No abstract avaikable
","largerWorkType":{"id":24,"text":"Conference Paper"},"largerWorkTitle":"Proceedings of the third federal interagency hydrologic modeling conference","conferenceTitle":"Third federal interagency hydrologic modeling conference","conferenceLocation":"Reno, NV","language":"English","usgsCitation":"Johnson, H., Jacobson, R., and DeLonay, A., 2006, Hydroecological modeling of the Lower Missouri River, in Proceedings of the third federal interagency hydrologic modeling conference, Reno, NV, p. 1-8.","productDescription":"8 p.","startPage":"1","endPage":"8","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"links":[{"id":326848,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"57b6dc66e4b03fd6b7d94c50","contributors":{"authors":[{"text":"Johnson, H.E.","contributorId":56757,"corporation":false,"usgs":true,"family":"Johnson","given":"H.E.","email":"","affiliations":[],"preferred":false,"id":646220,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jacobson, R. B. 0000-0002-8368-2064","orcid":"https://orcid.org/0000-0002-8368-2064","contributorId":92614,"corporation":false,"usgs":true,"family":"Jacobson","given":"R. B.","affiliations":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"preferred":true,"id":646221,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"DeLonay, A. J. 0000-0002-3752-2799","orcid":"https://orcid.org/0000-0002-3752-2799","contributorId":34246,"corporation":false,"usgs":true,"family":"DeLonay","given":"A. J.","affiliations":[],"preferred":false,"id":646222,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1003370,"text":"1003370 - 2006 - Variability and regulation of denitrification in an Upper Mississippi River backwater","interactions":[],"lastModifiedDate":"2012-02-02T00:15:43","indexId":"1003370","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2564,"text":"Journal of the North American Benthological Society","onlineIssn":"1937-237X","printIssn":"0887-3593","active":true,"publicationSubtype":{"id":10}},"title":"Variability and regulation of denitrification in an Upper Mississippi River backwater","docAbstract":"Sediments in the backwaters of the Upper Mississippi River (UMR) are highly organic and provide an optimal environment for N removal. We monitored an 8.6-ha UMR backwater site near La Crosse, Wisconsin, for nearly 3 y to assess temporal variability, seasonal trends, and the factors regulating denitrification. We measured rates of unamended denitrification (DEN) and denitrification enzyme activity (DEA) rates at ambient temperature and DEA at 30 degrees C (DEA30). Seasonal mean (+/- 1 SE) DEN rates ranged from 0.041 +/- 0.015 to 0.47 +/- 0.23 mu g N cm(-2) h(-1)and were highest in winter and lowest in autumn. Seasonal rates of DEA exhibited a different pattern with the highest rates in summer (25.6 +/- 3.4 mu g N cm(-2) h(-1)) and the lowest rates in winter (10.6 +/- 2.1 mu g N cm(-2) h(-1)). The overall mean DEA30 rate was 31.0 +/- 1.9 mu g N cm(-2) h(-1) but showed no significant seasonal pattern. Short-term (weekly) and seasonal variability exhibited by rates of DEN and DEA were best explained by water-column NO3- concentration and temperature, respectively. No environmental variables explained a significant amount of variability in DEA30. Our results suggest that nutrient (i.e., NO3-) availability and temperature are both regulators of denitrification, with NO3- concentration being the most important limiting factor in this system. The high DEN rates during winter were in response to elevated NO3- concentrations resulting from a chain reaction beginning with algal blooms creating oxic conditions that stimulated nitrification. Increasing hydrological connectivity in large rivers as a river management tool to reduce N flux to downstream areas may be beneficial.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of the North American Benthological Society","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"North Amererican Benthological Society","publisherLocation":"Lawrence, KS","usgsCitation":"Strauss, E., Richardson, W.B., Cavanaugh, J., Bartsch, L., Kreiling, R., and Standorf, A., 2006, Variability and regulation of denitrification in an Upper Mississippi River backwater: Journal of the North American Benthological Society, v. 25, no. 3, p. 596-606.","productDescription":"pp. 596-606","startPage":"596","endPage":"606","numberOfPages":"11","costCenters":[{"id":606,"text":"Upper Midwest Environmental Sciences Center","active":true,"usgs":true}],"links":[{"id":200056,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a14e4b07f02db602c53","contributors":{"authors":[{"text":"Strauss, E.A.","contributorId":26010,"corporation":false,"usgs":true,"family":"Strauss","given":"E.A.","email":"","affiliations":[],"preferred":false,"id":313187,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Richardson, W. B.","contributorId":16363,"corporation":false,"usgs":true,"family":"Richardson","given":"W.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":313185,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cavanaugh, J.C.","contributorId":25269,"corporation":false,"usgs":true,"family":"Cavanaugh","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":313186,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bartsch, L.A.","contributorId":7675,"corporation":false,"usgs":true,"family":"Bartsch","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":313184,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kreiling, Rebecca M. 0000-0002-9295-4156","orcid":"https://orcid.org/0000-0002-9295-4156","contributorId":33429,"corporation":false,"usgs":true,"family":"Kreiling","given":"Rebecca M.","affiliations":[],"preferred":false,"id":313188,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Standorf, A.J.","contributorId":78847,"corporation":false,"usgs":true,"family":"Standorf","given":"A.J.","email":"","affiliations":[],"preferred":false,"id":313189,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":1001059,"text":"1001059 - 2006 - Forecasting effects of climate change on Great Lakes fisheries: models that link habitat supply to population dynamics can help","interactions":[],"lastModifiedDate":"2016-05-09T09:13:01","indexId":"1001059","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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}},"title":"Forecasting effects of climate change on Great Lakes fisheries: models that link habitat supply to population dynamics can help","docAbstract":"Future changes to climate in the Great Lakes may have important consequences for fisheries. Evidence suggests that Great Lakes air and water temperatures have risen and the duration of ice cover has lessened during the past century. Global circulation models (GCMs) suggest future warming and increases in precipitation in the region. We present new evidence that water temperatures have risen in Lake Erie, particularly during summer and winter in the period 19652000. GCM forecasts coupled with physical models suggest lower annual runoff, less ice cover, and lower lake levels in the future, but the certainty of these forecasts is low. Assessment of the likely effects of climate change on fish stocks will require an integrative approach that considers several components of habitat rather than water temperature alone. We recommend using mechanistic models that couple habitat conditions to population demographics to explore integrated effects of climate-caused habitat change and illustrate this approach with a model for Lake Erie walleye (Sander vitreum). We show that the combined effect on walleye populations of plausible changes in temperature, river hydrology, lake levels, and light penetration can be quite different from that which would be expected based on consideration of only a single factor.
","language":"English","publisher":"NRC Research Press","doi":"10.1139/f05-239","usgsCitation":"Jones, M., Shuter, B.J., Zhao, Y., and Stockwell, J.D., 2006, Forecasting effects of climate change on Great Lakes fisheries: models that link habitat supply to population dynamics can help: Canadian Journal of Fisheries and Aquatic Sciences, v. 63, no. 2, p. 457-468, https://doi.org/10.1139/f05-239.","productDescription":"12 p.","startPage":"457","endPage":"468","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":133279,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"63","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b24e4b07f02db6ae519","contributors":{"authors":[{"text":"Jones, Michael L.","contributorId":7219,"corporation":false,"usgs":false,"family":"Jones","given":"Michael L.","affiliations":[{"id":6590,"text":"Department of Fisheries and Wildlife, Michigan State University","active":true,"usgs":false}],"preferred":false,"id":310364,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shuter, Brian J.","contributorId":29372,"corporation":false,"usgs":true,"family":"Shuter","given":"Brian","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":310365,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Zhao, Yingming","contributorId":49752,"corporation":false,"usgs":true,"family":"Zhao","given":"Yingming","affiliations":[],"preferred":false,"id":310366,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Stockwell, Jason D. 0000-0003-3393-6799","orcid":"https://orcid.org/0000-0003-3393-6799","contributorId":61004,"corporation":false,"usgs":false,"family":"Stockwell","given":"Jason","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":310367,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":1001072,"text":"1001072 - 2006 - Modeling wetland plant community response to assess water-level regulation scenarios in the Lake Ontario-St. Lawrence River basin","interactions":[],"lastModifiedDate":"2016-05-09T10:45:38","indexId":"1001072","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1552,"text":"Environmental Monitoring and Assessment","onlineIssn":"1573-2959","printIssn":"0167-6369","active":true,"publicationSubtype":{"id":10}},"title":"Modeling wetland plant community response to assess water-level regulation scenarios in the Lake Ontario-St. Lawrence River basin","docAbstract":"The International Joint Commission has recently completed a five-year study (2000-2005) to review the operation of structures controlling the flows and levels of the Lake Ontario - St. Lawrence River system. In addition to addressing the multitude of stakeholder interests, the regulation plan review also considers environmental sustainability and integrity of wetlands and various ecosystem components. The present paper outlines the general approach, scientific methodology and applied management considerations of studies quantifying the relationships between hydrology and wetland plant assemblages (% occurrence, surface area) in Lake Ontario and the Upper and Lower St. Lawrence River. Although similar study designs were used across the study region, different methodologies were required that were specifically adapted to suit the important regional differences between the lake and river systems, range in water-level variations, and confounding factors (geomorphic types, exposure, sediment characteristics, downstream gradient of water quality, origin of water masses in the Lower River). Performance indicators (metrics), such as total area of wetland in meadow marsh vegetation type, that link wetland response to water levels will be used to assess the effects of different regulation plans under current and future (climate change) water-supply scenarios.
","language":"English","publisher":"Springer","doi":"10.1007/s10661-005-9086-4","usgsCitation":"Hudon, C., Wilcox, D., and Ingram, J., 2006, Modeling wetland plant community response to assess water-level regulation scenarios in the Lake Ontario-St. Lawrence River basin: Environmental Monitoring and Assessment, v. 113, no. 1-3, p. 303-328, https://doi.org/10.1007/s10661-005-9086-4.","productDescription":"26 p.","startPage":"303","endPage":"328","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":477564,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://hdl.handle.net/20.500.12648/2305","text":"External Repository"},{"id":133564,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"113","issue":"1-3","noUsgsAuthors":false,"publicationDate":"2006-02-24","publicationStatus":"PW","scienceBaseUri":"4f4e4b05e4b07f02db69976f","contributors":{"authors":[{"text":"Hudon, Christiane","contributorId":80632,"corporation":false,"usgs":true,"family":"Hudon","given":"Christiane","email":"","affiliations":[],"preferred":false,"id":310395,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wilcox, Douglas","contributorId":72764,"corporation":false,"usgs":true,"family":"Wilcox","given":"Douglas","affiliations":[],"preferred":false,"id":310394,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ingram, Joel","contributorId":65046,"corporation":false,"usgs":true,"family":"Ingram","given":"Joel","affiliations":[],"preferred":false,"id":310393,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1001073,"text":"1001073 - 2006 - Predicting crappie recruitment in Ohio reservoirs with spawning stock size, larval density, and chlorophyll concentrations","interactions":[],"lastModifiedDate":"2012-02-02T00:04:44","indexId":"1001073","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2886,"text":"North American Journal of Fisheries Management","active":true,"publicationSubtype":{"id":10}},"title":"Predicting crappie recruitment in Ohio reservoirs with spawning stock size, larval density, and chlorophyll concentrations","docAbstract":"Stock-recruit models typically use only spawning stock size as a predictor of recruitment to a fishery. In this paper, however, we used spawning stock size as well as larval density and key environmental variables to predict recruitment of white crappies Pomoxis annularis and black crappies P. nigromaculatus, a genus notorious for variable recruitment. We sampled adults and recruits from 11 Ohio reservoirs and larvae from 9 reservoirs during 1998-2001. We sampled chlorophyll as an index of reservoir productivity and obtained daily estimates of water elevation to determine the impact of hydrology on recruitment. Akaike's information criterion (AIC) revealed that Ricker and Beverton-Holt stock-recruit models that included chlorophyll best explained the variation in larval density and age-2 recruits. Specifically, spawning stock catch per effort (CPE) and chlorophyll explained 63-64% of the variation in larval density. In turn, larval density and chlorophyll explained 43-49% of the variation in age-2 recruit CPE. Finally, spawning stock CPE and chlorophyll were the best predictors of recruit CPE (i.e., 74-86%). Although larval density and recruitment increased with chlorophyll, neither was related to seasonal water elevation. Also, the AIC generally did not distinguish between Ricker and Beverton-Holt models. From these relationships, we concluded that crappie recruitment can be limited by spawning stock CPE and larval production when spawning stock sizes are low (i.e., CPE , 5 crappies/net-night). At higher levels of spawning stock sizes, spawning stock CPE and recruitment were less clearly related. To predict recruitment in Ohio reservoirs, managers should assess spawning stock CPE with trap nets and estimate chlorophyll concentrations. To increase crappie recruitment in reservoirs where recruitment is consistently poor, managers should use regulations to increase spawning stock size, which, in turn, should increase larval production and recruits to the fishery.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"North American Journal of Fisheries Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","usgsCitation":"Bunnell, D., Hale, R.S., Vanni, M., and Stein, R., 2006, Predicting crappie recruitment in Ohio reservoirs with spawning stock size, larval density, and chlorophyll concentrations: North American Journal of Fisheries Management, v. 26, no. 1, p. 1-12.","productDescription":"p. 1-12","startPage":"1","endPage":"12","numberOfPages":"11","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":133662,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"26","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4aafe4b07f02db66cae6","contributors":{"authors":[{"text":"Bunnell, David B.","contributorId":14360,"corporation":false,"usgs":true,"family":"Bunnell","given":"David B.","affiliations":[],"preferred":false,"id":310396,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hale, R. Scott","contributorId":104868,"corporation":false,"usgs":true,"family":"Hale","given":"R.","email":"","middleInitial":"Scott","affiliations":[],"preferred":false,"id":310399,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Vanni, Michael J.","contributorId":49756,"corporation":false,"usgs":true,"family":"Vanni","given":"Michael J.","affiliations":[],"preferred":false,"id":310398,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Stein, Roy A.","contributorId":21494,"corporation":false,"usgs":true,"family":"Stein","given":"Roy A.","affiliations":[],"preferred":false,"id":310397,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":1001079,"text":"1001079 - 2006 - A water-budget approach to restoring a sedge fen affected by diking and ditching","interactions":[],"lastModifiedDate":"2013-01-29T10:24:26","indexId":"1001079","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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":"A water-budget approach to restoring a sedge fen affected by diking and ditching","docAbstract":"A vast, ground-water-supported sedge fen in the Upper Peninsula of Michigan, USA was ditched in the early 1900s in a failed attempt to promote agriculture. Dikes were later constructed to impound seasonal sheet surface flows for waterfowl management. The US Fish and Wildlife Service, which now manages the wetland as part of Seney National Wildlife Refuge, sought to redirect water flows from impounded C-3 Pool to reduce erosion in downstream Walsh Ditch, reduce ground-water losses into the ditch, and restore sheet flows of surface water to the peatland. A water budget was developed for C-3 Pool, which serves as the central receiving and distribution body for water in the affected wetland. Surface-water inflows and outflows were measured in associated ditches and natural creeks, ground-water flows were estimated using a network of wells and piezometers, and precipitation and evaporation/evapotranspiration components were estimated using local meteorological data. Water budgets for the 1999 springtime peak flow period and the 1999 water year were used to estimate required releases of water from C-3 Pool via outlets other than Walsh Ditch and to guide other restoration activities. Refuge managers subsequently used these results to guide restoration efforts, including construction of earthen dams in Walsh Ditch upslope from the pool to stop surface flow, installation of new water-control structures to redirect surface water to sheet flow and natural creek channels, planning seasonal releases from C-3 Pool to avoid erosion in natural channels, stopping flow in downslope Walsh Ditch to reduce erosion, and using constructed earthen dams and natural beaver dams to flood the ditch channel below C-3 Pool. Interactions between ground water and surface water are critical for maintaining ecosystem processes in many wetlands, and management actions directed at restoring either ground- or surface-water flow patterns often affect both of these components of the water budget. This approach could thus prove useful in guiding restoration efforts in many hydrologically altered and managed wetlands worldwide.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.jhydrol.2005.07.026","usgsCitation":"Wilcox, D.A., Sweat, M.J., Carlson, M.L., and Kowalski, K., 2006, A water-budget approach to restoring a sedge fen affected by diking and ditching: Journal of Hydrology, v. 320, no. 3-4, p. 501-517, https://doi.org/10.1016/j.jhydrol.2005.07.026.","productDescription":"p. 501-517","startPage":"501","endPage":"517","numberOfPages":"16","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":477565,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://hdl.handle.net/20.500.12648/2319","text":"External Repository"},{"id":133703,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266667,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jhydrol.2005.07.026"}],"volume":"320","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b16e4b07f02db6a51de","contributors":{"authors":[{"text":"Wilcox, Douglas A.","contributorId":36880,"corporation":false,"usgs":true,"family":"Wilcox","given":"Douglas","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":310417,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sweat, Michael J. mjsweat@usgs.gov","contributorId":356,"corporation":false,"usgs":true,"family":"Sweat","given":"Michael","email":"mjsweat@usgs.gov","middleInitial":"J.","affiliations":[{"id":5050,"text":"WY-MT Water Science Center","active":true,"usgs":true}],"preferred":true,"id":310415,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Carlson, Martha L.","contributorId":50869,"corporation":false,"usgs":true,"family":"Carlson","given":"Martha","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":310418,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kowalski, Kurt P. 0000-0002-8424-4701 kkowalski@usgs.gov","orcid":"https://orcid.org/0000-0002-8424-4701","contributorId":3768,"corporation":false,"usgs":true,"family":"Kowalski","given":"Kurt P.","email":"kkowalski@usgs.gov","affiliations":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"preferred":true,"id":310416,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70028440,"text":"70028440 - 2006 - Increasing streamflow and baseflow in Mississippi River since the 1940 s: Effect of land use change","interactions":[],"lastModifiedDate":"2012-03-12T17:20:54","indexId":"70028440","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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":"Increasing streamflow and baseflow in Mississippi River since the 1940 s: Effect of land use change","docAbstract":"A trend of increasing streamflow has been observed in the Mississippi River (MR) basin since the 1940 s as a result of increased precipitation. Herein we show that increasing MR flow is mainly in its baseflow as a result of land use change and accompanying agricultural activities that occurred in the MR basin during the last 60 years. Agricultural land use change in the MR basin has affected the basin-scale hydrology: more precipitation is being routed into streams as baseflow than stormflow since 1940 s. We explain that the conversion of perennial vegetation to seasonal row crops, especially soybeans, in the basin since 1940 s may have reduced evapotranspiration, increased groundwater recharge, and thus increased baseflow and streamflow. This explanation is supported with a data analysis of the annually and monthly flow rates at various river stations in the MR basin. Results from this study will help to direct our effort in managing land use and in reducing nutrient levels in MR and other major rivers since nutrient concentrations and loads carried by storm water and baseflow are different. ?? 2005 Elsevier B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.jhydrol.2005.09.033","issn":"00221694","usgsCitation":"Zhang, Y., and Schilling, K.E., 2006, Increasing streamflow and baseflow in Mississippi River since the 1940 s: Effect of land use change: Journal of Hydrology, v. 324, no. 1-4, p. 412-422, https://doi.org/10.1016/j.jhydrol.2005.09.033.","startPage":"412","endPage":"422","numberOfPages":"11","costCenters":[],"links":[{"id":210300,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jhydrol.2005.09.033"},{"id":237178,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"324","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3a07e4b0c8380cd61b12","contributors":{"authors":[{"text":"Zhang, Y.-K.","contributorId":44309,"corporation":false,"usgs":true,"family":"Zhang","given":"Y.-K.","email":"","affiliations":[],"preferred":false,"id":418056,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schilling, K. E.","contributorId":61982,"corporation":false,"usgs":true,"family":"Schilling","given":"K.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":418057,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70028439,"text":"70028439 - 2006 - Use of borehole radar reflection logging to monitor steam-enhanced remediation in fractured limestone--Results of numerical modelling and a field experiment","interactions":[],"lastModifiedDate":"2019-10-16T18:10:19","indexId":"70028439","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2165,"text":"Journal of Applied Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"Use of borehole radar reflection logging to monitor steam-enhanced remediation in fractured limestone--Results of numerical modelling and a field experiment","docAbstract":"Ground penetrating radar is an efficient geophysical method for the detection and location of fractures and fracture zones in electrically resistive rocks. In this study, the use of down-hole (borehole) radar reflection logs to monitor the injection of steam in fractured rocks was tested as part of a field-scale, steam-enhanced remediation pilot study conducted at a fractured limestone quarry contaminated with chlorinated hydrocarbons at the former Loring Air Force Base, Limestone, Maine, USA. In support of the pilot study, borehole radar reflection logs were collected three times (before, during, and near the end of steam injection) using broadband 100 MHz electric dipole antennas. Numerical modelling was performed to predict the effect of heating on radar-frequency electromagnetic (EM) wave velocity, attenuation, and fracture reflectivity. The modelling results indicate that EM wave velocity and attenuation change substantially if heating increases the electrical conductivity of the limestone matrix. Furthermore, the net effect of heat-induced variations in fracture-fluid dielectric properties on average medium velocity is insignificant because the expected total fracture porosity is low. In contrast, changes in fracture fluid electrical conductivity can have a significant effect on EM wave attenuation and fracture reflectivity. Total replacement of water by steam in a fracture decreases fracture reflectivity of a factor of 10 and induces a change in reflected wave polarity. Based on the numerical modelling results, a reflection amplitude analysis method was developed to delineate fractures where steam has displaced water. Radar reflection logs collected during the three acquisition periods were analysed in the frequency domain to determine if steam had replaced water in the fractures (after normalizing the logs to compensate for differences in antenna performance between logging runs). Analysis of the radar reflection logs from a borehole where the temperature increased substantially during the steam injection experiment shows an increase in attenuation and a decrease in reflectivity in the vicinity of the borehole. Results of applying the reflection amplitude analysis method developed for this study indicate that steam did not totally replace the water in most of the fractures. The observed decreases in reflectivity were consistent with an increase in fracture-water temperature, rather than the presence of steam. A limiting assumption of the reflection amplitude analysis method is the requirement for complete displacement of water in a fracture by steam.
","language":"English","publisher":"Elsevier","doi":"10.1016/j.jappgeo.2005.12.006","issn":"09269851","usgsCitation":"Gregoire, C., Joesten, P., and Lane, J., 2006, Use of borehole radar reflection logging to monitor steam-enhanced remediation in fractured limestone--Results of numerical modelling and a field experiment: Journal of Applied Geophysics, v. 60, no. 1, p. 41-54, https://doi.org/10.1016/j.jappgeo.2005.12.006.","productDescription":"14 p.","startPage":"41","endPage":"54","costCenters":[{"id":493,"text":"Office of Ground Water","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":237177,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Maine","city":"Limestone","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -67.92117118835449,\n 46.95465637620638\n ],\n [\n -67.91112899780273,\n 46.95465637620638\n ],\n [\n -67.91112899780273,\n 46.96022176137895\n ],\n [\n -67.92117118835449,\n 46.96022176137895\n ],\n [\n -67.92117118835449,\n 46.95465637620638\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"60","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bbec7e4b08c986b3297a7","contributors":{"authors":[{"text":"Gregoire, C.","contributorId":37142,"corporation":false,"usgs":true,"family":"Gregoire","given":"C.","email":"","affiliations":[],"preferred":false,"id":418053,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Joesten, P. K.","contributorId":62818,"corporation":false,"usgs":true,"family":"Joesten","given":"P. K.","affiliations":[],"preferred":false,"id":418054,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lane, J.W. Jr.","contributorId":66723,"corporation":false,"usgs":true,"family":"Lane","given":"J.W.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":418055,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030304,"text":"70030304 - 2006 - Measuring groundwater-surface water interaction and its effect on wetland stream benthic productivity, Trout Lake watershed, northern Wisconsin, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:21:02","indexId":"70030304","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Measuring groundwater-surface water interaction and its effect on wetland stream benthic productivity, Trout Lake watershed, northern Wisconsin, USA","docAbstract":"Measurements of groundwater-surface water exchange at three wetland stream sites were related to patterns in benthic productivity as part of the US Geological Survey's Northern Temperate Lakes-Water, Energy and Biogeochemical Budgets (NTL-WEBB) project. The three sites included one high groundwater discharge (HGD) site, one weak groundwater discharge (WGD) site, and one groundwater recharge (GR) site. Large upward vertical gradients at the HGD site were associated with smallest variation in head below the stream and fewest gradient reversals between the stream and the groundwater beneath the stream, and the stream and the adjacent streambank. The WGD site had the highest number of gradient reversals reflecting the average condition being closest to zero vertical gradient. The duration of groundwater discharge events was related to the amount of discharge, where the HGD site had the longest strong-gradient durations for both horizontal and vertical groundwater flow. Strong groundwater discharge also controlled transient temperature and chemical hyporheic conditions by limiting the infiltration of surface water. Groundwater-surface water interactions were related to highly significant patterns in benthic invertebrate abundance, taxonomic richness, and periphyton respiration. The HGD site abundance was 35% greater than in the WGD site and 53% greater than the GR site; richness and periphyton respiration were also significantly greater (p???0.001, 31 and 44%, respectively) in the HGD site than in the GR site. The WGD site had greater abundance (27%), richness (19%) and periphyton respiration (39%) than the GR site. This work suggests groundwater-surface water interactions can strongly influence benthic productivity, thus emphasizing the importance of quantitative hydrology for management of wetland-stream ecosystems in the northern temperate regions. ?? 2005 Elsevier B.V. All rights reserved.","largerWorkTitle":"Journal of Hydrology","language":"English","doi":"10.1016/j.jhydrol.2005.07.029","issn":"00221694","usgsCitation":"Hunt, R.J., Strand, M., and Walker, J., 2006, Measuring groundwater-surface water interaction and its effect on wetland stream benthic productivity, Trout Lake watershed, northern Wisconsin, USA, in Journal of Hydrology, v. 320, no. 3-4, p. 370-384, https://doi.org/10.1016/j.jhydrol.2005.07.029.","startPage":"370","endPage":"384","numberOfPages":"15","costCenters":[],"links":[{"id":211775,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jhydrol.2005.07.029"},{"id":239128,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"320","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a534ae4b0c8380cd6c99a","contributors":{"authors":[{"text":"Hunt, R. J.","contributorId":40164,"corporation":false,"usgs":true,"family":"Hunt","given":"R.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":426589,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Strand, M.","contributorId":91299,"corporation":false,"usgs":true,"family":"Strand","given":"M.","email":"","affiliations":[],"preferred":false,"id":426591,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Walker, J.F.","contributorId":86743,"corporation":false,"usgs":true,"family":"Walker","given":"J.F.","email":"","affiliations":[],"preferred":false,"id":426590,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030999,"text":"70030999 - 2006 - Sulfate deposition in subsurface regolith in Gusev crater, Mars","interactions":[],"lastModifiedDate":"2018-11-28T09:04:37","indexId":"70030999","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2317,"text":"Journal of Geophysical Research E: Planets","active":true,"publicationSubtype":{"id":10}},"title":"Sulfate deposition in subsurface regolith in Gusev crater, Mars","docAbstract":"Excavating into the shallow Martian subsurface has the potential to expose stratigraphic layers and mature regolith, which may hold a record of more ancient aqueous interactions than those expected under current Martian surface conditions. During the Spirit rover's exploration of Gusev crater, rover wheels were used to dig three trenches into the subsurface regolith down to 6-11 cm depth: Road Cut, the Big Hole, and The Boroughs. A high oxidation state of Fe and high concentrations of Mg, S, Cl, and Br were found in the subsurface regolith within the two trenches on the plains, between the Bonneville crater and the foot of Columbia Hills. Data analyses on the basis of geochemistry and mineralogy observations suggest the deposition of sulfate minerals within the subsurface regolith, mainly Mg-sulfates accompanied by minor Ca-sulfates and perhaps Fe-sulfates. An increase of Fe2O3, an excess of SiO2, and a minor decrease in the olivine proportion relative to surface materials are also inferred. Three hypotheses are proposed to explain the geochemical trends observed in trenches: (1) multiple episodes of acidic fluid infiltration, accompanied by in situ interaction with igneous minerals and salt deposition; (2) an open hydrologic system characterized by ion transportation in the fluid, subsequent evaporation of the fluid, and salt deposition; and (3) emplacement and mixing of impact ejecta of variable composition. While all three may have plausibly contributed to the current state of the subsurface regolith, the geochemical data are most consistent with ion transportation by fluids and salt deposition as a result of open-system hydrologic behavior. Although sulfates make up >20 wt.% of the regolith in the wall of The Boroughs trench, a higher hydrated sulfate than kieserite within The Boroughs or a greater abundance of sulfates elsewhere than is seen in The Boroughs wall regolith would be needed to hold the structural water indicated by the water-equivalent hydrogen concentration observed by the Gamma-Ray Spectrometer on Odyssey in the Gusev region.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Geophysical Research E: Planets","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Geophysical Union","publisherLocation":"Washington, D.C.","doi":"10.1029/2005JE002513","issn":"01480227","usgsCitation":"Wang, A., Haskin, L., Squyres, S.W., Jolliff, B., Crumpler, L., Gellert, R., Schroder, C., Herkenhoff, K.E., Hurowitz, J., Tosca, N., Farrand, W.H., Anderson, R., and Knudson, A., 2006, Sulfate deposition in subsurface regolith in Gusev crater, Mars: Journal of Geophysical Research E: Planets, v. 111, no. E2, 19 p., https://doi.org/10.1029/2005JE002513.","productDescription":"19 p.","costCenters":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"links":[{"id":477418,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2005je002513","text":"Publisher Index Page"},{"id":238641,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Gusev crater; Mars","volume":"111","issue":"E2","noUsgsAuthors":false,"publicationDate":"2006-02-21","publicationStatus":"PW","scienceBaseUri":"505b9dc0e4b08c986b31da54","contributors":{"authors":[{"text":"Wang, A.","contributorId":46735,"corporation":false,"usgs":true,"family":"Wang","given":"A.","email":"","affiliations":[],"preferred":false,"id":429578,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Haskin, L.A.","contributorId":74926,"corporation":false,"usgs":true,"family":"Haskin","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":429582,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Squyres, S. W.","contributorId":31836,"corporation":false,"usgs":true,"family":"Squyres","given":"S.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":429576,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Jolliff, B.L.","contributorId":21268,"corporation":false,"usgs":true,"family":"Jolliff","given":"B.L.","email":"","affiliations":[],"preferred":false,"id":429575,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Crumpler, L.","contributorId":59545,"corporation":false,"usgs":true,"family":"Crumpler","given":"L.","email":"","affiliations":[],"preferred":false,"id":429579,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Gellert, Ralf","contributorId":35049,"corporation":false,"usgs":false,"family":"Gellert","given":"Ralf","email":"","affiliations":[{"id":12660,"text":"University of Guelph","active":true,"usgs":false}],"preferred":false,"id":429577,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Schroder, C.","contributorId":67201,"corporation":false,"usgs":true,"family":"Schroder","given":"C.","affiliations":[],"preferred":false,"id":429581,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Herkenhoff, Kenneth E. 0000-0002-3153-6663 kherkenhoff@usgs.gov","orcid":"https://orcid.org/0000-0002-3153-6663","contributorId":2275,"corporation":false,"usgs":true,"family":"Herkenhoff","given":"Kenneth","email":"kherkenhoff@usgs.gov","middleInitial":"E.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":429572,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Hurowitz, J.","contributorId":17742,"corporation":false,"usgs":true,"family":"Hurowitz","given":"J.","email":"","affiliations":[],"preferred":false,"id":429574,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Tosca, N.J.","contributorId":17354,"corporation":false,"usgs":true,"family":"Tosca","given":"N.J.","email":"","affiliations":[],"preferred":false,"id":429573,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Farrand, W. H.","contributorId":64372,"corporation":false,"usgs":true,"family":"Farrand","given":"W.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":429580,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Anderson, R.","contributorId":104191,"corporation":false,"usgs":false,"family":"Anderson","given":"R.","affiliations":[],"preferred":false,"id":429583,"contributorType":{"id":1,"text":"Authors"},"rank":12},{"text":"Knudson, A.T.","contributorId":15746,"corporation":false,"usgs":true,"family":"Knudson","given":"A.T.","email":"","affiliations":[],"preferred":false,"id":429571,"contributorType":{"id":1,"text":"Authors"},"rank":13}]}} ,{"id":70031000,"text":"70031000 - 2006 - Determination of uranyl incorporation into biogenic manganese oxides using X-ray absorption spectroscopy and scattering","interactions":[],"lastModifiedDate":"2018-10-29T09:58:58","indexId":"70031000","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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":"Determination of uranyl incorporation into biogenic manganese oxides using X-ray absorption spectroscopy and scattering","docAbstract":"Βiogenic manganese oxides are common and an important source of reactive mineral surfaces in the environment that may be potentially enhanced in bioremediation cases to improve natural attenuation. Experiments were performed in which the uranyl ion, UO22+ (U(VI)), at various concentrations was present during manganese oxide biogenesis. At all concentrations, there was strong uptake of U onto the oxides. Synchrotron-based extended X-ray absorption fine structure (EXAFS) spectroscopy and X-ray diffraction (XRD) studies were carried out to determine the molecular-scale mechanism by which uranyl is incorporated into the oxide and how this incorporation affects the resulting manganese oxide structure and mineralogy. The EXAFS experiments show that at low concentrations (<0.3 mol % U, <1 μM U(VI) in solution), U(VI) is present as a strong bidentate surface complex. At high concentrations (>2 mol % U, >4 μM U(VI) in solution), the presence of U(VI) affects the stability and structure of the Mn oxide to form poorly ordered Mn oxide tunnel structures, similar to todorokite. EXAFS modeling shows that uranyl is present in these oxides predominantly in the tunnels of the Mn oxide structure in a tridentate complex. Observations by XRD corroborate these results. Structural incorporation may lead to more stable U(VI) sequestration that may be suitable for remediation uses. These observations, combined with the very high uptake capacity of the Mn oxides, imply that Mn-oxidizing bacteria may significantly influence dissolved U(VI) concentrations in impacted waters via sorption and incorporation into Mn oxide biominerals.
If CO2 released from fossil fuel during energy production is returned to the subsurface, will it be retained for periods of time significant enough to benefit the atmosphere? Can trapping be assured in saline formations where there is no history of hydrocarbon accumulation? The Frio experiment in Texas was undertaken to provide answers to these questions.
One thousand six hundred metric tons of CO2 were injected into the Frio Formation, which underlies large areas of the United States Gulf Coast. Reservoir characterization and numerical modeling were used to design the experiment, as well as to interpret the results through history matching. Closely spaced measurements in space and time were collected to observe the evolution of immiscible and dissolved CO2 during and after injection. The high-permeability, steeply dipping sandstone allowed updip flow of supercritical CO2 as a result of the density contrast with formation brine and absence of a local structural trap.
The front of the CO2 plume moved more quickly than had been modeled. By the end of the 10-day injection, however, the plume geometry in the plane of the observation and injection wells had thickened to a distribution similar to the modeled distribution. As expected, CO2 dissolved rapidly into brine, causing pH to fall and calcite and metals to be dissolved.
Postinjection measurements, including time-lapse vertical seismic profiling transects along selected azimuths, cross-well seismic topography, and saturation logs, show that CO2 migration under gravity slowed greatly 2 months after injection, matching model predictions that significant CO2 is trapped as relative permeability decreases.
","language":"English","publisher":"Blackwell Science","doi":"10.1306/eg.11210505011","issn":"10759565","usgsCitation":"Hovorka, S.D., Benson, S.M., Doughty, C., Freifeild, B.M., Sakurai, S., Daley, T.M., Kharaka, Y.K., Holtz, M.H., Trautz, R.C., Nance, H.S., Myer, L.R., and Knauss, K.G., 2006, Measuring permanence of CO2 storage in saline formations: The Frio experiment: Environmental Geosciences, v. 13, no. 2, p. 105-121, https://doi.org/10.1306/eg.11210505011.","productDescription":"17 p.","startPage":"105","endPage":"121","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":237036,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"13","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a534de4b0c8380cd6c9af","contributors":{"authors":[{"text":"Hovorka, Susan D.","contributorId":175572,"corporation":false,"usgs":false,"family":"Hovorka","given":"Susan","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":418020,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Benson, Sally M.","contributorId":177233,"corporation":false,"usgs":false,"family":"Benson","given":"Sally","email":"","middleInitial":"M.","affiliations":[{"id":6670,"text":"Lawrence Berkeley National Laboratory, Berkeley, CA","active":true,"usgs":false}],"preferred":false,"id":418022,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Doughty, Christine","contributorId":175587,"corporation":false,"usgs":false,"family":"Doughty","given":"Christine","email":"","affiliations":[],"preferred":false,"id":418017,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Freifeild, Barry M.","contributorId":42444,"corporation":false,"usgs":false,"family":"Freifeild","given":"Barry","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":418012,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Sakurai, Shinichi","contributorId":30025,"corporation":false,"usgs":false,"family":"Sakurai","given":"Shinichi","email":"","affiliations":[{"id":12933,"text":"Bureau of Economic Geology, The University of Texas at Austin","active":true,"usgs":false}],"preferred":false,"id":418014,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Daley, Thomas M.","contributorId":175586,"corporation":false,"usgs":false,"family":"Daley","given":"Thomas","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":418016,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Kharaka, Yousif K. 0000-0001-9861-8260 ykharaka@usgs.gov","orcid":"https://orcid.org/0000-0001-9861-8260","contributorId":1928,"corporation":false,"usgs":true,"family":"Kharaka","given":"Yousif","email":"ykharaka@usgs.gov","middleInitial":"K.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":418013,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Holtz, Mark H.","contributorId":85384,"corporation":false,"usgs":false,"family":"Holtz","given":"Mark","email":"","middleInitial":"H.","affiliations":[{"id":12933,"text":"Bureau of Economic Geology, The University of Texas at Austin","active":true,"usgs":false}],"preferred":false,"id":418021,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Trautz, Robert C.","contributorId":171754,"corporation":false,"usgs":false,"family":"Trautz","given":"Robert","email":"","middleInitial":"C.","affiliations":[{"id":26941,"text":"Electric Power Research Institute, Palo Alto, CA","active":true,"usgs":false}],"preferred":false,"id":418018,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Nance, H. Seay","contributorId":59310,"corporation":false,"usgs":false,"family":"Nance","given":"H.","email":"","middleInitial":"Seay","affiliations":[{"id":12933,"text":"Bureau of Economic Geology, The University of Texas at Austin","active":true,"usgs":false}],"preferred":false,"id":418015,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Myer, Larry R.","contributorId":177239,"corporation":false,"usgs":false,"family":"Myer","given":"Larry","email":"","middleInitial":"R.","affiliations":[{"id":6670,"text":"Lawrence Berkeley National Laboratory, Berkeley, CA","active":true,"usgs":false}],"preferred":false,"id":418011,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Knauss, Kevin G.","contributorId":177240,"corporation":false,"usgs":false,"family":"Knauss","given":"Kevin","email":"","middleInitial":"G.","affiliations":[{"id":13621,"text":"Lawrence Livermore National Laboratory","active":true,"usgs":false}],"preferred":false,"id":418019,"contributorType":{"id":1,"text":"Authors"},"rank":12}]}} ,{"id":70028422,"text":"70028422 - 2006 - Late Quaternary landscape evolution in the Kunlun Mountains and Qaidam Basin, Northern Tibet: A framework for examining the links between glaciation, lake level changes and alluvial fan formation","interactions":[],"lastModifiedDate":"2012-03-12T17:20:41","indexId":"70028422","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3217,"text":"Quaternary International","active":true,"publicationSubtype":{"id":10}},"title":"Late Quaternary landscape evolution in the Kunlun Mountains and Qaidam Basin, Northern Tibet: A framework for examining the links between glaciation, lake level changes and alluvial fan formation","docAbstract":"The Qaidam Basin in Northern Tibet is one of the largest hyper-arid intermontane basins on Earth. Alluvial fans, pediment surfaces, shorelines and a thick succession of sediments within the basin, coupled with moraines and associated landforms in the adjacent high mountain catchments of the Kunlun Mountains, record a complex history of Late Quaternary paleoenvironmental change and landscape evolution. The region provides an ideal natural laboratory to examine the interaction between tectonics and climate within a continent-continent collision zone, and to quantify rates of landscape evolution as controlled by climate and the associated glacial and hydrological changes in hyper-arid and adjacent high-altitude environments. Geomorphic mapping, analysis of landforms and sediments, and terrestrial cosmogenic radionuclide surface exposure and optically stimulated luminescence dating serve to define the timing of formation of Late Quaternary landforms along the southern and northwestern margins of the Qaidam Basin, and in the Burhan Budai Shan of the Kunlun Mountains adjacent to the basin on the south. These dates provide a framework that suggests links between climatic amelioration, deglaciation, lake desiccation and alluvial fan evolution. At least three glacial advances are defined in the Burham Budai Shan of the Kunlun Mountains. On the northern side of this range these occurred in the penultimate glacial cycle or early in the last glacial cycle, during the Last Glacial Maximum (LGM)/Lateglacial and during the Holocene. On the south side of the range, advances occurred during the penultimate glacial cycle, MIS-3, and possibly the LGM, Lateglacial or Holocene. Several distinct phases of alluvial fan sedimentation are likewise defined. Alluvial fans formed on the southern side of the Kunlun Mountains prior to 200 ka. Ice-contact alluvial fans formed during the penultimate glacial and during MIS-3. Extensive incised alluvial fans that form the main valley fills north of the Burham Budai and extend into the Qaidam Basin are dated to ???30 ka. These ages suggest that there was a period of alluvial fan aggradation and valley filling that persisted until desiccation of the large lakes in the Qaidam Basin post ???30 ka led to base level lowering and active incision of streams into the valley fills. The continued Lateglacial and Holocene desiccation likely led to further degradation of the valley fills. Ice wedge casts in the Qaidam Basin date to ???15 ka, indicating significant Lateglacial climatic amelioration, while Holocene loess deposits north of the Burham Bdudai suggest that aridity has increased in the region since the early Holocene. From these observations, we infer that the major landscape changes within high glaciated mountains and their adjacent hyper-arid intermontane basins, such as the Kunlun Mountains and Qaidam Basin, occur rapidly over millennial timescales during periods of climatic instability. ?? 2006 Elsevier Ltd and INQUA.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Quaternary International","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.quaint.2006.02.008","issn":"10406182","usgsCitation":"Owen, L., Finkel, R., Haizhou, M., and Barnard, P., 2006, Late Quaternary landscape evolution in the Kunlun Mountains and Qaidam Basin, Northern Tibet: A framework for examining the links between glaciation, lake level changes and alluvial fan formation: Quaternary International, v. 154-155, p. 73-86, https://doi.org/10.1016/j.quaint.2006.02.008.","startPage":"73","endPage":"86","numberOfPages":"14","costCenters":[],"links":[{"id":236896,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":210082,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.quaint.2006.02.008"}],"volume":"154-155","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a452fe4b0c8380cd670d5","contributors":{"authors":[{"text":"Owen, L.A.","contributorId":94836,"corporation":false,"usgs":true,"family":"Owen","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":417983,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Finkel, R.C.","contributorId":79677,"corporation":false,"usgs":true,"family":"Finkel","given":"R.C.","email":"","affiliations":[],"preferred":false,"id":417981,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Haizhou, M.","contributorId":80889,"corporation":false,"usgs":true,"family":"Haizhou","given":"M.","affiliations":[],"preferred":false,"id":417982,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Barnard, P.L.","contributorId":20527,"corporation":false,"usgs":true,"family":"Barnard","given":"P.L.","email":"","affiliations":[],"preferred":false,"id":417980,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70028409,"text":"70028409 - 2006 - Using self-organizing maps to determine observation threshold limit predictions in highly variant data","interactions":[],"lastModifiedDate":"2012-03-12T17:20:54","indexId":"70028409","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Using self-organizing maps to determine observation threshold limit predictions in highly variant data","docAbstract":"A significant data quality challenge for highly variant systems surrounds the limited ability to quantify operationally reasonable limits on the data elements being collected and provide reasonable threshold predictions. In many instances, the number of influences that drive a resulting value or operational range is too large to enable physical sampling for each influencer, or is too complicated to accurately model in an explicit simulation. An alternative method to determine reasonable observation thresholds is to employ an automation algorithm that would emulate a human analyst visually inspecting data for limits. Using the visualization technique of self-organizing maps (SOM) on data having poorly understood relationships, a methodology for determining threshold limits was developed. To illustrate this approach, analysis of environmental influences that drive the abundance of a target indicator species (the pink shrimp, Farfantepenaeus duorarum) provided a real example of applicability. The relationship between salinity and temperature and abundance of F. duorarum is well documented, but the effect of changes in water quality upstream on pink shrimp abundance is not well understood. The highly variant nature surrounding catch of a specific number of organisms in the wild, and the data available from up-stream hydrology measures for salinity and temperature, made this an ideal candidate for the approach to provide a determination about the influence of changes in hydrology on populations of organisms.","largerWorkTitle":"Proceedings of SPIE - The International Society for Optical Engineering","conferenceTitle":"Signal Processing, Sensor Fusion, and Target Recognition XV","conferenceDate":"17 April 2006 through 19 April 2006","conferenceLocation":"Kissimmee, FL","language":"English","doi":"10.1117/12.667802","issn":"0277786X","isbn":"0819462918; 9780819462916","usgsCitation":"Paganoni, C., Chang, K., and Robblee, M., 2006, Using self-organizing maps to determine observation threshold limit predictions in highly variant data, in Proceedings of SPIE - The International Society for Optical Engineering, v. 6235, Kissimmee, FL, 17 April 2006 through 19 April 2006, https://doi.org/10.1117/12.667802.","costCenters":[],"links":[{"id":210351,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1117/12.667802"},{"id":237246,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"6235","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc09be4b08c986b32a208","contributors":{"authors":[{"text":"Paganoni, C.A.","contributorId":10984,"corporation":false,"usgs":true,"family":"Paganoni","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":417937,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chang, K.C.","contributorId":44732,"corporation":false,"usgs":true,"family":"Chang","given":"K.C.","email":"","affiliations":[],"preferred":false,"id":417939,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Robblee, M. B.","contributorId":23879,"corporation":false,"usgs":true,"family":"Robblee","given":"M. B.","affiliations":[],"preferred":false,"id":417938,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70028380,"text":"70028380 - 2006 - Spatial patterns of fish communities along two estuarine gradients in southern Florida","interactions":[],"lastModifiedDate":"2014-10-24T15:31:43","indexId":"70028380","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1919,"text":"Hydrobiologia","onlineIssn":"1573-5117","printIssn":"0018-8158","active":true,"publicationSubtype":{"id":10}},"title":"Spatial patterns of fish communities along two estuarine gradients in southern Florida","docAbstract":"In tropical and subtropical estuaries, gradients of primary productivity and salinity are generally invoked to explain patterns in community structure and standing crops of fishes. We documented spatial and temporal patterns in fish community structure and standing crops along salinity and nutrient gradients in two subtropical drainages of Everglades National Park, USA. The Shark River drains into the Gulf of Mexico and experiences diurnal tides carrying relatively nutrient enriched waters, while Taylor River is more hydrologically isolated by the oligohaline Florida Bay and experiences no discernable lunar tides. We hypothesized that the more nutrient enriched system would support higher standing crops of fishes in its mangrove zone. We collected 50 species of fish from January 2000 to April 2004 at six sampling sites spanning fresh to brackish salinities in both the Shark and Taylor River drainages. Contrary to expectations, we observed lower standing crops and density of fishes in the more nutrient rich tidal mangrove forest of the Shark River than in the less nutrient rich mangrove habitats bordering the Taylor River. Tidal mangrove habitats in the Shark River were dominated by salt-tolerant fish and displayed lower species richness than mangrove communities in the Taylor River, which included more freshwater taxa and yielded relatively higher richness. These differences were maintained even after controlling for salinity at the time of sampling. Small-scale topographic relief differs between these two systems, possibly created by tidal action in the Shark River. We propose that this difference in topography limits movement of fishes from upstream marshes into the fringing mangrove forest in the Shark River system, but not the Taylor River system. Understanding the influence of habitat structure, including connectivity, on aquatic communities is important to anticipate effects of construction and operational alternatives associated with restoration of the Everglades ecosystem.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrobiologia","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Springer","doi":"10.1007/s10750-006-0144-x","issn":"00188158","usgsCitation":"Green, D., Trexler, J., Lorenz, J., McIvor, C., and Philippi, T., 2006, Spatial patterns of fish communities along two estuarine gradients in southern Florida: Hydrobiologia, v. 569, no. 1, p. 387-399, https://doi.org/10.1007/s10750-006-0144-x.","productDescription":"13 p.","startPage":"387","endPage":"399","numberOfPages":"13","costCenters":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true}],"links":[{"id":236822,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":210027,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10750-006-0144-x"}],"country":"United States","state":"Florida","otherGeospatial":"Everglades National Park","volume":"569","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b949de4b08c986b31abaa","contributors":{"authors":[{"text":"Green, D.P.J.","contributorId":20963,"corporation":false,"usgs":true,"family":"Green","given":"D.P.J.","email":"","affiliations":[],"preferred":false,"id":417800,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Trexler, J.C.","contributorId":23108,"corporation":false,"usgs":true,"family":"Trexler","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":417801,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lorenz, J.J.","contributorId":67058,"corporation":false,"usgs":true,"family":"Lorenz","given":"J.J.","email":"","affiliations":[],"preferred":false,"id":417803,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McIvor, C.C.","contributorId":38104,"corporation":false,"usgs":true,"family":"McIvor","given":"C.C.","email":"","affiliations":[],"preferred":false,"id":417802,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Philippi, T.","contributorId":78142,"corporation":false,"usgs":true,"family":"Philippi","given":"T.","affiliations":[],"preferred":false,"id":417804,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70028354,"text":"70028354 - 2006 - Effects of permafrost melting on CO2 and CH4 exchange of a poorly drained black spruce lowland","interactions":[],"lastModifiedDate":"2018-10-26T09:48:26","indexId":"70028354","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2319,"text":"Journal of Geophysical Research G: Biogeosciences","active":true,"publicationSubtype":{"id":10}},"title":"Effects of permafrost melting on CO2 and CH4 exchange of a poorly drained black spruce lowland","docAbstract":"[1] Permafrost melting is occurring in areas of the boreal forest region where large amounts of carbon (C) are stored in organic soils. We measured soil respiration, net CO2 flux, and net CH4 flux during May–September 2003 and March 2004 in a black spruce lowland in interior Alaska to better understand how permafrost thaw in poorly drained landscapes affects land‐atmosphere CO2 and CH4 exchange. Sites included peat soils underlain by permafrost at ∼0.4 m depth (permafrost plateau, PP), four thermokarst wetlands (TW) having no permafrost in the upper 2.2 m, and peat soils bordering the thermokarst wetlands having permafrost at ∼0.5 m depth (thermokarst edges, TE). Soil respiration rates were not significantly different among the sites, and 5‐cm soil temperature explained 50–91% of the seasonal variability in soil respiration within the sites. Groundcover vegetation photosynthesis (calculated as net CO2 minus soil respiration) was significantly different among the sites (TW > TE > PP), which can be partly attributed to the difference in photosynthetically active radiation reaching the ground at each site type. Methane emission rates were 15 to 28 times greater from TW than from TE and PP. We modeled annual soil respiration and groundcover vegetation photosynthesis using soil temperature and radiation data, and CH4 flux by linear interpolation. We estimated all sites as net C gas sources to the atmosphere (not including tree CO2 uptake at PP and TE), although the ranges in estimates when accounting for errors were large enough that TE and TW may have been net C sinks.
Years of discharge measurements that precede and follow the cataclysmic 1980 eruption of Mount St. Helens, Washington, provide an exceptional opportunity to examine the responses of peak flows to abrupt, widespread, devastating landscape disturbance. Multiple basins surrounding Mount St. Helens (300–1300 km2 drainage areas) were variously disturbed by: (1) a debris avalanche that buried 60 km2 of valley; (2) a lateral volcanic blast and associated pyroclastic flow that destroyed 550 km2 of mature forest and blanketed the landscape with silt-capped lithic tephra; (3) debris flows that reamed riparian corridors and deposited tens to hundreds of centimeters of gravelly sand on valley floors; and (4) a Plinian tephra fall that blanketed areas proximal to the volcano with up to tens of centimeters of pumiceous silt, sand, and gravel. The spatially complex disturbances produced a variety of potentially compensating effects that interacted with and influenced hydrological responses. Changes to water transfer on hillslopes and to flow storage and routing along channels both enhanced and retarded runoff. Rapid post-eruption modifications of hillslope surface textures, adjustments of channel networks, and vegetation recovery, in conjunction with the complex nature of the eruptive impacts and strong seasonal variability in regional climate hindered a consistent or persistent shift in peak discharges. Overall, we detected a short-lived (5–10 yr) increase in the magnitudes of autumn and winter peak flows. In general, peak flows were larger, and moderate to large flows (>Q2 yr) were more substantively affected than predicted by early modeling efforts. Proportional increases in the magnitudes of both small and large flows in basins subject to severe channel disturbances, but not in basins subject solely to hillslope disturbances, suggest that eruption-induced modifications to flow efficiency along alluvial channels that have very mobile beds differentially affected flows of various magnitudes and likely played a prominent, and additional, role affecting the nature of the hydrological response.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/B25914.1","issn":"00167606","usgsCitation":"Major, J.J., and Mark, L.E., 2006, Peak flow responses to landscape disturbances caused by the cataclysmic 1980 eruption of Mount St. Helens, Washington: Geological Society of America Bulletin, v. 118, no. 7-8, p. 938-958, https://doi.org/10.1130/B25914.1.","productDescription":"21 p.","startPage":"938","endPage":"958","numberOfPages":"21","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"links":[{"id":236820,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Washington","otherGeospatial":"Mount St. Helens","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -122.96173095703125,\n 45.539060482134495\n ],\n [\n -122.96173095703125,\n 46.81133924039194\n ],\n [\n -121.52252197265626,\n 46.81133924039194\n ],\n [\n -121.52252197265626,\n 45.539060482134495\n ],\n [\n -122.96173095703125,\n 45.539060482134495\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"118","issue":"7-8","noUsgsAuthors":false,"publicationDate":"2006-06-30","publicationStatus":"PW","scienceBaseUri":"505a760de4b0c8380cd77ec9","contributors":{"authors":[{"text":"Major, Jon J. 0000-0003-2449-4466 jjmajor@usgs.gov","orcid":"https://orcid.org/0000-0003-2449-4466","contributorId":439,"corporation":false,"usgs":true,"family":"Major","given":"Jon","email":"jjmajor@usgs.gov","middleInitial":"J.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":417609,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mark, Linda E.","contributorId":177476,"corporation":false,"usgs":true,"family":"Mark","given":"Linda","email":"","middleInitial":"E.","affiliations":[{"id":157,"text":"Cascades Volcano Observatory","active":false,"usgs":true}],"preferred":false,"id":417610,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70028342,"text":"70028342 - 2006 - Pharmaceuticals and other organic chemicals in selected north-central and northwestern Arkansas streams","interactions":[],"lastModifiedDate":"2018-10-22T10:19:03","indexId":"70028342","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2262,"text":"Journal of Environmental Quality","active":true,"publicationSubtype":{"id":10}},"title":"Pharmaceuticals and other organic chemicals in selected north-central and northwestern Arkansas streams","docAbstract":"Recently, our attention has focused on the low level detection of many antibiotics, pharmaceuticals, and other organic chemicals in water resources. The limited studies available suggest that urban or rural streams receiving wastewater effluent are more susceptible to contamination. The purpose of this study was to evaluate the occurrence of antibiotics, pharmaceuticals, and other organic chemicals at 18 sites on seven selected streams in Arkansas, USA, during March, April, and August 2004. Water samples were collected upstream and downstream from the influence of effluent discharges in northwestern Arkansas and at one site on a relatively undeveloped stream in north-central Arkansas. At least one antibiotic, pharmaceutical, or other organic chemical was detected at all sites, except at Spavinaw Creek near Mayesville, Arkansas. The greatest number of detections was observed at Mud Creek downstream from an effluent discharge, including 31 pharmaceuticals and other organic chemicals. The detection of these chemicals occurred in higher frequency at sites downstream from effluent discharges compared to those sites upstream from effluent discharges; total chemical concentration was also greater downstream. Wastewater effluent discharge increased the concentrations of detergent metabolites, fire retardants, fragrances and flavors, and steroids in these streams. Antibiotics and associated degradation products were only found at two streams downstream from effluent discharges. Overall, 42 of the 108 chemicals targeted in this study were found in water samples from at least one site, and the most frequently detected organic chemicals included caffeine, phenol, para-cresol, and acetyl hexamethyl tetrahydro naphthalene (AHTN).
","language":"English","publisher":"ACSESS","doi":"10.2134/jeq2005.0248","issn":"00472425","usgsCitation":"Haggard, B., Galloway, J., Green, W.R., and Meyer, M.T., 2006, Pharmaceuticals and other organic chemicals in selected north-central and northwestern Arkansas streams: Journal of Environmental Quality, v. 35, no. 4, p. 1078-1087, https://doi.org/10.2134/jeq2005.0248.","productDescription":"10 p.","startPage":"1078","endPage":"1087","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":477376,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.2134/jeq2005.0248","text":"Publisher Index Page"},{"id":237344,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":210431,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.2134/jeq2005.0248"}],"volume":"35","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a786de4b0c8380cd786c4","contributors":{"authors":[{"text":"Haggard, B. E.","contributorId":69755,"corporation":false,"usgs":true,"family":"Haggard","given":"B. E.","affiliations":[],"preferred":false,"id":417604,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Galloway, J.M.","contributorId":65114,"corporation":false,"usgs":true,"family":"Galloway","given":"J.M.","email":"","affiliations":[],"preferred":false,"id":417602,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Green, W. R.","contributorId":68354,"corporation":false,"usgs":true,"family":"Green","given":"W.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":417603,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Meyer, M. T.","contributorId":92279,"corporation":false,"usgs":true,"family":"Meyer","given":"M.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":417605,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70028331,"text":"70028331 - 2006 - Use of radars to monitor stream discharge by noncontact methods","interactions":[],"lastModifiedDate":"2018-10-26T08:00:07","indexId":"70028331","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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":"Use of radars to monitor stream discharge by noncontact methods","docAbstract":"Conventional measurements of river flows are costly, time‐consuming, and frequently dangerous. This report evaluates the use of a continuous wave microwave radar, a monostatic UHF Doppler radar, a pulsed Doppler microwave radar, and a ground‐penetrating radar to measure river flows continuously over long periods and without touching the water with any instruments. The experiments duplicate the flow records from conventional stream gauging stations on the San Joaquin River in California and the Cowlitz River in Washington. The purpose of the experiments was to directly measure the parameters necessary to compute flow: surface velocity (converted to mean velocity) and cross‐sectional area, thereby avoiding the uncertainty, complexity, and cost of maintaining rating curves. River channel cross sections were measured by ground‐penetrating radar suspended above the river. River surface water velocity was obtained by Bragg scattering of microwave and UHF Doppler radars, and the surface velocity data were converted to mean velocity on the basis of detailed velocity profiles measured by current meters and hydroacoustic instruments. Experiments using these radars to acquire a continuous record of flow were conducted for 4 weeks on the San Joaquin River and for 16 weeks on the Cowlitz River. At the San Joaquin River the radar noncontact measurements produced discharges more than 20% higher than the other independent measurements in the early part of the experiment. After the first 3 days, the noncontact radar discharge measurements were within 5% of the rating values. On the Cowlitz River at Castle Rock, correlation coefficients between the USGS stream gauging station rating curve discharge and discharge computed from three different Doppler radar systems and GPR data over the 16 week experiment were 0.883, 0.969, and 0.992. Noncontact radar results were within a few percent of discharge values obtained by gauging station, current meter, and hydroacoustic methods. Time series of surface velocity obtained by different radars in the Cowlitz River experiment also show small‐amplitude pulsations not found in stage records that reflect tidal energy at the gauging station. Noncontact discharge measurements made during a flood on 30 January 2004 agreed with the rated discharge to within 5%. Measurement at both field sites confirm that lognormal velocity profiles exist for a wide range of flows in these rivers, and mean velocity is approximately 0.85 times measured surface velocity. Noncontact methods of flow measurement appear to (1) be as accurate as conventional methods, (2) obtain data when standard contact methods are dangerous or cannot be obtained, and (3) provide insight into flow dynamics not available from detailed stage records alone.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2005WR004430","usgsCitation":"Costa, J.E., Cheng, R.T., Haeni, F., Melcher, N., Spicer, K., Hayes, E., Plant, W., Hayes, K., Teague, C., and Barrick, D., 2006, Use of radars to monitor stream discharge by noncontact methods: Water Resources Research, v. 42, no. 7, W07422; 14 p., https://doi.org/10.1029/2005WR004430.","productDescription":"W07422; 14 p.","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":237139,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"42","issue":"7","noUsgsAuthors":false,"publicationDate":"2006-07-27","publicationStatus":"PW","scienceBaseUri":"505bbf61e4b08c986b329b17","contributors":{"authors":[{"text":"Costa, J. E.","contributorId":28977,"corporation":false,"usgs":true,"family":"Costa","given":"J.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":417563,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cheng, R. T.","contributorId":23138,"corporation":false,"usgs":false,"family":"Cheng","given":"R.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":417562,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Haeni, F.P.","contributorId":87105,"corporation":false,"usgs":true,"family":"Haeni","given":"F.P.","affiliations":[],"preferred":false,"id":417570,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Melcher, N.","contributorId":74187,"corporation":false,"usgs":true,"family":"Melcher","given":"N.","email":"","affiliations":[],"preferred":false,"id":417569,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Spicer, K.R.","contributorId":67230,"corporation":false,"usgs":true,"family":"Spicer","given":"K.R.","email":"","affiliations":[],"preferred":false,"id":417568,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Hayes, E.","contributorId":29158,"corporation":false,"usgs":true,"family":"Hayes","given":"E.","affiliations":[],"preferred":false,"id":417564,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Plant, W.","contributorId":62398,"corporation":false,"usgs":true,"family":"Plant","given":"W.","email":"","affiliations":[],"preferred":false,"id":417567,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Hayes, K.","contributorId":55178,"corporation":false,"usgs":true,"family":"Hayes","given":"K.","email":"","affiliations":[],"preferred":false,"id":417566,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Teague, C.","contributorId":30412,"corporation":false,"usgs":true,"family":"Teague","given":"C.","email":"","affiliations":[],"preferred":false,"id":417565,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Barrick, D.","contributorId":105888,"corporation":false,"usgs":true,"family":"Barrick","given":"D.","email":"","affiliations":[],"preferred":false,"id":417571,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}} ,{"id":70028328,"text":"70028328 - 2006 - Evaluating uncertainty in predicting spatially variable representative elementary scales in fractured aquifers, with application to Turkey Creek Basin, Colorado","interactions":[],"lastModifiedDate":"2018-04-03T16:58:10","indexId":"70028328","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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":"Evaluating uncertainty in predicting spatially variable representative elementary scales in fractured aquifers, with application to Turkey Creek Basin, Colorado","docAbstract":"Computational limitations and sparse field data often mandate use of continuum representation for modeling hydrologic processes in large‐scale fractured aquifers. Selecting appropriate element size is of primary importance because continuum approximation is not valid for all scales. The traditional approach is to select elements by identifying a single representative elementary scale (RES) for the region of interest. Recent advances indicate RES may be spatially variable, prompting unanswered questions regarding the ability of sparse data to spatially resolve continuum equivalents in fractured aquifers. We address this uncertainty of estimating RES using two techniques. In one technique we employ data‐conditioned realizations generated by sequential Gaussian simulation. For the other we develop a new approach using conditioned random walks and nonparametric bootstrapping (CRWN). We evaluate the effectiveness of each method under three fracture densities, three data sets, and two groups of RES analysis parameters. In sum, 18 separate RES analyses are evaluated, which indicate RES magnitudes may be reasonably bounded using uncertainty analysis, even for limited data sets and complex fracture structure. In addition, we conduct a field study to estimate RES magnitudes and resulting uncertainty for Turkey Creek Basin, a crystalline fractured rock aquifer located 30 km southwest of Denver, Colorado. Analyses indicate RES does not correlate to rock type or local relief in several instances but is generally lower within incised creek valleys and higher along mountain fronts. Results of this study suggest that (1) CRWN is an effective and computationally efficient method to estimate uncertainty, (2) RES predictions are well constrained using uncertainty analysis, and (3) for aquifers such as Turkey Creek Basin, spatial variability of RES is significant and complex.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2005WR004431","usgsCitation":"Wellman, T., and Poeter, E.P., 2006, Evaluating uncertainty in predicting spatially variable representative elementary scales in fractured aquifers, with application to Turkey Creek Basin, Colorado: Water Resources Research, v. 42, no. 8, Article W08410; 21 p., https://doi.org/10.1029/2005WR004431.","productDescription":"Article W08410; 21 p.","costCenters":[],"links":[{"id":237030,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"42","issue":"8","noUsgsAuthors":false,"publicationDate":"2006-08-09","publicationStatus":"PW","scienceBaseUri":"505a0c03e4b0c8380cd529ce","contributors":{"authors":[{"text":"Wellman, Tristan P.","contributorId":56500,"corporation":false,"usgs":true,"family":"Wellman","given":"Tristan P.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":false,"id":417547,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Poeter, Eileen P.","contributorId":78805,"corporation":false,"usgs":true,"family":"Poeter","given":"Eileen","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":417546,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70028326,"text":"70028326 - 2006 - Nitrogen sources and cycling in the San Francisco Bay estuary: A nitrate dual isotopic composition approach","interactions":[],"lastModifiedDate":"2018-10-29T09:54:23","indexId":"70028326","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Nitrogen sources and cycling in the San Francisco Bay estuary: A nitrate dual isotopic composition approach","docAbstract":"We used the dual isotopic composition of nitrate (δ15N and δ18O) within the estuarine system of San Francisco (SF) Bay, California, to explore the utility of this approach for tracing sources and cycling of nitrate (NO2−). Surface water samples from 49 sites within the estuary were sampled during July–August 2004. Spatial variability in the isotopic composition suggests that there are multiple sources of nitrate to the bay ecosystem including seawater, several rivers and creeks, and sewage effluent. The spatial distribution of nitrate from these sources is heavily modulated by the hydrodynamics of the estuary. Mixing along the estuarine salinity gradient is the main control on the spatial variations in isotopic composition of nitrate within the northern arm of SF Bay. However, the nitrate isotopic composition in the southern arm of SF Bay exhibited a combination of source mixing and phytoplankton drawdown due mostly to the long residence time during the summer study period. Very low δ18ONO3 values (as low as −5.0%) at the Sacramento–San Joaquin River delta region give rise to a wide range of δ18ONO3 values in the SF Bay system. The range in δ18ONO3 values is more than twice that of δ15NNO3, suggesting that δ18ONO3 is an even more sensitive tool for tracing nitrate sources and cycling than δ15NNO3.
","language":"English","publisher":"ASLO","doi":"10.4319/lo.2006.51.4.1654 ","issn":"00243590","usgsCitation":"Wankel, S.D., Kendall, C., Francis, C., and Paytan, A., 2006, Nitrogen sources and cycling in the San Francisco Bay estuary: A nitrate dual isotopic composition approach: Limnology and Oceanography, v. 51, no. 4, p. 1654-1664, https://doi.org/10.4319/lo.2006.51.4.1654 .","productDescription":"11 p.","startPage":"1654","endPage":"1664","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":236994,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"51","issue":"4","noUsgsAuthors":false,"publicationDate":"2006-07-15","publicationStatus":"PW","scienceBaseUri":"505a66f4e4b0c8380cd730c4","contributors":{"authors":[{"text":"Wankel, Scott D.","contributorId":98076,"corporation":false,"usgs":true,"family":"Wankel","given":"Scott","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":417539,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kendall, C. 0000-0002-0247-3405","orcid":"https://orcid.org/0000-0002-0247-3405","contributorId":35050,"corporation":false,"usgs":true,"family":"Kendall","given":"C.","affiliations":[],"preferred":false,"id":417537,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Francis, C.A.","contributorId":92859,"corporation":false,"usgs":true,"family":"Francis","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":417538,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Paytan, A.","contributorId":98926,"corporation":false,"usgs":true,"family":"Paytan","given":"A.","affiliations":[],"preferred":false,"id":417540,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70028325,"text":"70028325 - 2006 - Multiphase, multicomponent parameter estimation for liquid and vapor fluxes in deep arid systems using hydrologic data and natural environmental tracers","interactions":[],"lastModifiedDate":"2018-10-22T10:54:09","indexId":"70028325","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3674,"text":"Vadose Zone Journal","active":true,"publicationSubtype":{"id":10}},"title":"Multiphase, multicomponent parameter estimation for liquid and vapor fluxes in deep arid systems using hydrologic data and natural environmental tracers","docAbstract":"Multiphase, multicomponent numerical models of long-term unsaturated-zone liquid and vapor movement were created for a thick alluvial basin at the Nevada Test Site to predict present-day liquid and vapor fluxes. The numerical models are based on recently developed conceptual models of unsaturated-zone moisture movement in thick alluvium that explain present-day water potential and tracer profiles in terms of major climate and vegetation transitions that have occurred during the past 10 000 yr or more. The numerical models were calibrated using borehole hydrologic and environmental tracer data available from a low-level radioactive waste management site located in a former nuclear weapons testing area. The environmental tracer data used in the model calibration includes tracers that migrate in both the liquid and vapor phases (δD, δ18O) and tracers that migrate solely as dissolved solutes (Cl), thus enabling the estimation of some gas-phase as well as liquid-phase transport parameters. Parameter uncertainties and correlations identified during model calibration were used to generate parameter combinations for a set of Monte Carlo simulations to more fully characterize the uncertainty in liquid and vapor fluxes. The calculated background liquid and vapor fluxes decrease as the estimated time since the transition to the present-day arid climate increases. However, on the whole, the estimated fluxes display relatively little variability because correlations among parameters tend to create parameter sets for which changes in some parameters offset the effects of others in the set. Independent estimates on the timing since the climate transition established from packrat midden data were essential for constraining the model calibration results. The study demonstrates the utility of environmental tracer data in developing numerical models of liquid- and gas-phase moisture movement and the importance of considering parameter correlations when using Monte Carlo analysis to characterize the uncertainty in moisture fluxes.
","language":"English","publisher":"ACSESS","doi":"10.2136/vzj2006.0021","usgsCitation":"Kwicklis, E.M., Wolfsberg, A.V., Stauffer, P.H., Walvoord, M.A., and Sully, M.J., 2006, Multiphase, multicomponent parameter estimation for liquid and vapor fluxes in deep arid systems using hydrologic data and natural environmental tracers: Vadose Zone Journal, v. 5, no. 3, p. 934-950, https://doi.org/10.2136/vzj2006.0021.","productDescription":"17 p.","startPage":"934","endPage":"950","costCenters":[{"id":465,"text":"Nevada Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":236993,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"5","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a605ae4b0c8380cd713c0","contributors":{"authors":[{"text":"Kwicklis, Edward M.","contributorId":25970,"corporation":false,"usgs":true,"family":"Kwicklis","given":"Edward","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":417535,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wolfsberg, Andrew V.","contributorId":22530,"corporation":false,"usgs":false,"family":"Wolfsberg","given":"Andrew","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":417532,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Stauffer, Philip H.","contributorId":69262,"corporation":false,"usgs":false,"family":"Stauffer","given":"Philip","email":"","middleInitial":"H.","affiliations":[{"id":13447,"text":"Los Alamos National Laboratory","active":true,"usgs":false}],"preferred":false,"id":417533,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Walvoord, Michelle Ann 0000-0003-4269-8366 walvoord@usgs.gov","orcid":"https://orcid.org/0000-0003-4269-8366","contributorId":147211,"corporation":false,"usgs":true,"family":"Walvoord","given":"Michelle","email":"walvoord@usgs.gov","middleInitial":"Ann","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":417536,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Sully, Michael J.","contributorId":82911,"corporation":false,"usgs":false,"family":"Sully","given":"Michael","email":"","middleInitial":"J.","affiliations":[{"id":16973,"text":"Neptune and Company Inc.","active":true,"usgs":false}],"preferred":false,"id":417534,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70028320,"text":"70028320 - 2006 - Flow-specific trends in river-water quality resulting from the effects of the clean air act in three mesoscale, forested river basins in the northeastern United States through 2002","interactions":[],"lastModifiedDate":"2012-03-12T17:20:44","indexId":"70028320","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1552,"text":"Environmental Monitoring and Assessment","onlineIssn":"1573-2959","printIssn":"0167-6369","active":true,"publicationSubtype":{"id":10}},"title":"Flow-specific trends in river-water quality resulting from the effects of the clean air act in three mesoscale, forested river basins in the northeastern United States through 2002","docAbstract":"Two new methods for assessing temporal trends in stream-solute concentrations at specific streamflow ranges were applied to long (40 to 50-year) but sparse (bi-weekly to quarterly sampling) stream-water quality data collected at three forested mesoscale basins along an atmospheric deposition gradient in the northeastern United States (one in north-central Pennsylvania, one in southeastern New York, and one in eastern Maine). The three data sets span the period since the implementation of the Clean Air Act in 1970 and its subsequent amendments. Declining sulfate (SO2-4) trends since the mid 1960s were identified for all 3 rivers by one or more of the 4 methods of trend detection used. Flow-specific trends were assessed by segmenting the data sets into 3-year and 6-year blocks, then determining concentration-discharge relationships for each block. Declining sulfate (SO2-4) trends at median flow were similar to trends determined using a Seasonal Kendall Tau test and Sen slope estimator. The trend of declining SO2-4 concentrations differed at high, median and low flow since the mid 1980s at YWC and NR, and at high and low flow at WR, but the trends leveled or reversed at high flow from 1999 through 2002. Trends for the period of record at high flows were similar to medium- and low-flow trends for Ca2+ + Mg2+ concentrations at WR, non-significant at YWC, and were more negative at low flow than at high flow at NR; trends in nitrate (NO-3), and alkalinity (ALK) concentrations were different at different flow conditions, and in ways that are consistent with the hydrology and deposition history at each watershed. Quarterly sampling is adequate for assessing average-flow trends in the chemical parameters assessed over long time periods (???decades). However, with even a modest effort at sampling a range of flow conditions within each year, trends at specified flows for constituents with strong concentration-discharge relationships can be evaluated and may allow early detection of ecosystem response to climate change and pollution management strategies. ?? Springer Science+Business Media, B.V. 2006.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Monitoring and Assessment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10661-005-9028-1","issn":"01676369","usgsCitation":"Murdoch, P., and Shanley, J.B., 2006, Flow-specific trends in river-water quality resulting from the effects of the clean air act in three mesoscale, forested river basins in the northeastern United States through 2002: Environmental Monitoring and Assessment, v. 120, no. 1-3, p. 1-25, https://doi.org/10.1007/s10661-005-9028-1.","startPage":"1","endPage":"25","numberOfPages":"25","costCenters":[],"links":[{"id":236922,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":210103,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10661-005-9028-1"}],"volume":"120","issue":"1-3","noUsgsAuthors":false,"publicationDate":"2006-08-01","publicationStatus":"PW","scienceBaseUri":"505a125de4b0c8380cd5429a","contributors":{"authors":[{"text":"Murdoch, Peter S.","contributorId":73547,"corporation":false,"usgs":true,"family":"Murdoch","given":"Peter S.","affiliations":[],"preferred":false,"id":417520,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shanley, J. B.","contributorId":52226,"corporation":false,"usgs":true,"family":"Shanley","given":"J.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":417519,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70028312,"text":"70028312 - 2006 - Recharge processes drive sulfate reduction in an alluvial aquifer contaminated with landfill leachate","interactions":[],"lastModifiedDate":"2018-10-29T07:46:32","indexId":"70028312","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Recharge processes drive sulfate reduction in an alluvial aquifer contaminated with landfill leachate","docAbstract":"Natural attenuation of contaminants in groundwater depends on an adequate supply of electron acceptors to stimulate biodegradation. In an alluvial aquifer contaminated with leachate from an unlined municipal landfill, the mechanism of recharge infiltration was investigated as a source of electron acceptors. Water samples were collected monthly at closely spaced intervals in the top 2 m of the saturated zone from a leachate-contaminated well and an uncontaminated well, and analyzed for δ18O, δ2H, non-volatile dissolved organic carbon (NVDOC), SO42−, NO3− and Cl−. Monthly recharge amounts were quantified using the offset of the δ18O or δ2H from the local meteoric water line as a parameter to distinguish water types, as evaporation and methanogenesis caused isotopic enrichment in waters from different sources. Presence of dissolved SO42− in the top 1 to 2 m of the saturated zone was associated with recharge; SO42− averaged 2.2 mM, with maximum concentrations of 15 mM. Nitrate was observed near the water table at the contaminated site at concentrations up to 4.6 mM. Temporal monitoring of δ2H and SO42− showed that vertical transport of recharge carried SO42− to depths up to 1.75 m below the water table, supplying an additional electron acceptor to the predominantly methanogenic leachate plume. Measurements of δ34S in SO42−indicated both SO42− reduction and sulfide oxidation were occurring in the aquifer. Depth-integrated net SO42− reduction rates, calculated using the natural Cl−gradient as a conservative tracer, ranged from 7.5 × 10− 3 to 0.61 mM·d− 1 (over various depth intervals from 0.45 to 1.75 m). Sulfate reduction occurred at both the contaminated and uncontaminated sites; however, median SO42− reduction rates were higher at the contaminated site. Although estimated SO42− reduction rates are relatively high, significant decreases in NVDOC were not observed at the contaminated site. Organic compounds more labile than the leachate NVDOC may be present in the root zone, and SO42− reduction may be coupled to methane oxidation. The results show that sulfur (and possibly nitrogen) redox processes within the top 2 m of the aquifer are directly related to recharge timing and seasonal water level changes in the aquifer. The results suggest that SO42−reduction associated with the infiltration of recharge may be a significant factor affecting natural attenuation of contaminants in alluvial aquifers.