              -80.80581665039062,\n              26.496385842983383\n            ],\n            [\n              -80.8538818359375,\n              26.480407161007275\n            ],\n            [\n              -80.958251953125,\n              26.466885003671486\n            ],\n            [\n              -80.98434448242186,\n              26.436146919246013\n            ],\n            [\n              -80.9857177734375,\n              26.261399213411483\n            ],\n            [\n              -81.38534545898438,\n              26.257704515406648\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"10","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a441fe4b0c8380cd6689d","contributors":{"authors":[{"text":"Curnutt, J. L.","contributorId":97845,"corporation":false,"usgs":false,"family":"Curnutt","given":"J.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":392615,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Comiskey, J.","contributorId":54758,"corporation":false,"usgs":true,"family":"Comiskey","given":"J.","email":"","affiliations":[],"preferred":false,"id":392612,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nott, M.P.","contributorId":78677,"corporation":false,"usgs":true,"family":"Nott","given":"M.P.","email":"","affiliations":[],"preferred":false,"id":392614,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gross, L.J.","contributorId":65030,"corporation":false,"usgs":true,"family":"Gross","given":"L.J.","email":"","affiliations":[],"preferred":false,"id":392613,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022169,"text":"70022169 - 2000 - Fractionation of selenium isotopes during bacterial respiratory reduction of selenium oxyanions","interactions":[],"lastModifiedDate":"2018-12-12T08:49:02","indexId":"70022169","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Fractionation of selenium isotopes during bacterial respiratory reduction of selenium oxyanions","docAbstract":"<div id=\"abstracts\" class=\"Abstracts\"><div id=\"aep-abstract-id9\" class=\"abstract author\"><div id=\"aep-abstract-sec-id10\"><p>Reduction of selenium oxyanions by microorganisms is an important process in the biogeochemical cycling of selenium. Numerous bacteria can reduce Se oxyanions, which are used as electron acceptors during the oxidation of organic matter in anoxic environments. In this study, we used a double spike (<sup>82</sup>Se and<span>&nbsp;</span><sup>74</sup>Se) thermal ionization mass spectrometry technique to quantify the isotopic fractionation achieved by three different species of anaerobic bacteria capable of accomplishing growth by respiratory reduction of selenate [SeO<sub>4</sub><sup>2−</sup><span>&nbsp;</span>or Se(VI)] or selenite [SeO<sub>3</sub><sup>2−</sup><span>&nbsp;</span>or Se(IV)] to Se(IV) or elemental selenium [Se(0)] coupled with the oxidation of lactate. Isotopic discrimination in these closed system experiments was evaluated by Rayleigh fractionation equations and numerical models. Growing cultures of<span>&nbsp;</span><i>Bacillus selenitireducens</i>, a haloalkaliphile capable of growth using Se(IV) as an electron acceptor, induced a<span>&nbsp;</span><sup>80</sup>Se/<sup>76</sup>Se fractionation of −8.0 ± 0.4‰ (instantaneous ϵ value) during reduction of Se(IV) to Se(0). With<span>&nbsp;</span><i>Bacillus arsenicoselenatis</i>, a haloalkaliphile capable of growth using Se(VI) as an electron acceptor, fractionations of −5.0 ± 0.5‰ and −6.0 ± 1.0‰ were observed for reduction of Se(VI) to Se(IV) and reduction of Se(IV) to Se(0), respectively. In growing cultures of<span>&nbsp;</span><i>Sulfurospirillum barnesii</i>, a freshwater species capable of growth using Se(VI), fractionation was small initially, but near the end of the log growth phase, it increased to −4.0 ± 1.0‰ and −8.4 ± 0.4‰ for reduction of Se(VI) to Se(IV) and reduction of Se(IV) to Se(0), respectively. Washed cell suspensions of<span>&nbsp;</span><i>S. barnesii</i><span>&nbsp;</span>induced fractionations of −1.1 ± 0.4‰ during Se(VI) reduction, and −9.1 ± 0.5% for Se(IV) reduction, with some evidence for smaller values (e.g., −1.7‰) in the earliest-formed Se(0) results. These results demonstrate that dissimilatory reduction of selenate or selenite induces significant isotopic fractionation, and suggest that significant Se isotope ratio variation will be found in nature.</p></div></div></div>","language":"English","publisher":"Elsevier","doi":"10.1016/S0016-7037(00)00456-7","issn":"00167037","usgsCitation":"Herbel, M., Johnson, T., Oremland, R., and Bullen, T., 2000, Fractionation of selenium isotopes during bacterial respiratory reduction of selenium oxyanions: Geochimica et Cosmochimica Acta, v. 64, no. 21, p. 3701-3709, https://doi.org/10.1016/S0016-7037(00)00456-7.","productDescription":"9 p.","startPage":"3701","endPage":"3709","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230595,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"64","issue":"21","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a13abe4b0c8380cd5472d","contributors":{"authors":[{"text":"Herbel, M.J.","contributorId":57232,"corporation":false,"usgs":true,"family":"Herbel","given":"M.J.","email":"","affiliations":[],"preferred":false,"id":392596,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Johnson, T.M.","contributorId":22332,"corporation":false,"usgs":true,"family":"Johnson","given":"T.M.","affiliations":[],"preferred":false,"id":392595,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Oremland, R.S.","contributorId":97512,"corporation":false,"usgs":true,"family":"Oremland","given":"R.S.","email":"","affiliations":[],"preferred":false,"id":392598,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bullen, T.D.","contributorId":79911,"corporation":false,"usgs":true,"family":"Bullen","given":"T.D.","email":"","affiliations":[],"preferred":false,"id":392597,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022446,"text":"70022446 - 2000 - Effects of heterogeneity in aquifer permeability and biomass on biodegradation rate calculations: Results from numerical simulations","interactions":[],"lastModifiedDate":"2018-12-12T09:48:47","indexId":"70022446","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"Effects of heterogeneity in aquifer permeability and biomass on biodegradation rate calculations: Results from numerical simulations","docAbstract":"<p><span>Numerical simulations were used to examine the effects of heterogeneity in hydraulic conductivity (K) and intrinsic biodegradation rate on the accuracy of contaminant plume‐scale biodegradation rates obtained from field data. The simulations were based on a steady‐state BTEX contaminant plume undergoing biodegradation under sulfate‐reducing conditions, with the electron acceptor in excess. Biomass was either uniform or correlated with K to model spatially variable intrinsic biodegradation rates. A hydraulic conductivity data set from an alluvial aquifer was used to generate three sets of 10 realizations with different degrees of heterogeneity, and contaminant transport with biodegradation was simulated with BIOMOC. Biodegradation rates were calculated from the steady‐state contaminant plumes using decrease in concentration with distance downgradient and a single flow velocity estimate, as is commonly done in site characterization to support the interpretation of natural attenuation. The observed rates were found to underestimate the actual rate specified in the heterogeneous model in all cases. The discrepancy between the observed rate and the “true” rate depended on the ground water flow velocity estimate, and increased with increasing heterogeneity in the aquifer. For a lognormal K distribution with variance of 0.46, the estimate was no more than a factor of 1.4 slower than the true rate. For an aquifer with 20% silt/clay lenses, the rate estimate was as much as nine times slower than the true rate. Homogeneous‐permeability, uniform‐degradation rate simulations were used to generate predictions of remediation time with the rates estimated from the heterogeneous models. The homogeneous models generally overestimated the extent of remediation or underestimated remediation time, due to delayed degradation of contaminants in the low‐K areas. Results suggest that aquifer characterization for natural attenuation at contaminated sites should include assessment of the presence and extent of, and contaminant concentrations in, low‐permeability areas of an aquifer.</span></p>","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2000.tb02706.x","issn":"0017467X","usgsCitation":"Scholl, M.A., 2000, Effects of heterogeneity in aquifer permeability and biomass on biodegradation rate calculations: Results from numerical simulations: Ground Water, v. 38, no. 5, p. 702-712, https://doi.org/10.1111/j.1745-6584.2000.tb02706.x.","productDescription":"11 p.","startPage":"702","endPage":"712","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230682,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"38","issue":"5","noUsgsAuthors":false,"publicationDate":"2005-12-13","publicationStatus":"PW","scienceBaseUri":"505a0711e4b0c8380cd5153f","contributors":{"authors":[{"text":"Scholl, Martha A. 0000-0001-6994-4614 mascholl@usgs.gov","orcid":"https://orcid.org/0000-0001-6994-4614","contributorId":1920,"corporation":false,"usgs":true,"family":"Scholl","given":"Martha","email":"mascholl@usgs.gov","middleInitial":"A.","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":true,"id":393648,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70022118,"text":"70022118 - 2000 - The significance of microbial processes in hydrogeology and geochemistry","interactions":[],"lastModifiedDate":"2018-12-07T07:08:17","indexId":"70022118","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"The significance of microbial processes in hydrogeology and geochemistry","docAbstract":"Microbial processes affect the chemical composition of groundwater and the hydraulic properties of aquifers in both contaminated and pristine groundwater systems. The patterns of water-chemistry changes that occur depend upon the relative abundance of electron donors and electron acceptors. In many pristine aquifers, where microbial metabolism is limited by the availability of electron donors (usually organic matter), dissolved inorganic carbon (DIC) accumulates slowly along aquifer flow paths and available electron acceptors are consumed sequentially in the order dissolved oxygen > nitrate > Fe(III) > sulfate > CO2 (methanogenesis). In aquifers contaminated by anthropogenic contaminants, an excess of available organic carbon often exists, and microbial metabolism is limited by the availability of electron acceptors. In addition to changes in groundwater chemistry, the solid matrix of the aquifer is affected by microbial processes. The production of carbon dioxide and organic acids can lead to increased mineral solubility, which can lead to the development of secondary porosity and permeability. Conversely, microbial production of carbonate, ferrous iron, and sulfide can result in the precipitation of secondary calcite or pyrite cements that reduce primary porosity and permeability in groundwater systems.","language":"English","publisher":"Springer","doi":"10.1007/PL00010973","issn":"14312174","usgsCitation":"Chapelle, F.H., 2000, The significance of microbial processes in hydrogeology and geochemistry: Hydrogeology Journal, v. 8, no. 1, p. 41-46, https://doi.org/10.1007/PL00010973.","productDescription":"6 p.","startPage":"41","endPage":"46","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230442,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"8","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb031e4b08c986b324cb5","contributors":{"authors":[{"text":"Chapelle, F. H.","contributorId":101697,"corporation":false,"usgs":true,"family":"Chapelle","given":"F.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":392431,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70022442,"text":"70022442 - 2000 - Methodology and application of combined watershed and ground-water models in Kansas","interactions":[],"lastModifiedDate":"2012-03-12T17:19:43","indexId":"70022442","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Methodology and application of combined watershed and ground-water models in Kansas","docAbstract":"Increased irrigation in Kansas and other regions during the last several decades has caused serious water depletion, making the development of comprehensive strategies and tools to resolve such problems increasingly important. This paper makes the case for an intermediate complexity, quasi-distributed, comprehensive, large-watershed model, which falls between the fully distributed, physically based hydrological modeling system of the type of the SHE model and the lumped, conceptual rainfall-runoff modeling system of the type of the Stanford watershed model. This is achieved by integrating the quasi-distributed watershed model SWAT with the fully-distributed ground-water model MODFLOW. The advantage of this approach is the appreciably smaller input data requirements and the use of readily available data (compared to the fully distributed, physically based models), the statistical handling of watershed heterogeneities by employing the hydrologic-response-unit concept, and the significantly increased flexibility in handling stream-aquifer interactions, distributed well withdrawals, and multiple land uses. The mechanics of integrating the component watershed and ground-water models are outlined, and three real-world management applications of the integrated model from Kansas are briefly presented. Three different aspects of the integrated model are emphasized: (1) management applications of a Decision Support System for the integrated model (Rattlesnake Creek subbasin); (2) alternative conceptual models of spatial heterogeneity related to the presence or absence of an underlying aquifer with shallow or deep water table (Lower Republican River basin); and (3) the general nature of the integrated model linkage by employing a watershed simulator other than SWAT (Wet Walnut Creek basin). These applications demonstrate the practicality and versatility of this relatively simple and conceptually clear approach, making public acceptance of the integrated watershed modeling system much easier. This approach also enhances model calibration and thus the reliability of model results. (C) 2000 Elsevier Science B.V.Increased irrigation in Kansas and other regions during the last several decades has caused serious water depletion, making the development of comprehensive strategies and tools to resolve such problems increasingly important. This paper makes the case for an intermediate complexity, quasi-distributed, comprehensive, large-watershed model, which falls between the fully distributed, physically based hydrological modeling system of the type of the SHE model and the lumped, conceptual rainfall-runoff modeling system of the type of the Stanford watershed model. This is achieved by integrating the quasi-distributed watershed model SWAT with the fully-distributed ground-water model MODFLOW. The advantage of this approach is the appreciably smaller input data requirements and the use of readily available data (compared to the fully distributed, physically based models), the statistical handling of watershed heterogeneities by employing the hydrologic-response-unit concept, and the significantly increased flexibility in handling stream-aquifer interactions, distributed well withdrawals, and multiple land uses. The mechanics of integrating the component watershed and ground-water models are outlined, and three real-world management applications of the integrated model from Kansas are briefly presented. Three different aspects of the integrated model are emphasized: (1) management applications of a Decision Support System for the integrated model (Rattlesnake Creek subbasin); (2) alternative conceptual models of spatial heterogeneity related to the presence or absence of an underlying aquifer with shallow or deep water table (Lower Republican River basin); and (3) the general nature of the integrated model linkage by employing a watershed simulator other than SWAT (Wet Walnut Creek basin). These applications demonstrate the practicality and ve","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Science B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0022-1694(00)00293-6","issn":"00221694","usgsCitation":"Sophocleous, M., and Perkins, S., 2000, Methodology and application of combined watershed and ground-water models in Kansas: Journal of Hydrology, v. 236, no. 3-4, p. 185-201, https://doi.org/10.1016/S0022-1694(00)00293-6.","startPage":"185","endPage":"201","numberOfPages":"17","costCenters":[],"links":[{"id":206714,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(00)00293-6"},{"id":230613,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"236","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a556ce4b0c8380cd6d1e3","contributors":{"authors":[{"text":"Sophocleous, M.","contributorId":13373,"corporation":false,"usgs":true,"family":"Sophocleous","given":"M.","email":"","affiliations":[],"preferred":false,"id":393639,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Perkins, S.P.","contributorId":12211,"corporation":false,"usgs":true,"family":"Perkins","given":"S.P.","email":"","affiliations":[],"preferred":false,"id":393638,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70023103,"text":"70023103 - 2000 - Metal exposure in a benthic macroinvertebrate, Hydropsyche californica, related to mine drainage in the Sacramento River","interactions":[],"lastModifiedDate":"2018-12-07T05:51:27","indexId":"70023103","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1169,"text":"Canadian Journal of Fisheries and Aquatic Sciences","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Metal exposure in a benthic macroinvertebrate, <i>Hydropsyche californica</i>, related to mine drainage in the Sacramento River","title":"Metal exposure in a benthic macroinvertebrate, Hydropsyche californica, related to mine drainage in the Sacramento River","docAbstract":"<p><span>A biomonitoring technique was employed to complement studies of metal transport in the upper Sacramento River affected by acid mine drainage. Metals (Al, Cd, Cu, Fe, Hg, Pb, and Zn) were determined in a resident invertebrate,&nbsp;</span><i>Hydropsyche californica</i><span><span>&nbsp;</span>(Insecta: Trichoptera), and streambed sediments (&lt;62 µm) to assess metal contamination within a 111-km section of the river downstream of the mining area. Metals in<span>&nbsp;</span></span><i>H. californica</i><span><span>&nbsp;</span>also were interpreted to be broadly indicative of metal exposure in fish. Total Hg was determined in the whole body of the insect, whereas Al, Cd, Cu, Fe, Pb, and Zn were additionally separated into operationally defined cytosolic (used as an indicator of exposure to bioavailable metal) and particulate fractions. Total concentrations of Cd, Cu, Hg, Pb, and Zn in sediments were consistent with documented upstream sources of acid mine drainage. Metal distribution patterns in<span>&nbsp;</span></span><i>H. californica</i><span><span>&nbsp;</span>and sediments were generally consistent for Cd, Cu, and Pb but inconsistent for Hg and Zn. Concentrations in<span>&nbsp;</span></span><i>H. californica</i><span><span>&nbsp;</span>indicated that bioavailable Cd, Cu, Pb, and Zn was transported at least 120 km downstream of the mine sources. Zinc in<span>&nbsp;</span></span><i>H. californica</i><span><span>&nbsp;</span>was elevated, but unlike sediments, did not decrease downstream. Mercury in<span>&nbsp;</span></span><i>H. californica</i><span><span>&nbsp;</span>was not elevated.</span></p>","language":"English","publisher":"NRC Research Press","doi":"10.1139/f99-260","usgsCitation":"Cain, D.J., Carter, J.L., Fend, S.V., Luoma, S.N., Alpers, C.N., and Taylor, H.E., 2000, Metal exposure in a benthic macroinvertebrate, Hydropsyche californica, related to mine drainage in the Sacramento River: Canadian Journal of Fisheries and Aquatic Sciences, v. 57, no. 2, p. 380-390, https://doi.org/10.1139/f99-260.","productDescription":"11 p.","startPage":"380","endPage":"390","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"links":[{"id":233625,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Sacramento River","volume":"57","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a547de4b0c8380cd6cfbf","contributors":{"authors":[{"text":"Cain, Daniel J. 0000-0002-3443-0493 djcain@usgs.gov","orcid":"https://orcid.org/0000-0002-3443-0493","contributorId":1784,"corporation":false,"usgs":true,"family":"Cain","given":"Daniel","email":"djcain@usgs.gov","middleInitial":"J.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":true,"id":396177,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Carter, James L. 0000-0002-0104-9776 jlcarter@usgs.gov","orcid":"https://orcid.org/0000-0002-0104-9776","contributorId":3278,"corporation":false,"usgs":true,"family":"Carter","given":"James","email":"jlcarter@usgs.gov","middleInitial":"L.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":396175,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Fend, Steven V. 0000-0002-4638-6602 svfend@usgs.gov","orcid":"https://orcid.org/0000-0002-4638-6602","contributorId":3591,"corporation":false,"usgs":true,"family":"Fend","given":"Steven","email":"svfend@usgs.gov","middleInitial":"V.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":396179,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Luoma, Samuel N. 0000-0001-5443-5091 snluoma@usgs.gov","orcid":"https://orcid.org/0000-0001-5443-5091","contributorId":2287,"corporation":false,"usgs":true,"family":"Luoma","given":"Samuel","email":"snluoma@usgs.gov","middleInitial":"N.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":396178,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Alpers, Charles N. 0000-0001-6945-7365 cnalpers@usgs.gov","orcid":"https://orcid.org/0000-0001-6945-7365","contributorId":411,"corporation":false,"usgs":true,"family":"Alpers","given":"Charles","email":"cnalpers@usgs.gov","middleInitial":"N.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":396180,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Taylor, Howard E. hetaylor@usgs.gov","contributorId":1551,"corporation":false,"usgs":true,"family":"Taylor","given":"Howard","email":"hetaylor@usgs.gov","middleInitial":"E.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":396176,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70022761,"text":"70022761 - 2000 - Analysis of selected herbicide metabolites in surface and ground water of the United States","interactions":[],"lastModifiedDate":"2018-12-07T06:16:43","indexId":"70022761","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3352,"text":"Science of the Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Analysis of selected herbicide metabolites in surface and ground water of the United States","docAbstract":"<div id=\"abstracts\" class=\"Abstracts\"><div id=\"aep-abstract-id10\" class=\"abstract author\"><div id=\"aep-abstract-sec-id11\"><p>One of the primary goals of the US Geological Survey (USGS) Laboratory in Lawrence, Kansas, is to develop analytical methods for the analysis of herbicide metabolites in surface and ground water that are vital to the study of herbicide fate and degradation pathways in the environment. Methods to measure metabolite concentrations from three major classes of herbicides — triazine, chloroacetanilide and phenyl-urea — have been developed. Methods for triazine metabolite detection cover nine compounds: six compounds are detected by gas chromatography/mass spectrometry; one is detected by high-performance liquid chromatography with diode-array detection; and eight are detected by liquid chromatography/mass spectrometry. Two metabolites of the chloroacetanilide herbicides — ethane sulfonic acid and oxanilic acid — are detected by high-performance liquid chromatography with diode-array detection and liquid chromatography/mass spectrometry. Alachlor ethane sulfonic acid also has been detected by solid-phase extraction and enzyme-linked immunosorbent assay. Six phenylurea metabolites are all detected by liquid chromatography/mass spectrometry; four of the six metabolites also are detected by gas chromatography/mass spectrometry. Additionally, surveys of herbicides and their metabolites in surface water, ground water, lakes, reservoirs, and rainfall have been conducted through the USGS laboratory in Lawrence. These surveys have been useful in determining herbicide and metabolite occurrence and temporal distribution and have shown that metabolites may be useful in evaluation of non-point-source contamination.</p></div></div></div>","language":"English","publisher":"Elsevier","doi":"10.1016/S0048-9697(99)00539-2","issn":"00489697","usgsCitation":"Scribner, E., Thurman, E., and Zimmerman, L., 2000, Analysis of selected herbicide metabolites in surface and ground water of the United States: Science of the Total Environment, v. 248, no. 2-3, p. 157-167, https://doi.org/10.1016/S0048-9697(99)00539-2.","productDescription":"11 p.","startPage":"157","endPage":"167","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233490,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208078,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0048-9697(99)00539-2"}],"volume":"248","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059eb2ee4b0c8380cd48c87","contributors":{"authors":[{"text":"Scribner, E.A.","contributorId":50925,"corporation":false,"usgs":true,"family":"Scribner","given":"E.A.","email":"","affiliations":[],"preferred":false,"id":394812,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":394813,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Zimmerman, L.R.","contributorId":28624,"corporation":false,"usgs":true,"family":"Zimmerman","given":"L.R.","email":"","affiliations":[],"preferred":false,"id":394811,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022762,"text":"70022762 - 2000 - Use of radioimmunoassay as a screen for antibiotics in confined animal feeding operations and confirmation by liquid chromatography/mass spectrometry","interactions":[],"lastModifiedDate":"2018-12-12T09:06:48","indexId":"70022762","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":5331,"text":"Science of Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Use of radioimmunoassay as a screen for antibiotics in confined animal feeding operations and confirmation by liquid chromatography/mass spectrometry","docAbstract":"<p>Approximately one-half of the 50 000000 lb of antibiotics produced in the USA are used in agriculture. Because of the intensive use of antibiotics in the management of confined livestock operations, the potential exists for the transport of these compounds and their metabolites into our nation's water resources. A commercially available radioimmunoassay method, developed as a screen for tetracycline antibiotics in serum, urine, milk, and tissue, was adapted to analyze water samples at a detection level of approximately 1.0 ppb and a semiquantitative analytical range of 1-20 ppb. Liquid waste samples were obtained from 13 hog lagoons in three states and 52 surface- and ground-water samples were obtained primarily from areas associated with intensive swine and poultry production in seven states. These samples were screened for the tetracycline antibiotics by using the modified radioimmunoassay screening method. The radioimmunoassay tests yielded positive results for tetracycline antibiotics in samples from all 13 of the hog lagoons. Dilutions of 10-100-fold of the hog lagoon samples indicated that tetracycline antibiotic concentrations ranged from approximately 5 to several hundred parts per billion in liquid hog lagoon waste. Of the 52 surface- and ground-water samples collected all but two tested negative and these two samples contained tetracycline antibiotic concentrations less than 1 ppb. A new liquid chromatography/mass spectrometry method was used to confirm the radioimmunoassay results in 9 samples and also to identify the tetracycline antibiotics to which the radioimmunoassay test was responding. The new liquid chromatography/mass spectrometry method with online solid-phase extraction and a detection level of 0.5 ??g/l confirmed the presence of chlorotetracycline in the hog lagoon samples and in one of the surface-water samples. The concentrations calculated from the radioimmunoassay were a factor of 1-5 times less than those calculated by the liquid chromatography/mass spectrometry concentrations for chlorotetracycline.&nbsp;</p>","language":"English","publisher":"Elsevier","doi":"10.1016/S0048-9697(99)00541-0","issn":"00489697","usgsCitation":"Meyer, M.T., Bumgarner, J., Varns, J., Daughtridge, J., Thurman, E., and Hostetler, K., 2000, Use of radioimmunoassay as a screen for antibiotics in confined animal feeding operations and confirmation by liquid chromatography/mass spectrometry: Science of Total Environment, v. 248, no. 2-3, p. 181-187, https://doi.org/10.1016/S0048-9697(99)00541-0.","productDescription":"7 p.","startPage":"181","endPage":"187","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":208079,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0048-9697(99)00541-0"},{"id":233491,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"248","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bbf64e4b08c986b329b25","contributors":{"authors":[{"text":"Meyer, M. T.","contributorId":92279,"corporation":false,"usgs":true,"family":"Meyer","given":"M.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":394818,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bumgarner, J.E.","contributorId":82410,"corporation":false,"usgs":true,"family":"Bumgarner","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":394816,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Varns, J.L.","contributorId":85369,"corporation":false,"usgs":true,"family":"Varns","given":"J.L.","affiliations":[],"preferred":false,"id":394817,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Daughtridge, J.V.","contributorId":69335,"corporation":false,"usgs":true,"family":"Daughtridge","given":"J.V.","email":"","affiliations":[],"preferred":false,"id":394815,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":394819,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Hostetler, K.A.","contributorId":29855,"corporation":false,"usgs":true,"family":"Hostetler","given":"K.A.","email":"","affiliations":[],"preferred":false,"id":394814,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70022810,"text":"70022810 - 2000 - Occurrence of sulfonylurea, sulfonamide, imidazolinone, and other herbicides in rivers, reservoirs and ground water in the Midwestern United States, 1998","interactions":[],"lastModifiedDate":"2021-05-27T18:38:56.616138","indexId":"70022810","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":5331,"text":"Science of Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Occurrence of sulfonylurea, sulfonamide, imidazolinone, and other herbicides in rivers, reservoirs and ground water in the Midwestern United States, 1998","docAbstract":"<div id=\"abstracts\" class=\"Abstracts\"><div id=\"aep-abstract-id10\" class=\"abstract author\"><div id=\"aep-abstract-sec-id11\"><p>Sulfonylurea (SU), sulfonamide (SA), and imidazolinone (IMI) herbicides are relatively new classes of chemical compounds that function by inhibiting the action of a plant enzyme, stopping plant growth, and eventually killing the plant. These compounds generally have low mammalian toxicity, but plants demonstrate a wide range in sensitivity to SUs, SAs, and IMIs with over a 10&nbsp;000-fold difference in observed toxicity levels for some compounds. SUs, SAs, and IMIs are applied either pre- or post-emergence to crops commonly at 1/50th or less of the rate of other herbicides. Little is known about their occurrence, fate, or transport in surface water or ground water in the USA. To obtain information on the occurrence of SU, SA, and IMI herbicides in the Midwestern United States, 212 water samples were collected from 75 surface-water and 25 ground-water sites in 1998. These samples were analyzed for 16 SU, SA and IMI herbicides by USGS Methods Research and Development Program staff using high-performance liquid chromatography/mass spectrometry. Samples were also analyzed for 47 pesticides or pesticide degradation products. At least one of the 16 SUs, SAs or IMIs was detected above the method reporting limit (MRL) of 0.01 μg/l in 83% of 130 stream samples. Imazethapyr was detected most frequently (71% of samples) followed by flumetsulam (63% of samples) and nicosulfuron (52% of samples). The sum of SU, SA and IMI concentrations exceeded 0.5 μg/l in less than 10% of stream samples. Acetochlor, alachlor, atrazine, cyanazine and metolachlor were all detected in 90% or more of 129 stream samples. The sum of the concentration of these five herbicides exceeded 50 μg/l in approximately 10% of stream samples. At least one SU, SA, or IMI herbicide was detected above the MRL in 24% of 25 ground-water samples and 86% of seven reservoir samples.</p></div></div></div>","language":"English","publisher":"Elsevier","doi":"10.1016/S0048-9697(99)00536-7","issn":"00489697","usgsCitation":"Battaglin, W., Furlong, E., Burkhardt, M., and Peter, C., 2000, Occurrence of sulfonylurea, sulfonamide, imidazolinone, and other herbicides in rivers, reservoirs and ground water in the Midwestern United States, 1998: Science of Total Environment, v. 248, no. 2-3, p. 123-133, https://doi.org/10.1016/S0048-9697(99)00536-7.","productDescription":"11 p.","startPage":"123","endPage":"133","costCenters":[{"id":452,"text":"National Water Quality Laboratory","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":208183,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0048-9697(99)00536-7"},{"id":233715,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"248","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6c37e4b0c8380cd74af2","contributors":{"authors":[{"text":"Battaglin, W.A.","contributorId":16376,"corporation":false,"usgs":true,"family":"Battaglin","given":"W.A.","email":"","affiliations":[],"preferred":false,"id":394975,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Furlong, E. T. 0000-0002-7305-4603","orcid":"https://orcid.org/0000-0002-7305-4603","contributorId":98346,"corporation":false,"usgs":true,"family":"Furlong","given":"E. T.","affiliations":[],"preferred":false,"id":394978,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Burkhardt, M.R.","contributorId":70410,"corporation":false,"usgs":true,"family":"Burkhardt","given":"M.R.","email":"","affiliations":[],"preferred":false,"id":394977,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Peter, C.J.","contributorId":43538,"corporation":false,"usgs":true,"family":"Peter","given":"C.J.","email":"","affiliations":[],"preferred":false,"id":394976,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70022815,"text":"70022815 - 2000 - An evaluation of the Wyoming Gauge System for snowfall measurement","interactions":[],"lastModifiedDate":"2018-03-27T17:03:11","indexId":"70022815","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"An evaluation of the Wyoming Gauge System for snowfall measurement","docAbstract":"<p><span>The Wyoming snow fence (shield) has been widely used with precipitation gauges for snowfall measurement at more than 25 locations in Alaska since the late 1970s. This gauge's measurements have been taken as the reference for correcting wind‐induced gauge undercatch of snowfall in Alaska. Recently, this fence (shield) was tested in the World Meteorological Organization Solid Precipitation Measurement Intercomparison Project at four locations in the United States of America and Canada for six winter seasons. At the Intercomparison sites an octagonal vertical Double Fence with a Russian Tretyakov gauge or a Universal Belfort recording gauge was installed and used as the Intercomparison Reference (DFIR) to provide true snowfall amounts for this Intercomparison experiment. The Intercomparison data collected were compiled at the four sites that represent a variety of climate, terrain, and exposure. On the basis of these data sets the performance of the Wyoming gauge system for snowfall observations was carefully evaluated against the DFIR and snow cover data. The results show that (1) the mean snow catch efficiency of the Wyoming gauge compared with the DFIR is about 80–90%, (2) there exists a close linear relation between the measurements of the two gauge systems and this relation may serve as a transfer function to adjust the Wyoming gauge records to obtain an estimate of the true snowfall amount, (3) catch efficiency of the Wyoming gauge does not change with wind speed and temperature, and (4) Wyoming gauge measurements are generally compatible to the snowpack water equivalent at selected locations in northern Alaska. These results are important to our effort of determining true snowfall amounts in the high latitudes, and they are also useful for regional hydrologic and climatic analyses.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000WR900158","usgsCitation":"Yang, D., Kane, D.L., Hinzman, L.D., Goodison, B.E., Metcalfe, J.R., Louie, P.Y., Leavesley, G.H., Emerson, D.G., and Hanson, C.L., 2000, An evaluation of the Wyoming Gauge System for snowfall measurement: Water Resources Research, v. 36, no. 9, p. 2665-2677, https://doi.org/10.1029/2000WR900158.","productDescription":"13 p.","startPage":"2665","endPage":"2677","costCenters":[{"id":478,"text":"North Dakota Water Science Center","active":true,"usgs":true},{"id":34685,"text":"Dakota Water Science Center","active":true,"usgs":true}],"links":[{"id":233790,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"9","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"5059ea54e4b0c8380cd487b3","contributors":{"authors":[{"text":"Yang, Daqing","contributorId":203286,"corporation":false,"usgs":false,"family":"Yang","given":"Daqing","email":"","affiliations":[],"preferred":false,"id":394995,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kane, Douglas L.","contributorId":112099,"corporation":false,"usgs":true,"family":"Kane","given":"Douglas","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":394990,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hinzman, Larry D.","contributorId":97133,"corporation":false,"usgs":true,"family":"Hinzman","given":"Larry","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":394997,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Goodison, Barry E.","contributorId":203293,"corporation":false,"usgs":false,"family":"Goodison","given":"Barry","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":394996,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Metcalfe, John R.","contributorId":203294,"corporation":false,"usgs":false,"family":"Metcalfe","given":"John","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":394991,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Louie, Paul Y.T.","contributorId":60419,"corporation":false,"usgs":false,"family":"Louie","given":"Paul","email":"","middleInitial":"Y.T.","affiliations":[],"preferred":false,"id":394993,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Leavesley, George H. george@usgs.gov","contributorId":1202,"corporation":false,"usgs":true,"family":"Leavesley","given":"George","email":"george@usgs.gov","middleInitial":"H.","affiliations":[],"preferred":true,"id":394998,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Emerson, Douglas G.","contributorId":40579,"corporation":false,"usgs":true,"family":"Emerson","given":"Douglas","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":394992,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Hanson, Clayton L.","contributorId":203290,"corporation":false,"usgs":false,"family":"Hanson","given":"Clayton","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":394994,"contributorType":{"id":1,"text":"Authors"},"rank":9}]}}
,{"id":70022623,"text":"70022623 - 2000 - A field technique for estimating aquifer parameters using flow log data","interactions":[],"lastModifiedDate":"2018-12-10T07:27:11","indexId":"70022623","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"A field technique for estimating aquifer parameters using flow log data","docAbstract":"A numerical model is used to predict flow along intervals between producing zones in open boreholes for comparison with measurements of borehole flow. The model gives flow under quasi-steady conditions as a function of the transmissivity and hydraulic head in an arbitrary number of zones communicating with each other along open boreholes. The theory shows that the amount of inflow to or outflow from the borehole under any one flow condition may not indicate relative zone transmissivity. A unique inversion for both hydraulic-head and transmissivity values is possible if flow is measured under two different conditions such as ambient and quasi-steady pumping, and if the difference in open-borehole water level between the two flow conditions is measured. The technique is shown to give useful estimates of water levels and transmissivities of two or more water-producing zones intersecting a single interval of open borehole under typical field conditions. Although the modeling technique involves some approximation, the principle limit on the accuracy of the method under field conditions is the measurement error in the flow log data. Flow measurements and pumping conditions are usually adjusted so that transmissivity estimates are most accurate for the most transmissive zones, and relative measurement error is proportionately larger for less transmissive zones. The most effective general application of the borehole-flow model results when the data are fit to models that systematically include more production zones of progressively smaller transmissivity values until model results show that all accuracy in the data set is exhausted.A numerical model is used to predict flow along intervals between producing zones in open boreholes for comparison with measurements of borehole flow. The model gives flow under quasi-steady conditions as a function of the transmissivity and hydraulic head in an arbitrary number of zones communicating with each other along open boreholes. The theory shows that the amount of inflow to or outflow from the borehole under any one flow condition may not indicate relative zone transmissivity. A unique inversion for both hydraulic-head and transmissivity values is possible if flow is measured under two different conditions such as ambient and quasi-steady pumping, and if the difference in open-borehole water level between the two flow conditions is measured. The technique is shown to give useful estimates of water levels and transmissivities of two or more water-producing zones intersecting a single interval of open borehole under typical field conditions. Although the modeling technique involves some approximation, the principle limit on the accuracy of the method under field conditions is the measurement error in the flow log data. Flow measurements and pumping conditions are usually adjusted so that transmissivity estimates are most accurate for the most transmissive zones, and relative measurement error is proportionately larger for less transmissive zones. The most effective general application of the borehole-flow model results when the data are fit to models that symmetrically include more production zones of progressively smaller transmissivity values until model results show that all accuracy in the data set is exhausted.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2000.tb00243.x","issn":"0017467X","usgsCitation":"Paillet, F.L., 2000, A field technique for estimating aquifer parameters using flow log data: Ground Water, v. 38, no. 4, p. 510-521, https://doi.org/10.1111/j.1745-6584.2000.tb00243.x.","productDescription":"12 p.","startPage":"510","endPage":"521","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230473,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"38","issue":"4","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"5059e3d6e4b0c8380cd4624d","contributors":{"authors":[{"text":"Paillet, Frederick L.","contributorId":63820,"corporation":false,"usgs":true,"family":"Paillet","given":"Frederick","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":394289,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70022591,"text":"70022591 - 2000 - REE speciation in low-temperature acidic waters and the competitive effects of aluminum","interactions":[],"lastModifiedDate":"2018-12-12T08:45:04","indexId":"70022591","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1213,"text":"Chemical Geology","active":true,"publicationSubtype":{"id":10}},"title":"REE speciation in low-temperature acidic waters and the competitive effects of aluminum","docAbstract":"<p>The effect of simultaneous competitive speciation of dissolved rare earth elements (REEs) in acidic waters (pH 3.3 to 5.2) has been evaluated by applying the PHREEQE code to the speciation of water analyses from Spain, Brazil, USA, and Canada. The main ions that might affect REE are Al3+, F-, SO42-, and PO43-. Fluoride, normally a significant complexer of REEs, is strongly associated with Al3+ in acid waters and consequently has little influence on REEs. The inclusion of aluminum concentrations in speciation calculations for acidic waters is essential for reliable speciation of REEs. Phosphate concentrations are too low (10-4 to 10-7 m) to affect REE speciation. Consequently, SO42- is the only important complexing ligand for REEs under these conditions. According to Millero [Millero, F.J., 1992. Stability constants for the formation of rare earth inorganic complexes as a function of ionic strength. Geochim. Cosmochim. Acta, 56, 3123-3132], the lanthanide sulfate stability constants are nearly constant with increasing atomic number so that no REE fractionation would be anticipated from aqueous complexation in acidic waters. Hence, REE enrichments or depletions must arise from mass transfer reactions.&nbsp;</p>","language":"English","publisher":"Elsevier","doi":"10.1016/S0009-2541(99)00166-7","issn":"00092541","usgsCitation":"Gimeno, S.M., Auque, S.L., and Nordstrom, D.K., 2000, REE speciation in low-temperature acidic waters and the competitive effects of aluminum: Chemical Geology, v. 165, no. 3-4, p. 167-180, https://doi.org/10.1016/S0009-2541(99)00166-7.","productDescription":"14 p.","startPage":"167","endPage":"180","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230547,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206683,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0009-2541(99)00166-7"}],"volume":"165","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a9339e4b0c8380cd80cb1","contributors":{"authors":[{"text":"Gimeno, Serrano M.J.","contributorId":82182,"corporation":false,"usgs":true,"family":"Gimeno","given":"Serrano","email":"","middleInitial":"M.J.","affiliations":[],"preferred":false,"id":394178,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Auque, Sanz L.F.","contributorId":47245,"corporation":false,"usgs":true,"family":"Auque","given":"Sanz","email":"","middleInitial":"L.F.","affiliations":[],"preferred":false,"id":394177,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nordstrom, D. Kirk 0000-0003-3283-5136 dkn@usgs.gov","orcid":"https://orcid.org/0000-0003-3283-5136","contributorId":749,"corporation":false,"usgs":true,"family":"Nordstrom","given":"D.","email":"dkn@usgs.gov","middleInitial":"Kirk","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":false,"id":394179,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70022058,"text":"70022058 - 2000 - Water quality degradation effects on freshwater availability: Impacts of human activities","interactions":[],"lastModifiedDate":"2022-06-28T15:37:25.188589","indexId":"70022058","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3713,"text":"Water International","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Water quality degradation effects on freshwater availability: <i>Impacts of human activities</i>","title":"Water quality degradation effects on freshwater availability: Impacts of human activities","docAbstract":"The quality of freshwater at any point on the landscape reflects the combined effects of many processes along water pathways. Human activities on all spatial scales affect both water quality and quantity. Alteration of the landscape and associated vegetation has not only changed the water balance, but typically has altered processes that control water quality. Effects of human activities on a small scale are relevant to an entire drainage basin. Furthermore, local, regional, and global differences in climate and water flow are considerable, causing varying effects of human activities on land and water quality and quantity, depending on location within a watershed, geology, biology, physiographic characteristics, and climate. These natural characteristics also greatly control human activities, which will, in turn, modify (or affect) the natural composition of water. One of the most important issues for effective resource management is recognition of cyclical and cascading effects of human activities on the water quality and quantity along hydrologic pathways. The degradation of water quality in one part of a watershed can have negative effects on users downstream. Everyone lives downstream of the effects of some human activity. An extremely important factor is that substances added to the atmosphere, land, and water generally have relatively long time scales for removal or clean up. The nature of the substance, including its affinity for adhering to soil and its ability to be transformed, affects the mobility and the time scale for removal of the substance. Policy alone will not solve many of the degradation issues, but a combination of policy, education, scientific knowledge, planning, and enforcement of applicable laws can provide mechanisms for slowing the rate of degradation and provide human and environmental protection. Such an integrated approach is needed to effectively manage land and water resources.","language":"English","publisher":"Taylor & Francis","doi":"10.1080/02508060008686817","issn":"02508060","usgsCitation":"Peters, N.E., and Meybeck, M., 2000, Water quality degradation effects on freshwater availability: Impacts of human activities: Water International, v. 25, no. 2, p. 185-193, https://doi.org/10.1080/02508060008686817.","productDescription":"9 p.","startPage":"185","endPage":"193","costCenters":[],"links":[{"id":230775,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc893e4b08c986b32c9d3","contributors":{"authors":[{"text":"Peters, Norman E. nepeters@usgs.gov","contributorId":1324,"corporation":false,"usgs":true,"family":"Peters","given":"Norman","email":"nepeters@usgs.gov","middleInitial":"E.","affiliations":[{"id":316,"text":"Georgia Water Science Center","active":true,"usgs":true}],"preferred":true,"id":392201,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Meybeck, Michel","contributorId":43521,"corporation":false,"usgs":true,"family":"Meybeck","given":"Michel","email":"","affiliations":[],"preferred":false,"id":392202,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":1002421,"text":"1002421 - 2000 - Climate change: Potential impacts and interactions in wetlands of the United States","interactions":[],"lastModifiedDate":"2019-06-03T15:48:00","indexId":"1002421","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Climate change: Potential impacts and interactions in wetlands of the United States","docAbstract":"Wetlands exist in a transition zone between aquatic and terrestrial environments which can be altered by subtle changes in hydrology. Twentieth century climate records show that the United States is generally experiencing a trend towards a wetter, warmer climate; some climate models suggest that his trend will continue and possibly intensify over the next 100 years. Wetlands that are most likely to be affected by these and other potential changes (e.g., sea-level rise) associated with atmospheric carbon enrichment include permafrost wetlands, coastal and estuarine wetlands, peatlands, alpine wetlands, and prairie pothote wetlands. Potential impacts range from changes in community structure to changes in ecological function, and from extirpation to enhancement. Wetlands (particularly boreal peatlands) play an important role in the global carbon cycle, generally sequestering carbon in the form of biomass, methane, dissolved organic material and organic sediment. Wetlands that are drained or partially dried can become a net source of methane and carbon dioxide to the atmosphere, serving as a positive biotic feedback to global warming. Policy options for minimizing the adverse impacts of climate change on wetland ecosystems include the reduction of current anthropogenic stresses, allowing for inland migration of coastal wetlands as sea-level rises, active management to preserve wetland hydrology, and a wide range of other management and restoration options.","language":"English","publisher":"Wiley","doi":"10.1111/j.1752-1688.2000.tb04270.x","usgsCitation":"Burkett, V., and Kusler, J., 2000, Climate change: Potential impacts and interactions in wetlands of the United States: Journal of the American Water Resources Association, v. 36, no. 2, p. 313-320, https://doi.org/10.1111/j.1752-1688.2000.tb04270.x.","productDescription":"8 p.","startPage":"313","endPage":"320","costCenters":[{"id":455,"text":"National Wetlands Research Center","active":true,"usgs":true},{"id":17705,"text":"Wetland and Aquatic Research Center","active":true,"usgs":true}],"links":[{"id":133991,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","volume":"36","issue":"2","noUsgsAuthors":false,"publicationDate":"2007-06-08","publicationStatus":"PW","scienceBaseUri":"4f4e49d6e4b07f02db5de1e7","contributors":{"authors":[{"text":"Burkett, Virginia 0000-0003-4746-2862 virginia_burkett@usgs.gov","orcid":"https://orcid.org/0000-0003-4746-2862","contributorId":2867,"corporation":false,"usgs":true,"family":"Burkett","given":"Virginia","email":"virginia_burkett@usgs.gov","affiliations":[{"id":505,"text":"Office of the AD Climate and Land-Use Change","active":true,"usgs":true}],"preferred":true,"id":312093,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kusler, Jon","contributorId":113716,"corporation":false,"usgs":true,"family":"Kusler","given":"Jon","affiliations":[],"preferred":false,"id":312092,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022817,"text":"70022817 - 2000 - Determination of chloroacetanilide herbicide metabolites in water using high-performance liquid chromatography-diode array detection and high-performance liquid chromatography/mass spectrometry","interactions":[],"lastModifiedDate":"2018-12-12T07:53:10","indexId":"70022817","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3352,"text":"Science of the Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Determination of chloroacetanilide herbicide metabolites in water using high-performance liquid chromatography-diode array detection and high-performance liquid chromatography/mass spectrometry","docAbstract":"<div id=\"abstracts\" class=\"Abstracts\"><div id=\"aep-abstract-id6\" class=\"abstract author\"><div id=\"aep-abstract-sec-id7\"><p>Analytical methods using high-performance liquid chromatography-diode array detection (HPLC-DAD) and high-performance liquid chromatography/mass spectrometry (HPLC/MS) were developed for the analysis of the following chloroacetanilide herbicide metabolites in water: alachlor ethanesulfonic acid (ESA); alachlor oxanilic acid; acetochlor ESA; acetochlor oxanilic acid; metolachlor ESA; and metolachlor oxanilic acid. Good precision and accuracy were demonstrated for both the HPLC-DAD and HPLC/MS methods in reagent water, surface water, and ground water. The average HPLC-DAD recoveries of the chloroacetanilide herbicide metabolites from water samples spiked at 0.25, 0.5 and 2.0 μg/l ranged from 84 to 112%, with relative standard deviations of 18% or less. The average HPLC/MS recoveries of the metabolites from water samples spiked at 0.05, 0.2 and 2.0 μg/l ranged from 81 to 118%, with relative standard deviations of 20% or less. The limit of quantitation (LOQ) for all metabolites using the HPLC-DAD method was 0.20 μg/l, whereas the LOQ using the HPLC/MS method was at 0.05 μg/l. These metabolite-determination methods are valuable for acquiring information about water quality and the fate and transport of the parent chloroacetanilide herbicides in water.</p></div></div></div>","language":"English","publisher":"Elsevier","doi":"10.1016/S0048-9697(99)00538-0","issn":"00489697","usgsCitation":"Hostetler, K., and Thurman, E., 2000, Determination of chloroacetanilide herbicide metabolites in water using high-performance liquid chromatography-diode array detection and high-performance liquid chromatography/mass spectrometry: Science of the Total Environment, v. 248, no. 2-3, p. 147-155, https://doi.org/10.1016/S0048-9697(99)00538-0.","productDescription":"9 p.","startPage":"147","endPage":"155","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233828,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208229,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0048-9697(99)00538-0"}],"volume":"248","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ff9ee4b0c8380cd4f2b5","contributors":{"authors":[{"text":"Hostetler, K.A.","contributorId":29855,"corporation":false,"usgs":true,"family":"Hostetler","given":"K.A.","email":"","affiliations":[],"preferred":false,"id":395000,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":395001,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022588,"text":"70022588 - 2000 - Dating young groundwater with sulfur hexafluoride: Natural and anthropogenic sources of sulfur hexafluoride","interactions":[],"lastModifiedDate":"2018-12-07T06:25:39","indexId":"70022588","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Dating young groundwater with sulfur hexafluoride: Natural and anthropogenic sources of sulfur hexafluoride","docAbstract":"<p><span>Sulfur hexafluoride (SF</span><sub>6</sub><span>) is primarily of anthropogenic origin but also occurs naturally. The troposphere concentration of SF</span><sub>6</sub><span><span>&nbsp;</span>has increased from a steady state value of 0.054±0.009 to more than 4 parts per trillion volume during the past 40 years. An analytical procedure was developed for measuring concentrations of SF</span><sub>6</sub><span><span>&nbsp;</span>to less than 0.01 fmol/L in water. Groundwater can be dated with SF</span><sub>6</sub><span><span>&nbsp;</span>if it is in equilibrium with atmospheric SF</span><sub>6</sub><span><span>&nbsp;</span>at the time of recharge and does not contain significant SF</span><sub>6</sub><span><span>&nbsp;</span>from other sources. The dating range of SF</span><sub>6</sub><span><span>&nbsp;</span>is currently 0 to 30 years. The tracer was successfully used to date shallow groundwater of the Atlantic Coastal Plain sand aquifers of the United States and springs issuing near the top of the Blue Ridge Mountains of Virginia. Significant concentrations of naturally occurring SF</span><sub>6</sub><span><span>&nbsp;</span>were found in some igneous, volcanic, and sedimentary rocks and in some hydrothermal fluids.</span></p>","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000WR900151","usgsCitation":"Busenberg, E., and Plummer, N., 2000, Dating young groundwater with sulfur hexafluoride: Natural and anthropogenic sources of sulfur hexafluoride: Water Resources Research, v. 36, no. 10, p. 3011-3030, https://doi.org/10.1029/2000WR900151.","productDescription":"20 p.","startPage":"3011","endPage":"3030","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":487378,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000wr900151","text":"Publisher Index Page"},{"id":230471,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fde4e4b0c8380cd4e9d5","contributors":{"authors":[{"text":"Busenberg, Eurybiades ebusenbe@usgs.gov","contributorId":2271,"corporation":false,"usgs":true,"family":"Busenberg","given":"Eurybiades","email":"ebusenbe@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":394167,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Plummer, Niel 0000-0002-4020-1013 nplummer@usgs.gov","orcid":"https://orcid.org/0000-0002-4020-1013","contributorId":190100,"corporation":false,"usgs":true,"family":"Plummer","given":"Niel","email":"nplummer@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":394168,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70022040,"text":"70022040 - 2000 - Bioavailability of particle-associated Se to the bivalve Potamocorbula amurensis","interactions":[],"lastModifiedDate":"2018-12-03T10:46:00","indexId":"70022040","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Bioavailability of particle-associated Se to the bivalve Potamocorbula amurensis","docAbstract":"<div class=\"hlFld-Abstract\"><div id=\"abstractBox\"><p class=\"articleBody_abstractText\">Elemental selenium, Se(0), is a prevalent chemical form in sediments, but little is known about its bioavailability. We evaluated the bioavailability of two forms of Se(0) by generating radioisotopic<span>&nbsp;</span><sup>75</sup>Se(0) through bacterial dissimilatory reduction of<span>&nbsp;</span><sup>75</sup>SeO<sub>3</sub><sup>2</sup><sup>-</sup><span>&nbsp;</span>by pure bacterial cultures (SES) and by an anaerobic sediment microbial consortium (SED). A third form was generated by reducing<span>&nbsp;</span><sup>75</sup>SeO<sub>3</sub><sup>2</sup><sup>-</sup><span>&nbsp;</span>with ascorbic acid (AA). Speciation determinations showed that AA and SES were &gt;90% Se(0), but SED showed a mixture of Se(0), selenoanions, and a residual fraction. Pulse-chase techniques were used to measure assimilation efficiencies (AE) of these particulate Se forms by the bivalve<span>&nbsp;</span><i>Potamocorbula amurensis</i>. Mean AE values were 3 ± 2% for AA, 7 ± 1% for SES, and 28 ± 15% for SED, showing that the bioavailability of reduced, particle-associated Se is dependent upon its origin. To determine if oxidative microbial processes increased Se transfer, SES<span>&nbsp;</span><sup>75</sup>Se(0) was incubated with an aerobic sediment microbial consortium. After 113 d of incubation, 36% of SES Se(0) was oxidized to SeO<sub>3</sub><sup>2</sup><sup>-</sup>. Assimilation of total particulate Se was unaffected however (mean AE = 5.5%). The mean AE from the diatom<span>&nbsp;</span><i>Phaeodactylum tricornutum</i><span>&nbsp;</span>was 58 ± 8%, verifying the importance of Se associated with biogenic particles. Speciation and AE results from SED suggest that selenoanion reduction in wetlands and estuaries produces biologically available reduced selenium.</p></div></div>","language":"English","publisher":"ACS","doi":"10.1021/es001013f","issn":"0013936X","usgsCitation":"Schlekat, C., Dowdle, P., Lee, B., Luoma, S., and Oremland, R., 2000, Bioavailability of particle-associated Se to the bivalve Potamocorbula amurensis: Environmental Science & Technology, v. 34, no. 21, p. 4504-4510, https://doi.org/10.1021/es001013f.","productDescription":"7 p.","startPage":"4504","endPage":"4510","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230474,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206654,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es001013f"}],"volume":"34","issue":"21","noUsgsAuthors":false,"publicationDate":"2000-09-16","publicationStatus":"PW","scienceBaseUri":"5059f13ee4b0c8380cd4ab0d","contributors":{"authors":[{"text":"Schlekat, C.E.","contributorId":89683,"corporation":false,"usgs":true,"family":"Schlekat","given":"C.E.","email":"","affiliations":[],"preferred":false,"id":392128,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dowdle, P.R.","contributorId":77678,"corporation":false,"usgs":true,"family":"Dowdle","given":"P.R.","email":"","affiliations":[],"preferred":false,"id":392126,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lee, B.-G.","contributorId":11777,"corporation":false,"usgs":true,"family":"Lee","given":"B.-G.","email":"","affiliations":[],"preferred":false,"id":392125,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":392127,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Oremland, R.S.","contributorId":97512,"corporation":false,"usgs":true,"family":"Oremland","given":"R.S.","email":"","affiliations":[],"preferred":false,"id":392129,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}}
]}