Alpine/subalpine ecosystems in Rocky Mountain National Park may be sensitive to atmospherically derived acidic deposition. Two‐ and three‐component hydrograph separation analyses and correlation analyses were performed for six basins to provide insight into streamflow generation during snowmelt and to assess basin sensitivity to acidic deposition. Three‐component hydrograph separation results for five basins showed that streamflow contained from 42 to 57% direct snowmelt runoff, 37 to 54% subsurface water, and 4 to 13% direct rain runoff for the May through October 1994 study period. Subsurface contributions were 89% of total flow for the sixth basin. The reliability of hydrograph separation model assumptions was explored. Subsurface flow was positively correlated with the amount of surficial material in a basin and was negatively correlated with basin slope. Basins with extensive surficial material and shallow slopes are less susceptible to ecosystem changes due to acidic deposition than basins with less surficial material and steeper slopes. This study was initiated to expand the intensive hydrologic research that has been conducted in Loch Vale basin to a more regional scale.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1999WR900296","usgsCitation":"Suecker, J.K., Ryan, J.N., Kendall, C., and Jarrett, R.D., 2000, Determination of hydrologic pathways during snowmelt for alpine/subalpine basins, Rocky Mountain National Park, Colorado: Water Resources Research, v. 36, no. 1, p. 63-75, https://doi.org/10.1029/1999WR900296.","productDescription":"13 p.","startPage":"63","endPage":"75","costCenters":[],"links":[{"id":487328,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/1999wr900296","text":"Publisher Index Page"},{"id":230767,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffabe4b0c8380cd4f30a","contributors":{"authors":[{"text":"Suecker, Julie K.","contributorId":124572,"corporation":false,"usgs":false,"family":"Suecker","given":"Julie","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":394102,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ryan, Joseph N.","contributorId":54290,"corporation":false,"usgs":false,"family":"Ryan","given":"Joseph","email":"","middleInitial":"N.","affiliations":[{"id":604,"text":"University of Colorado- Boulder","active":false,"usgs":true}],"preferred":false,"id":394103,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kendall, Carol 0000-0002-0247-3405 ckendall@usgs.gov","orcid":"https://orcid.org/0000-0002-0247-3405","contributorId":1462,"corporation":false,"usgs":true,"family":"Kendall","given":"Carol","email":"ckendall@usgs.gov","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":394100,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Jarrett, Robert D. rjarrett@usgs.gov","contributorId":2260,"corporation":false,"usgs":true,"family":"Jarrett","given":"Robert","email":"rjarrett@usgs.gov","middleInitial":"D.","affiliations":[],"preferred":true,"id":394101,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022566,"text":"70022566 - 2000 - Assessment of the photoenhanced toxicity of a weathered oil to the tidewater silverside","interactions":[],"lastModifiedDate":"2016-10-13T12:03:40","indexId":"70022566","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1571,"text":"Environmental Toxicology and Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"Assessment of the photoenhanced toxicity of a weathered oil to the tidewater silverside","docAbstract":"Studies were conducted to determine the interactive toxicity of a water-accommodated fraction (WAF) of a weathered middle distillate petroleum and solar radiation to an estuarine organism, the tidewater silverside (Menidia beryllina). Juvenile silversides were monitored for survival and growth during a 7-d static renewal exposure to dilutions of WAFs of an environmentally weathered oil collected in the vicinity of an abandoned oil field in California. Ultraviolet (UV) treatments were based on incident sunlight intensity and spectra measured at this site. Exposure to UV alone was not lethal to the fish, and WAF in the absence of UV was toxic at the highest total petroleum hydrocarbon (TPH) concentration (3.03 mg/L) after 96 h of exposure. Water-accommodated fractions toxicity increased significantly with increasing UV irradiance and duration of exposure. The 7-d LC50 concentrations for the control, low, medium, and high irradiance were 2.84, 1.27, 0.93, and 0.51 mg/L TPH, respectively. Significant mortality occurred among fish previously exposed to WAF in the absence of irradiance, whereas WAF toxicity was unaffected by UV exposure prior to the toxicity test. Thus, the mode of action is a photosensitization of the accumulated petroleum residue rather than a photoactivation of WAF. Chemical analysis indicates that the WAF contains limited amounts of polycyclic aromatic hydrocarbons (PAHs) known to be photoenhanced, suggesting that other constituents may be responsible for the observed photoenhanced toxicity.
","language":"English","publisher":"Wiley","doi":"10.1002/etc.5620190420","issn":"07307268","usgsCitation":"Little, E.E., Cleveland, L., Calfee, R.D., and Barron, M.G., 2000, Assessment of the photoenhanced toxicity of a weathered oil to the tidewater silverside: Environmental Toxicology and Chemistry, v. 19, no. 4, p. 926-932, https://doi.org/10.1002/etc.5620190420.","productDescription":"7 p.","startPage":"926","endPage":"932","numberOfPages":"7","costCenters":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"links":[{"id":230766,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"19","issue":"4","noUsgsAuthors":false,"publicationDate":"2000-04-01","publicationStatus":"PW","scienceBaseUri":"5059ee66e4b0c8380cd49d38","contributors":{"authors":[{"text":"Little, Edward E. 0000-0003-0034-3639 elittle@usgs.gov","orcid":"https://orcid.org/0000-0003-0034-3639","contributorId":1746,"corporation":false,"usgs":true,"family":"Little","given":"Edward","email":"elittle@usgs.gov","middleInitial":"E.","affiliations":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"preferred":true,"id":394096,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cleveland, Laverne","contributorId":175347,"corporation":false,"usgs":false,"family":"Cleveland","given":"Laverne","email":"","affiliations":[],"preferred":false,"id":394098,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Calfee, Robin D. 0000-0001-6056-7023 rcalfee@usgs.gov","orcid":"https://orcid.org/0000-0001-6056-7023","contributorId":1841,"corporation":false,"usgs":true,"family":"Calfee","given":"Robin","email":"rcalfee@usgs.gov","middleInitial":"D.","affiliations":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"preferred":true,"id":394097,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Barron, Mace G.","contributorId":150751,"corporation":false,"usgs":false,"family":"Barron","given":"Mace","email":"","middleInitial":"G.","affiliations":[{"id":18090,"text":"U.S. Environmental Protection Agency, Gulf Ecology Division, Gulf Breeze, FL","active":true,"usgs":false}],"preferred":false,"id":394099,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022558,"text":"70022558 - 2000 - Composition of fish communities in relation to stream acidification and habitat in the Neversink River, New York","interactions":[],"lastModifiedDate":"2022-07-05T13:32:10.035826","indexId":"70022558","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3624,"text":"Transactions of the American Fisheries Society","active":true,"publicationSubtype":{"id":10}},"title":"Composition of fish communities in relation to stream acidification and habitat in the Neversink River, New York","docAbstract":"The effects of acidification in lotic systems are not well documented. Spatial and temporal variability of habitat and water quality complicate the evaluation of acidification effects in streams and rivers. The Neversink River in the Catskill Mountains of southeastern New York, the tributaries of which vary from well buffered to severely acidified, provided an opportunity to investigate the extent and magnitude of acidification effects on fish communities of headwater systems. Composition of fish communities, water quality, stream hydrology, stream habitat, and physiographic factors were characterized from 1991 to 1995 at 16 first- to fourth-order sites in the basin. Correlation and regression analyses were used to develop empirical models and to assess the relations among fish species richness, total fish density, and total fish biomass and environmental variables. Chronic and episodic acidification and elevated concentrations of inorganic monomeric aluminum were common, and fish populations were rare or absent from several sites in the upper reaches of the basin; as many as six fish species were collected from sites in the lower reaches of the basin. Species distributions and species richness were most highly related to stream pH, acid-neutralizing capacity (ANC), inorganic monomeric aluminum (Alim), calcium (Ca)2+, and potassium (K)+ concentrations, site elevation, watershed drainage area, and water temperature. Fish density was most highly related to stream pH, Alim, ANC, K+, Ca2+, and magnesium (Mg)2+ concentrations. Fish biomass, unlike species richness and fish density, was most highly related to physical habitat characteristics, water temperature, and concentrations of Mg2+ and silicon. Acidity characteristics were of secondary importance to fish biomass at all but the most severely acidified sites. Our results indicate that (1) the total biomass of fish communities was not seriously affected at moderately to strongly acidified sites; (2) species richness and total density of fish were adversely affected at strongly to severely acidified sites; and (3) possible changes in competitive interactions may mitigate negative effects of acidification on fish communities in parts of the Neversink River Basin.
","language":"English","publisher":"American Fisheries Society","doi":"10.1577/1548-8659(2000)129<0060:COFCIR>2.0.CO;2","issn":"00028487","usgsCitation":"Baldigo, B., and Lawrence, G., 2000, Composition of fish communities in relation to stream acidification and habitat in the Neversink River, New York: Transactions of the American Fisheries Society, v. 129, no. 1, p. 60-76, https://doi.org/10.1577/1548-8659(2000)129<0060:COFCIR>2.0.CO;2.","productDescription":"17 p.","startPage":"60","endPage":"76","costCenters":[],"links":[{"id":230655,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"New York","otherGeospatial":"Catskill Mountains, Neversink River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -74.63424682617188,\n 41.87416255688654\n ],\n [\n -74.61708068847656,\n 41.870583462266836\n ],\n [\n -74.5803451538086,\n 41.88617662305848\n ],\n [\n -74.56146240234375,\n 41.914796782203275\n ],\n [\n -74.5037841796875,\n 41.930379151500844\n ],\n [\n -74.47460174560545,\n 41.94953258640636\n ],\n [\n -74.41932678222656,\n 41.95029860413908\n ],\n [\n -74.38362121582031,\n 41.95949009892467\n ],\n [\n -74.41761016845703,\n 42.018947439899584\n ],\n [\n -74.50241088867188,\n 41.99879430655651\n ],\n [\n -74.58549499511719,\n 41.955149836015146\n ],\n [\n -74.59579467773438,\n 41.90304362629451\n ],\n [\n -74.63768005371094,\n 41.88745458227552\n ],\n [\n -74.63424682617188,\n 41.87416255688654\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"129","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f928e4b0c8380cd4d481","contributors":{"authors":[{"text":"Baldigo, Barry P. 0000-0002-9862-9119","orcid":"https://orcid.org/0000-0002-9862-9119","contributorId":25174,"corporation":false,"usgs":true,"family":"Baldigo","given":"Barry P.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":394073,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lawrence, G.B. 0000-0002-8035-2350","orcid":"https://orcid.org/0000-0002-8035-2350","contributorId":76347,"corporation":false,"usgs":true,"family":"Lawrence","given":"G.B.","affiliations":[],"preferred":false,"id":394074,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022548,"text":"70022548 - 2000 - Habitat and landscape correlates of presence, density, and species richness of birds wintering in forest fragments in Ohio","interactions":[],"lastModifiedDate":"2022-08-09T16:29:08.548372","indexId":"70022548","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3783,"text":"The Wilson Bulletin","printIssn":"0043-5643","active":true,"publicationSubtype":{"id":10}},"title":"Habitat and landscape correlates of presence, density, and species richness of birds wintering in forest fragments in Ohio","docAbstract":"We investigated the distribution of wintering woodland bird species in 47 very small, isolated, woodland fragments (0.54-6.01 ha) within an agricultural landscape in north-central Ohio. Our objectives were to determine correlations between temporal, habitat, and landscape variables and avian presence, density, and species richness within the smallest woodlots occupied by such species. Our results suggest that even common species are sensitive to variation in habitat, landscape, and season. Woodlot area explained the most variation in presence, density, and species richness. Shrub cover was also an important predictor variable for presence of the smallest resident birds. Shrub cover might function as both a refuge from predators and as a windbreak, reducing thermal costs in a flat, open landscape. Landscape factors related to isolation and connectedness were also correlated with species presence and density. The species composition of the community changed through the winter, as did the density of individual species, suggesting that the winter season may play an important role in determining the distributions of bird populations across woodlots. The models presented here for Ohio birds in this specific landscape may have biological inference for other species in similar landscapes.","language":"English","publisher":"The Wilson Ornithological Society","doi":"10.1676/0043-5643(2000)112[0388:HALCOP]2.0.CO;2","issn":"00435643","usgsCitation":"Doherty, P.F., and Grubb, T.C., 2000, Habitat and landscape correlates of presence, density, and species richness of birds wintering in forest fragments in Ohio: The Wilson Bulletin, v. 112, no. 3, p. 388-394, https://doi.org/10.1676/0043-5643(2000)112[0388:HALCOP]2.0.CO;2.","productDescription":"7 p.","startPage":"388","endPage":"394","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":479182,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://doi.org/10.1676/0043-5643(2000)112[0388:halcop]2.0.co;2","text":"External Repository"},{"id":230507,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Ohio","county":"Crawford County, Delaware County, Marion County, Morrow County","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"Polygon\",\"coordinates\":[[[-82.8292,40.9967],[-82.8049,40.9968],[-82.7964,40.9963],[-82.73,40.996],[-82.7245,40.996],[-82.7245,40.982],[-82.7244,40.9647],[-82.7247,40.8749],[-82.7273,40.7112],[-82.6272,40.7095],[-82.6272,40.6873],[-82.6259,40.6664],[-82.6386,40.6664],[-82.6447,40.6664],[-82.6447,40.6632],[-82.6447,40.66],[-82.6447,40.6373],[-82.6247,40.6374],[-82.6252,40.6247],[-82.624,40.5866],[-82.6239,40.568],[-82.6239,40.5671],[-82.6233,40.5503],[-82.6433,40.5503],[-82.6432,40.5222],[-82.6341,40.5231],[-82.6329,40.5217],[-82.6465,40.3448],[-82.6899,40.347],[-82.6953,40.347],[-82.711,40.3479],[-82.7448,40.3497],[-82.7494,40.2916],[-82.7506,40.2771],[-82.754,40.2272],[-82.7621,40.1256],[-82.9383,40.1338],[-83.0677,40.1382],[-83.17,40.1427],[-83.1721,40.2438],[-83.248,40.2448],[-83.2481,40.3676],[-83.2501,40.3821],[-83.2483,40.4438],[-83.2484,40.5069],[-83.4188,40.5053],[-83.4148,40.5153],[-83.4169,40.5443],[-83.4177,40.5561],[-83.4185,40.5692],[-83.4201,40.6001],[-83.4203,40.6146],[-83.42,40.6436],[-83.42,40.6872],[-83.3812,40.6874],[-83.3133,40.6874],[-83.3048,40.687],[-83.305,40.702],[-83.2983,40.702],[-83.2468,40.7028],[-83.2262,40.7025],[-83.1928,40.7022],[-83.1686,40.7023],[-83.1619,40.7024],[-83.1595,40.7024],[-83.111,40.7031],[-83.1121,40.9721],[-83.1129,40.9934],[-83.0739,40.9936],[-83.0587,40.9941],[-83.0551,40.9941],[-83.035,40.9938],[-82.9187,40.9937],[-82.9011,40.9938],[-82.8603,40.9935],[-82.8536,40.9939],[-82.853,40.9971],[-82.842,40.9967],[-82.8347,40.9972],[-82.8292,40.9967]]]},\"properties\":{\"name\":\"Crawford\",\"state\":\"OH\"}}]}","volume":"112","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2ef2e4b0c8380cd5c969","contributors":{"authors":[{"text":"Doherty, Paul F. Jr.","contributorId":37636,"corporation":false,"usgs":false,"family":"Doherty","given":"Paul","suffix":"Jr.","email":"","middleInitial":"F.","affiliations":[{"id":6621,"text":"Colorado State University","active":true,"usgs":false}],"preferred":false,"id":394035,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Grubb, Thomas C. Jr.","contributorId":73774,"corporation":false,"usgs":true,"family":"Grubb","given":"Thomas","suffix":"Jr.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":394034,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022547,"text":"70022547 - 2000 - Classification methods for monitoring Arctic sea ice using OKEAN passive/active two-channel microwave data","interactions":[],"lastModifiedDate":"2013-12-03T16:00:41","indexId":"70022547","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3254,"text":"Remote Sensing of Environment","printIssn":"0034-4257","active":true,"publicationSubtype":{"id":10}},"title":"Classification methods for monitoring Arctic sea ice using OKEAN passive/active two-channel microwave data","docAbstract":"This paper presents methods for classifying Arctic sea ice using both passive and active (2-channel) microwave imagery acquired by the Russian OKEAN 01 polar-orbiting satellite series. Methods and results are compared to sea ice classifications derived from nearly coincident Special Sensor Microwave Imager (SSM/I) and Advanced Very High Resolution Radiometer (AVHRR) image data of the Barents, Kara, and Laptev Seas. The Russian OKEAN 01 satellite data were collected over weekly intervals during October 1995 through December 1997. Methods are presented for calibrating, georeferencing and classifying the raw active radar and passive microwave OKEAN 01 data, and for correcting the OKEAN 01 microwave radiometer calibration wedge based on concurrent 37 GHz horizontal polarization SSM/I brightness temperature data. Sea ice type and ice concentration algorithms utilized OKEAN's two-channel radar and passive microwave data in a linear mixture model based on the measured values of brightness temperature and radar backscatter, together with a priori knowledge about the scattering parameters and natural emissivities of basic sea ice types. OKEAN 01 data and algorithms tended to classify lower concentrations of young or first-year sea ice when concentrations were less than 60%, and to produce higher concentrations of multi-year sea ice when concentrations were greater than 40%, when compared to estimates produced from SSM/I data. Overall, total sea ice concentration maps derived independently from OKEAN 01, SSM/I, and AVHRR satellite imagery were all highly correlated, with uniform biases, and mean differences in total ice concentration of less than four percent (sd<15%).","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Remote Sensing of Environment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Science Inc","publisherLocation":"New York, NY, United States","doi":"10.1016/S0034-4257(00)00107-3","issn":"00344257","usgsCitation":"Belchansky, G.I., and Douglas, D.C., 2000, Classification methods for monitoring Arctic sea ice using OKEAN passive/active two-channel microwave data: Remote Sensing of Environment, v. 73, no. 3, p. 307-322, https://doi.org/10.1016/S0034-4257(00)00107-3.","startPage":"307","endPage":"322","numberOfPages":"16","costCenters":[],"links":[{"id":206669,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0034-4257(00)00107-3"},{"id":230506,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"73","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f617e4b0c8380cd4c5b1","contributors":{"authors":[{"text":"Belchansky, Gennady I.","contributorId":71471,"corporation":false,"usgs":true,"family":"Belchansky","given":"Gennady","email":"","middleInitial":"I.","affiliations":[],"preferred":false,"id":394033,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Douglas, David C. 0000-0003-0186-1104 ddouglas@usgs.gov","orcid":"https://orcid.org/0000-0003-0186-1104","contributorId":2388,"corporation":false,"usgs":true,"family":"Douglas","given":"David","email":"ddouglas@usgs.gov","middleInitial":"C.","affiliations":[{"id":116,"text":"Alaska Science Center Biology MFEB","active":true,"usgs":true}],"preferred":true,"id":394032,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022536,"text":"70022536 - 2000 - Uncertain nest fates in songbird studies and variation in Mayfield estimation","interactions":[],"lastModifiedDate":"2017-05-09T16:03:34","indexId":"70022536","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3544,"text":"The Auk","onlineIssn":"1938-4254","printIssn":"0004-8038","active":true,"publicationSubtype":{"id":10}},"title":"Uncertain nest fates in songbird studies and variation in Mayfield estimation","docAbstract":"Determining whether nesting attempts are successful can be difficult. Yet, current protocols for estimating nesting success do not address how uncertain nest fates should be handled. We examined the problem of nest-fate uncertainty as it relates to Mayfield estimation of nesting success and in analyses of factors that influence success. We used data from Minnesota to illustrate the potential effect of uncertain fate; 40% of Ovenbird (Seiurus aurocapillus; n = 127) nests and 30% of Least Flycatcher (Empidonax minimus; n = 144) nests had uncertain fates. How this uncertainty is incorporated into Mayfield estimates of success varied widely among researchers. In a survey of researchers who use the Mayfield method, 9 of 22 respondents (of 40 contacted) excluded nests with uncertain fate. Excluding uncertain fates is counter to how Mayfield first described his estimator and can result in severe downward bias. The remaining respondents (59%) included nests with uncertain fate but varied in how they terminated the exposure period. We developed a simulation model that calculated Mayfield estimates using different approaches and compared them with a known rate of nesting success. Magnitude of bias in Mayfield estimates varied considerably in our simulations. The approach with the least bias terminated exposure with the last observed active date for nests with uncertain fate, and with the midpoint between last observed active and first observed inactive dates for nests with known fate. In addition, information necessary to interpret and compare Mayfield estimates often is not reported. These values, including variance estimates and the period lengths used to estimate survival rates, should be reported with Mayfield estimates. Finally, nest fate is commonly used as a categorical variable in studies of factors affecting nesting success. In this approach, however, nests with uncertain fate must be excluded. An alternative approach is Cox regression, which incorporates nests with uncertain fate.","language":"English","publisher":"American Ornithological Society","doi":"10.1642/0004-8038(2000)117[0615:UNFISS]2.0.CO;2","issn":"00048038","usgsCitation":"Manolis, J., Andersen, D., and Cuthbert, F., 2000, Uncertain nest fates in songbird studies and variation in Mayfield estimation: The Auk, v. 117, no. 3, p. 615-626, https://doi.org/10.1642/0004-8038(2000)117[0615:UNFISS]2.0.CO;2.","productDescription":"12 p.","startPage":"615","endPage":"626","costCenters":[],"links":[{"id":479173,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1642/0004-8038(2000)117[0615:unfiss]2.0.co;2","text":"Publisher Index Page"},{"id":230313,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"117","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bbc13e4b08c986b328a03","contributors":{"authors":[{"text":"Manolis, J.C.","contributorId":7133,"corporation":false,"usgs":true,"family":"Manolis","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":393980,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Andersen, D. E.","contributorId":27816,"corporation":false,"usgs":true,"family":"Andersen","given":"D. E.","affiliations":[],"preferred":false,"id":393981,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cuthbert, F.J.","contributorId":45272,"corporation":false,"usgs":true,"family":"Cuthbert","given":"F.J.","email":"","affiliations":[],"preferred":false,"id":393982,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022533,"text":"70022533 - 2000 - Quantifying time-varying ground-water discharge and recharge in wetlands of the northern Florida Everglades","interactions":[],"lastModifiedDate":"2022-06-27T18:25:20.543025","indexId":"70022533","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3750,"text":"Wetlands","onlineIssn":"1943-6246","printIssn":"0277-5212","active":true,"publicationSubtype":{"id":10}},"title":"Quantifying time-varying ground-water discharge and recharge in wetlands of the northern Florida Everglades","docAbstract":"Developing a more thorough understanding of water and chemical budgets in wetlands depends in part on our ability to quantify time-varying interactions between ground water and surface water. We used a combined water and solute mass balance approach to estimate time-varying ground-water discharge and recharge in the Everglades Nutrient Removal project (ENR), a relatively large constructed wetland (1544 hectare) built for removing nutrients from agricultural drainage in the northern Everglades in South Florida, USA. Over a 4-year period (1994 through 1998), ground-water recharge averaged 13.4 hectare-meter per day (ha-m/day) or 0.9 cm/day, which is approximately 31% of surface water pumped into the ENR for treatment. In contrast, ground-water discharge was much smaller (1.4 ha-m/day, or 0.09 cm/day, or 2.8% of water input to ENR for treatment). Using a water-balance approach alone only allowed net ground-water exchange (discharge — recharge) to be estimated (−12±2.4 ha-m/day). Discharge and recharge were individually determined by combining a chloride mass balance with the water balance. For a variety of reasons, the ground-water discharge estimated by the combined mass balance approach was not reliable (1.4±37 ha-m/day). As a result, ground-water interactions could only be reliably estimated by comparing the mass-balance results with other independent approaches, including direct seepage-meter measurements and previous estimates using ground-water modeling. All three independent approaches provided similar estimates of average ground-water recharge, ranging from 13 to 14 ha-m/day. There was also relatively good agreement between ground-water discharge estimates for the mass balance and seepage meter methods, 1.4 and 0.9 ha-m/day, respectively. However, ground-water-flow modeling provided an average discharge estimate that was approximately a factor of four higher (5.4 ha-m/day) than the other two methods. Our study developed an initial understanding of how the design and operation of the ENR increases interactions between ground water and surface water. A considerable portion of recharged ground water (73%) was collected and returned to the ENR by a seepage canal. Additional recharge that was not captured by the seepage canal only occurred when pumped inflow rates to ENR (and ENR water levels) were relatively high. Management of surface water in the northern Everglades therefore clearly has the potential to increase interactions with ground water.
","language":"English","publisher":"Springer","doi":"10.1672/0277-5212(2000)020<0500:QTGDAR>2.0.CO;2","issn":"02775212","usgsCitation":"Choi, J., and Harvey, J.W., 2000, Quantifying time-varying ground-water discharge and recharge in wetlands of the northern Florida Everglades: Wetlands, v. 20, no. 3, p. 500-511, https://doi.org/10.1672/0277-5212(2000)020<0500:QTGDAR>2.0.CO;2.","productDescription":"12 p.","startPage":"500","endPage":"511","costCenters":[],"links":[{"id":230879,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Everglades","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -80.82366943359375,\n 26.290952564755845\n ],\n [\n -80.10406494140625,\n 26.290952564755845\n ],\n [\n -80.10406494140625,\n 26.924518806384913\n ],\n [\n -80.82366943359375,\n 26.924518806384913\n ],\n [\n -80.82366943359375,\n 26.290952564755845\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"20","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a91eee4b0c8380cd80553","contributors":{"authors":[{"text":"Choi, Jungyill","contributorId":70792,"corporation":false,"usgs":true,"family":"Choi","given":"Jungyill","email":"","affiliations":[],"preferred":false,"id":393975,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Harvey, Judson W. 0000-0002-2654-9873 jwharvey@usgs.gov","orcid":"https://orcid.org/0000-0002-2654-9873","contributorId":1796,"corporation":false,"usgs":true,"family":"Harvey","given":"Judson","email":"jwharvey@usgs.gov","middleInitial":"W.","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":393974,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022530,"text":"70022530 - 2000 - Adsorption and fractionation of a muck fulvic acid on kaolinite and goethite at pH 3.7,6, and 8","interactions":[],"lastModifiedDate":"2022-08-10T17:58:56.0452","indexId":"70022530","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3419,"text":"Soil Science","active":true,"publicationSubtype":{"id":10}},"title":"Adsorption and fractionation of a muck fulvic acid on kaolinite and goethite at pH 3.7,6, and 8","docAbstract":"Molecular weight (MW) of humic materials is a key factor controlling proton and metal binding and organic pollutant partitioning. Several studies have suggested preferential adsorption of higher MW, more aromatic moieties to mineral surfaces; quantification of such processes is fundamental to development of predictive models. We used high pressure size exclusion chromatography (HPSEC) to quantify MW changes upon adsorption of a muck fulvic acid (MFA) extracted from a peat deposit to kaolinite and goethite, at pH 3.7, 6, and 8 at 22 °C, I = 0.01 (NaCl), 24-h reaction time. MFA adsorption affinity was greater for goethite than for kaolinite. At concentrations less than the adsorption maximum (Amax) for both adsorbents, the weight-average MW (Mw) of MFA remaining in solution decreased by as much as several hundred Daltons relative to control samples, indicating preferential adsorption of the higher MW components. At concentrations more than Amax, Mw of MFA in solution did not change appreciably. Although total adsorption decreased significantly as pH increased, fractionation as measured by change in Mw remained similar, perhaps indicating greater selectivity for higher MW components at higher pH.
Absorptivities at λ = 280 nm normalized to mg C L−1 (ε) suggested preferential adsorption of more aromatic moieties to kaolinite. ε could not be used for goethite-reacted samples because high Fe concentrations in the aqueous phase brought about by goethite dissolution interfered with the spectroscopic analysis. Preliminary kinetic experiments suggested that smaller molecules adsorbed first and were replaced by larger molecules whose adsorption was thermodynamically favored.
","language":"English","publisher":"Wolters Kluwer","issn":"0038075X","usgsCitation":"Namjesnik-Dejanovic, K., Maurice, P., Aiken, G., Cabaniss, S., Chin, Y., and Pullin, M., 2000, Adsorption and fractionation of a muck fulvic acid on kaolinite and goethite at pH 3.7,6, and 8: Soil Science, v. 165, no. 7, p. 545-559.","productDescription":"15 p.","startPage":"545","endPage":"559","costCenters":[],"links":[{"id":230839,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":405086,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://journals.lww.com/soilsci/Abstract/2000/07000/ADSORPTION_AND_FRACTIONATION_OF_A_MUCK_FULVIC_ACID.3.aspx"}],"volume":"165","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e6fbe4b0c8380cd4777b","contributors":{"authors":[{"text":"Namjesnik-Dejanovic, K.","contributorId":30389,"corporation":false,"usgs":true,"family":"Namjesnik-Dejanovic","given":"K.","email":"","affiliations":[],"preferred":false,"id":393960,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Maurice, P.A.","contributorId":48336,"corporation":false,"usgs":true,"family":"Maurice","given":"P.A.","email":"","affiliations":[],"preferred":false,"id":393961,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Aiken, G. R. 0000-0001-8454-0984","orcid":"https://orcid.org/0000-0001-8454-0984","contributorId":14452,"corporation":false,"usgs":true,"family":"Aiken","given":"G. R.","affiliations":[],"preferred":false,"id":393959,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Cabaniss, S.","contributorId":88906,"corporation":false,"usgs":true,"family":"Cabaniss","given":"S.","email":"","affiliations":[],"preferred":false,"id":393963,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Chin, Y.-P.","contributorId":84911,"corporation":false,"usgs":true,"family":"Chin","given":"Y.-P.","email":"","affiliations":[],"preferred":false,"id":393962,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Pullin, M.J.","contributorId":93235,"corporation":false,"usgs":true,"family":"Pullin","given":"M.J.","email":"","affiliations":[],"preferred":false,"id":393964,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70022528,"text":"70022528 - 2000 - Growth and food consumption by tiger muskellunge: Effects of temperature and ration level on bioenergetic model predictions","interactions":[],"lastModifiedDate":"2022-06-29T20:50:11.246525","indexId":"70022528","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3624,"text":"Transactions of the American Fisheries Society","active":true,"publicationSubtype":{"id":10}},"title":"Growth and food consumption by tiger muskellunge: Effects of temperature and ration level on bioenergetic model predictions","docAbstract":"We measured growth of age-0 tiger muskellunge as a function of ration size (25, 50, 75, and 100% Cmax) and water temperature (7.5–25°C) and compared experimental results with those predicted from a bioenergetic model. Discrepancies between actual and predicted values varied appreciably with water temperature and growth rate. On average, model output overestimated winter consumption rates at 10 and 7.5°C by 113 to 328%, respectively, whereas model predictions in summer and autumn (20–25°C) were in better agreement with actual values (4 to 58%). We postulate that variation in model performance was related to seasonal changes in esocid metabolic rate, which were not accounted for in the bioenergetic model. Moreover, accuracy of model output varied with feeding and growth rate of tiger muskellunge. The model performed poorly for fish fed low rations compared with estimates based on fish fed ad libitum rations and was attributed, in part, to the influence of growth rate on the accuracy of bioenergetic predictions. Based on modeling simulations, we found that errors associated with bioenergetic parameters had more influence on model output when growth rate was low, which is consistent with our observations. In addition, reduced conversion efficiency at high ration levels may contribute to variable model performance, thereby implying that waste losses should be modeled as a function of ration size for esocids. Our findings support earlier field tests of the esocid bioenergetic model and indicate that food consumption is generally overestimated by the model, particularly in winter months and for fish exhibiting low feeding and growth rates.
","language":"English","publisher":"Wiley","doi":"10.1577/1548-8659(2000)129<0186:GAFCBT>2.0.CO;2","issn":"00028487","usgsCitation":"Chipps, S.R., Einfalt, L.M., and Wahl, D., 2000, Growth and food consumption by tiger muskellunge: Effects of temperature and ration level on bioenergetic model predictions: Transactions of the American Fisheries Society, v. 129, no. 1, p. 186-193, https://doi.org/10.1577/1548-8659(2000)129<0186:GAFCBT>2.0.CO;2.","productDescription":"8 p.","startPage":"186","endPage":"193","costCenters":[],"links":[{"id":230803,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"129","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2de4e4b0c8380cd5c0fd","contributors":{"authors":[{"text":"Chipps, Steven R. 0000-0001-6511-7582 steve_chipps@usgs.gov","orcid":"https://orcid.org/0000-0001-6511-7582","contributorId":2243,"corporation":false,"usgs":true,"family":"Chipps","given":"Steven","email":"steve_chipps@usgs.gov","middleInitial":"R.","affiliations":[{"id":199,"text":"Coop Res Unit Leetown","active":true,"usgs":true}],"preferred":true,"id":393952,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Einfalt, Lisa M.","contributorId":62784,"corporation":false,"usgs":true,"family":"Einfalt","given":"Lisa","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":393953,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Wahl, David H.","contributorId":85532,"corporation":false,"usgs":true,"family":"Wahl","given":"David H.","affiliations":[],"preferred":false,"id":393954,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022525,"text":"70022525 - 2000 - Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations","interactions":[],"lastModifiedDate":"2013-10-29T11:43:45","indexId":"70022525","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations","docAbstract":"Paleomagnetic and geochronologic data combined with geologic mapping tightly restrict the timing and character of a late Oligocene to early Miocene episode of large magnitude extension in the southern Stillwater Range and adjacent regions of west central Nevada. The southern Stillwater Range was the site of an Oligocene to early Miocene volcanic center comprising (1) 28.3 to 24.3 Ma intracaldera ash flow tuffs, lava flows, and subjacent plutons associated with three calderas, (2) 24.8 to 20.7 Ma postcaldera silicic dikes and domes, and (3) unconformably overlying 15.3 to 13.0 Ma dacite to basalt lava flows, plugs, and dikes. The caldera-related tuffs, lava flows, and plutons were tilted 60°-70° either west or east during the initial period of Cenozoic deformation that accommodated over 100% extension. Directions of remanent magnetization obtained from these extrusive and intrusive, caldera-related rocks are strongly deflected from an expected Miocene direction in senses appropriate for their tilt. A mean direction for these rocks after tilt correction, however, suggests that they were also affected by a moderate (33.4° ± 11.8°) component of counterclockwise vertical axis rotation. Paleomagnetic data indicate that the episode of large tilting occurred during emplacement of 24.8 to 20.7 Ma postcaldera dikes and domes. In detail, an apparent decrease in rotation with decreasing age of individual, isotopically dated bodies of the postcaldera group indicates that most tilting occurred between 24.4 and 24.2 Ma. The onset of tilting immediately following after the final caldera eruptions suggests that the magmatism and deformation were linked. Deformation was not driven by magma buoyancy, however, because tilting equally affected the caldera systems of different ages, including their plutonic roots. It is more likely that regional extension was focused in the southern Stillwater Range due to magmatic warming and reduction of tensile strength of the brittle crust. Faults that accommodated deformation in the southern Stillwater Range initially dipped steeply and cut deeply to expose more than 9 km of crustal section. The exposed crustal sections are probably rotated blocks above an unexposed basal detachment that lay near the early Miocene brittle-ductile transition.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Geophysical Research B: Solid Earth","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/1999JB900338","issn":"01480227","usgsCitation":"Hudson, M., John, D.A., Conrad, J.E., and McKee, E.H., 2000, Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations: Journal of Geophysical Research B: Solid Earth, v. 105, no. B1, p. 929-954, https://doi.org/10.1029/1999JB900338.","startPage":"929","endPage":"954","numberOfPages":"26","costCenters":[],"links":[{"id":479288,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/1999jb900338","text":"Publisher Index Page"},{"id":230763,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":278525,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/1999JB900338"}],"volume":"105","issue":"B1","noUsgsAuthors":false,"publicationDate":"2000-01-10","publicationStatus":"PW","scienceBaseUri":"505b9cf0e4b08c986b31d53e","contributors":{"authors":[{"text":"Hudson, Mark R. 0000-0003-0338-6079 mhudson@usgs.gov","orcid":"https://orcid.org/0000-0003-0338-6079","contributorId":1236,"corporation":false,"usgs":true,"family":"Hudson","given":"Mark R.","email":"mhudson@usgs.gov","affiliations":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"preferred":true,"id":393942,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"John, David A. 0000-0001-7977-9106 djohn@usgs.gov","orcid":"https://orcid.org/0000-0001-7977-9106","contributorId":1748,"corporation":false,"usgs":true,"family":"John","given":"David","email":"djohn@usgs.gov","middleInitial":"A.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":true,"id":393943,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Conrad, James E. 0000-0001-6655-694X jconrad@usgs.gov","orcid":"https://orcid.org/0000-0001-6655-694X","contributorId":2316,"corporation":false,"usgs":true,"family":"Conrad","given":"James","email":"jconrad@usgs.gov","middleInitial":"E.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":393944,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McKee, Edwin H. mckee@usgs.gov","contributorId":3728,"corporation":false,"usgs":true,"family":"McKee","given":"Edwin","email":"mckee@usgs.gov","middleInitial":"H.","affiliations":[],"preferred":true,"id":393945,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022519,"text":"70022519 - 2000 - 10,000 Years of explosive eruptions of Merapi Volcano, Central Java: archaeological and modern implications","interactions":[],"lastModifiedDate":"2013-12-03T12:36:34","indexId":"70022519","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2499,"text":"Journal of Volcanology and Geothermal Research","active":true,"publicationSubtype":{"id":10}},"title":"10,000 Years of explosive eruptions of Merapi Volcano, Central Java: archaeological and modern implications","docAbstract":"Stratigraphy and radiocarbon dating of pyroclastic deposits at Merapi Volcano, Central Java, reveals ~10,000 years of explosive eruptions. Highlights include:
\n(1) Construction of an Old Merapi stratovolcano to the height of the present cone or slightly higher. Our oldest age for an explosive eruption is 9630±60 14C y B.P.; construction of Old Merapi certainly began earlier.
\n(2) Collapse(s) of Old Merapi that left a somma rim high on its eastern slope and sent one or more debris avalanche(s) down its southern and western flanks. Impoundment of Kali Progo to form an early Lake Borobudur at ~3400 14C y B.P. hints at a possible early collapse of Merapi. The latest somma-forming collapse occurred ~1900 14C y B.P. The current cone, New Merapi, began to grow soon thereafter.
\n(3) Several large and many small Buddhist and Hindu temples were constructed in Central Java between 732 and ~900 A.D. (roughly, 1400-1000 14C y B.P.). Explosive Merapi eruptions occurred before, during and after temple construction. Some temples were destroyed and (or) buried soon after their construction, and we suspect that this destruction contributed to an abrupt shift of power and organized society to East Java in 928 A.D. Other temples sites, though, were occupied by \"caretakers\" for several centuries longer.
\n(4) A partial collapse of New Merapi occurred <1130±50 14C y B.P. Eruptions ~700-800 14C y B.P. (12-14th century A.D.) deposited ash on the floors of (still-occupied?) Candi Sambisari and Candi Kedulan. We speculate but cannot prove that these eruptions were triggered by (the same?) partial collapse of New Merapi, and that the eruptions, in turn, ended \"caretaker\" occupation at Candi Sambisari and Candi Kedulan. A new or raised Lake Borobudur also existed during part or all of the 12-14th centuries, probably impounded by deposits from Merapi.
\n(5) Relatively benign lava-dome extrusion and dome-collapse pyroclastic flows have dominated activity of the 20th century, but explosive eruptions much larger than any of this century have occurred many times during Merapi's history, most recently during the 19th century.
\nAre the relatively small eruptions of the 20th century a new style of open-vent, less hazardous activity that will persist for the foreseeable future? Or, alternatively, are they merely low-level \"background\" activity that could be interrupted upon relatively short notice by much larger explosive eruptions? The geologic record suggests the latter, which would place several hundred thousand people at risk. We know of no reliable method to forecast when an explosive eruption will interrupt the present interval of low-level activity. This conclusion has important implications for hazard evaluation.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Volcanology and Geothermal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0377-0273(00)00132-3","issn":"03770273","usgsCitation":"Newhall, C.G., Bronto, S., Alloway, B., Banks, N., Bahar, I., Marmol, D., Hadisantono, R., Holcomb, R.T., McGeehin, J., Miksic, J., Rubin, M., Sayudi, S., Sukhyar, R., Andreastuti, S., Tilling, R., Torley, R., Trimble, D., and Wirakusumah, A., 2000, 10,000 Years of explosive eruptions of Merapi Volcano, Central Java: archaeological and modern implications: Journal of Volcanology and Geothermal Research, v. 100, no. 1-4, p. 9-50, https://doi.org/10.1016/S0377-0273(00)00132-3.","startPage":"9","endPage":"50","numberOfPages":"42","costCenters":[],"links":[{"id":230685,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":280148,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0377-0273(00)00132-3"}],"volume":"100","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e220e4b0c8380cd45995","contributors":{"authors":[{"text":"Newhall, C. G.","contributorId":93056,"corporation":false,"usgs":true,"family":"Newhall","given":"C.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":393917,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bronto, S.","contributorId":65633,"corporation":false,"usgs":true,"family":"Bronto","given":"S.","email":"","affiliations":[],"preferred":false,"id":393912,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Alloway, B.","contributorId":11367,"corporation":false,"usgs":true,"family":"Alloway","given":"B.","affiliations":[],"preferred":false,"id":393903,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Banks, N.G.","contributorId":60635,"corporation":false,"usgs":true,"family":"Banks","given":"N.G.","email":"","affiliations":[],"preferred":false,"id":393910,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Bahar, I.","contributorId":51492,"corporation":false,"usgs":true,"family":"Bahar","given":"I.","email":"","affiliations":[],"preferred":false,"id":393909,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Marmol, Del","contributorId":16184,"corporation":false,"usgs":true,"family":"Marmol","given":"Del","email":"","affiliations":[],"preferred":false,"id":393904,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Hadisantono, R.D.","contributorId":61056,"corporation":false,"usgs":true,"family":"Hadisantono","given":"R.D.","email":"","affiliations":[],"preferred":false,"id":393911,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Holcomb, R. T.","contributorId":99146,"corporation":false,"usgs":true,"family":"Holcomb","given":"R.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":393919,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"McGeehin, J.","contributorId":49554,"corporation":false,"usgs":true,"family":"McGeehin","given":"J.","email":"","affiliations":[],"preferred":false,"id":393908,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Miksic, J.N.","contributorId":103029,"corporation":false,"usgs":true,"family":"Miksic","given":"J.N.","email":"","affiliations":[],"preferred":false,"id":393920,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Rubin, M.","contributorId":88079,"corporation":false,"usgs":true,"family":"Rubin","given":"M.","email":"","affiliations":[],"preferred":false,"id":393916,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Sayudi, S.D.","contributorId":86519,"corporation":false,"usgs":true,"family":"Sayudi","given":"S.D.","email":"","affiliations":[],"preferred":false,"id":393915,"contributorType":{"id":1,"text":"Authors"},"rank":12},{"text":"Sukhyar, R.","contributorId":19326,"corporation":false,"usgs":true,"family":"Sukhyar","given":"R.","email":"","affiliations":[],"preferred":false,"id":393905,"contributorType":{"id":1,"text":"Authors"},"rank":13},{"text":"Andreastuti, Supriyati","contributorId":82087,"corporation":false,"usgs":true,"family":"Andreastuti","given":"Supriyati","email":"","affiliations":[],"preferred":false,"id":393914,"contributorType":{"id":1,"text":"Authors"},"rank":14},{"text":"Tilling, R.I. 0000-0003-4263-7221","orcid":"https://orcid.org/0000-0003-4263-7221","contributorId":98311,"corporation":false,"usgs":true,"family":"Tilling","given":"R.I.","affiliations":[],"preferred":false,"id":393918,"contributorType":{"id":1,"text":"Authors"},"rank":15},{"text":"Torley, R.","contributorId":37106,"corporation":false,"usgs":true,"family":"Torley","given":"R.","email":"","affiliations":[],"preferred":false,"id":393907,"contributorType":{"id":1,"text":"Authors"},"rank":16},{"text":"Trimble, D.","contributorId":22934,"corporation":false,"usgs":true,"family":"Trimble","given":"D.","affiliations":[],"preferred":false,"id":393906,"contributorType":{"id":1,"text":"Authors"},"rank":17},{"text":"Wirakusumah, A.D.","contributorId":77321,"corporation":false,"usgs":true,"family":"Wirakusumah","given":"A.D.","email":"","affiliations":[],"preferred":false,"id":393913,"contributorType":{"id":1,"text":"Authors"},"rank":18}]}} ,{"id":70022518,"text":"70022518 - 2000 - Data report: Mid-Pliocene diatom assemblages at sites 1016, 1021, and 1022","interactions":[],"lastModifiedDate":"2018-03-02T14:57:48","indexId":"70022518","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":3,"text":"Organization Series"},"seriesTitle":{"id":5640,"text":"Proceedings of the Ocean Drilling Program: Scientific Results","onlineIssn":"1096-7451","printIssn":"0884-5891","active":true,"publicationSubtype":{"id":3}},"seriesNumber":"167","chapter":"4","title":"Data report: Mid-Pliocene diatom assemblages at sites 1016, 1021, and 1022","docAbstract":"Diatom assemblages from the middle part of the Pliocene (3.2-2.5 Ma) were investigated from Ocean Drilling Program Sites 1016, 1021, and 1022 in an effort to infer paleotemperature fluctuations off California.
Diatoms are very sparse in virtually all of the samples that were examined from Sites 1016 and 1021. This is presumably because these sites were seaward (west) of the coastal zone of diatom productivity during the middle part of the Pliocene.
Diatoms are relatively common in the vast majority of samples that were examined from Hole 1022A. Diatom assemblages are dominated by Chaetoceros spores (a coastal upwelling component), the cold-water (subarctic) taxa Neodenticula kamtschatica and its descendant Neodenticula koizumii, and Thalassionema nitzschioides, a temperate taxon that is typically found at the seaward edge of coastal upwelling zones. Paleotemperature interpretations, however, are not possible at this time because of the scarcity of comparative modern core-top data.
","language":"English","publisher":"Ocean Drilling Program, Texas A&M University","publisherLocation":"College Station, TX","doi":"10.2973/odp.proc.sr.167.226.2000","usgsCitation":"Barron, J.A., 2000, Data report: Mid-Pliocene diatom assemblages at sites 1016, 1021, and 1022: Proceedings of the Ocean Drilling Program: Scientific Results 167, v. 167, 3 p., https://doi.org/10.2973/odp.proc.sr.167.226.2000.","productDescription":"3 p.","startPage":"111","endPage":"113","costCenters":[],"links":[{"id":230653,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"167","publicComments":"Volume topic: California Margin: covering Leg 167 of the cruises of the Drilling Vessel JOIDES Resolution, Acapulco, Mexico, to San Francisco, California, Sites 1010-1022, 20 April-16 June 1996","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fdb5e4b0c8380cd4e92c","contributors":{"editors":[{"text":"Nessler, Susan","contributorId":56548,"corporation":false,"usgs":false,"family":"Nessler","given":"Susan","email":"","affiliations":[],"preferred":false,"id":730030,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Miller, Christine M.","contributorId":189442,"corporation":false,"usgs":false,"family":"Miller","given":"Christine","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":730031,"contributorType":{"id":2,"text":"Editors"},"rank":2},{"text":"Peters, Lori L.","contributorId":38141,"corporation":false,"usgs":false,"family":"Peters","given":"Lori","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":730032,"contributorType":{"id":2,"text":"Editors"},"rank":3}],"authors":[{"text":"Barron, John A. 0000-0002-9309-1145 jbarron@usgs.gov","orcid":"https://orcid.org/0000-0002-9309-1145","contributorId":2222,"corporation":false,"usgs":true,"family":"Barron","given":"John","email":"jbarron@usgs.gov","middleInitial":"A.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":393902,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022517,"text":"70022517 - 2000 - Gap analysis: Concepts, methods, and recent results","interactions":[],"lastModifiedDate":"2012-03-12T17:19:44","indexId":"70022517","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2602,"text":"Landscape Ecology","active":true,"publicationSubtype":{"id":10}},"title":"Gap analysis: Concepts, methods, and recent results","docAbstract":"Rapid progress is being made in the conceptual, technical, and organizational requirements for generating synoptic multi-scale views of the earth's surface and its biological content. Using the spatially comprehensive data that are now available, researchers, land managers, and land-use planners can, for the first time, quantitatively place landscape units - from general categories such as 'Forests' or 'Cold-Deciduous Shrubland Formation' to more categories such as 'Picea glauca-Abies balsamea-Populus spp. Forest Alliance' - in their large-area contexts. The National Gap Analysis Program (GAP) has developed the technical and organizational capabilities necessary for the regular production and analysis of such information. This paper provides a brief overview of concepts and methods as well as some recent results from the GAP projects. Clearly, new frameworks for biogeographic information and organizational cooperation are needed if we are to have any hope of documenting the full range of species occurrences and ecological processes in ways meaningful to their management. The GAP experience provides one model for achieving these new frameworks.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Landscape Ecology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/A:1008184408300","issn":"09212973","usgsCitation":"Jennings, M., 2000, Gap analysis: Concepts, methods, and recent results: Landscape Ecology, v. 15, no. 1, p. 5-20, https://doi.org/10.1023/A:1008184408300.","startPage":"5","endPage":"20","numberOfPages":"16","costCenters":[],"links":[{"id":206732,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1008184408300"},{"id":230652,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a14b6e4b0c8380cd54b21","contributors":{"authors":[{"text":"Jennings, M.D.","contributorId":53976,"corporation":false,"usgs":true,"family":"Jennings","given":"M.D.","email":"","affiliations":[],"preferred":false,"id":393901,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022515,"text":"70022515 - 2000 - Growth response of a deep-water ferromanganese crust to evolution of the Neogene Indian Ocean","interactions":[],"lastModifiedDate":"2012-03-12T17:19:44","indexId":"70022515","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Growth response of a deep-water ferromanganese crust to evolution of the Neogene Indian Ocean","docAbstract":"A deep-water ferromanganese crust from a Central Indian Ocean seamount dated previously by 10Be and 230Th(excess) was studied for compositional and textural variations that occurred throughout its growth history. The 10Be/9Be dated interval (upper 32 mm) yields an uniform growth rate of 2.8 ?? 0.1 mm/Ma [Frank, M., O'Nions, R.K., 1998. Sources of Pb for Indian Ocean ferromanganese crusts: a record of Himalayan erosion. Earth Planet. Sci. Lett., 158, pp. 121-130.] which gives an extrapolated age of ~ 26 Ma for the base of the crust at 72 mm and is comparable to the maximum age derived from the Co-model based growth rate estimates. This study shows that Fe-Mn oxyhydroxide precipitation did not occur from the time of emplacement of the seamount during the Eocene (~ 53 Ma) until the late Oligocene (~ 26 Ma). This paucity probably was the result of a nearly overlapping palaeo-CCD and palaeo-depth of crust formation, increased early Eocene productivity, instability and reworking of the surface rocks on the flanks of the seamount, and lack of oxic deep-water in the nascent Indian Ocean. Crust accretion began (older zone) with the formation of isolated cusps of Fe-Mn oxide during a time of high detritus influx, probably due to the early-Miocene intense erosion associated with maximum exhumation of the Himalayas (op. cit.). This cuspate textured zone extends from 72 mm to 42 mm representing the early-Miocene period. Intense polar cooling and increased mixing of deep and intermediate waters at the close of the Oligocene might have led to the increased oxygenation of the bottom-water in the basin. A considerable expansion in the vertical distance between the seafloor depth and the CCD during the early Miocene in addition to the influx of oxygenated bottom-water likely initiated Fe-Mn crust formation. Pillar structure characterises the younger zone, which extends from 40 mm to the surface of the crust, i.e., ~ 15 Ma to Present. This zone is characterised by > 25% higher content of oxide-bound elements than in the older zone, possibly corresponding to further increased oxygenation of bottom-waters, increased stability of the seamount slope, and gradually reduced input of continental detritus from the erosion of the Himalayas. Middle Miocene Antarctic glaciation, which peaked ~ 12-13 Ma ago, increased the oxic bottom-water influx to the basin resulting in accretion of the crust with low detritus. Therefore, the younger crust started to accrete in response to a shift in bottom-water circulation towards the contemporary pattern, which produced a uniform growth rate and pillar structure up to the present. (C) 2000 Published by Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-3227(99)00077-8","issn":"00253227","usgsCitation":"Banakar, V., and Hein, J., 2000, Growth response of a deep-water ferromanganese crust to evolution of the Neogene Indian Ocean: Marine Geology, v. 162, no. 2-4, p. 529-540, https://doi.org/10.1016/S0025-3227(99)00077-8.","startPage":"529","endPage":"540","numberOfPages":"12","costCenters":[],"links":[{"id":206716,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-3227(99)00077-8"},{"id":230616,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"162","issue":"2-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2e08e4b0c8380cd5c247","contributors":{"authors":[{"text":"Banakar, V.K.","contributorId":70135,"corporation":false,"usgs":true,"family":"Banakar","given":"V.K.","affiliations":[],"preferred":false,"id":393895,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hein, J.R. 0000-0002-5321-899X","orcid":"https://orcid.org/0000-0002-5321-899X","contributorId":61429,"corporation":false,"usgs":true,"family":"Hein","given":"J.R.","affiliations":[],"preferred":false,"id":393894,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022501,"text":"70022501 - 2000 - Integrating borehole logs and aquifer tests in aquifer characterization","interactions":[],"lastModifiedDate":"2018-12-10T07:35:53","indexId":"70022501","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"Integrating borehole logs and aquifer tests in aquifer characterization","docAbstract":"Integration of lithologic logs, geophysical logs, and hydraulic tests is critical in characterizing heterogeneous aquifers. Typically only a limited number of aquifer tests can be performed, and these need to be designed to provide hydraulic properties for the principle aquifers in the system. This study describes the integration of logs and aquifer tests in the development of a hydrostratigraphic model for the surficial aquifer system in and around Big Cypress National Preserve in eastern Collier County, Florida. Borehole flowmeter tests provide qualitative permeability profiles in most of 26 boreholes drilled in the Study area. Flow logs indicate the depth of transmissive units, which are correlated across the study area. Comparison to published studies in adjacent areas indicates that the main limestone aquifer of the 000000Tamiami Formation in the study area corresponds with the gray limestone aquifer in western Dade County and the water table and lower Tamiami Aquifer in western Collier County. Four strategically located, multiwell aquifer tests are used to quantify the qualitative permeability profiles provided by the flowmeter log analysis. The hydrostratigraphic model based on these results defines the main aquifer in the central part of the study area as unconfined to semiconfined with a transmissivity as high as 30,000 m2/day. The aquifer decreases in transmissivity to less than 10,000 m2/day in some parts of western Collier County, and becomes confined to the east and northeast of the study area, where transmissivity decreases to below 5000 m2/day.Integration of lithologic logs, geophysical logs, and hydraulic tests is critical in characterizing heterogeneous aquifers. Typically only a limited number of aquifer tests can be performed, and these need to be designed to provide hydraulic properties for the principle aquifers in the system. This study describes the integration of logs and aquifer tests in the development of a hydrostratigraphic model for the surficial aquifer system in and around Big Cypress National Preserve in eastern Collier County, Florida. Borehole flowmeter tests provide qualitative permeability profiles in most of 26 boreholes drilled in the study area. Flow logs indicate the depth of transmissive units, which are correlated across the study area. Comparison to published studies in adjacent areas indicates that the main limestone aquifer of the Tamiami Formation in the study area corresponds with the gray limestone aquifer in western Dade County and the water table and lower Tamiami Aquifer in western Collier County. Four strategically located, multiwell aquifer tests are used to quantify the qualitative permeability profiles provided by the flowmeter log analysis. The hydrostratigraphic model based on these results defines the main aquifer in the central part of the study area as unconfined to semiconfined with a transmissivity as high as 30,000 m2/day. The aquifer decreases in transmissivity to less than 10,000 m2/day in some parts of western Collier County, and becomes confined to the east and northeast of the study area, where transmissivity decreases to below 5000 m2/day.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2000.tb02707.x","issn":"0017467X","usgsCitation":"Paillet, F.L., and Reese, R., 2000, Integrating borehole logs and aquifer tests in aquifer characterization: Ground Water, v. 38, no. 5, p. 713-725, https://doi.org/10.1111/j.1745-6584.2000.tb02707.x.","productDescription":"13 p.","startPage":"713","endPage":"725","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230349,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"38","issue":"5","noUsgsAuthors":false,"publicationDate":"2005-12-13","publicationStatus":"PW","scienceBaseUri":"505a3c76e4b0c8380cd62d65","contributors":{"authors":[{"text":"Paillet, Frederick L.","contributorId":63820,"corporation":false,"usgs":true,"family":"Paillet","given":"Frederick","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":393846,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reese, R.S.","contributorId":17644,"corporation":false,"usgs":true,"family":"Reese","given":"R.S.","email":"","affiliations":[],"preferred":false,"id":393845,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022499,"text":"70022499 - 2000 - Landslide triggering by rain infiltration","interactions":[],"lastModifiedDate":"2018-03-21T14:26:57","indexId":"70022499","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Landslide triggering by rain infiltration","docAbstract":"Landsliding in response to rainfall involves physical processes that operate on disparate timescales. Relationships between these timescales guide development of a mathematical model that uses reduced forms of Richards equation to evaluate effects of rainfall infiltration on landslide occurrence, timing, depth, and acceleration in diverse situations. The longest pertinent timescale is A/D0, where D0 is the maximum hydraulic diffusivity of the soil and A is the catchment area that potentially affects groundwater pressures at a prospective landslide slip surface location with areal coordinates x, y and depth H. Times greater than A/D0 are necessary for establishment of steady background water pressures that develop at (x, y, H) in response to rainfall averaged over periods that commonly range from days to many decades. These steady groundwater pressures influence the propensity for landsliding at (x, y, H), but they do not trigger slope failure. Failure results from rainfall over a typically shorter timescale H2/D0 associated with transient pore pressure transmission during and following storms. Commonly, this timescale ranges from minutes to months. The shortest timescale affecting landslide responses to rainfall is √(H/g), where g is the magnitude of gravitational acceleration. Postfailure landslide motion occurs on this timescale, which indicates that the thinnest landslides accelerate most quickly if all other factors are constant. Effects of hydrologic processes on landslide processes across these diverse timescales are encapsulated by a response function, R(t*) = √(t*/π) exp (-1/t*) - erfc (1/√t*), which depends only on normalized time, t*. Use of R(t*) in conjunction with topographic data, rainfall intensity and duration information, an infinite-slope failure criterion, and Newton's second law predicts the timing, depth, and acceleration of rainfall-triggered landslides. Data from contrasting landslides that exhibit rapid, shallow motion and slow, deep-seated motion corroborate these predictions.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000WR900090","usgsCitation":"Iverson, R.M., 2000, Landslide triggering by rain infiltration: Water Resources Research, v. 36, no. 7, p. 1897-1910, https://doi.org/10.1029/2000WR900090.","productDescription":"14 p.","startPage":"1897","endPage":"1910","costCenters":[],"links":[{"id":479293,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000wr900090","text":"Publisher Index Page"},{"id":230310,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a4445e4b0c8380cd669aa","contributors":{"authors":[{"text":"Iverson, Richard M. 0000-0002-7369-3819 riverson@usgs.gov","orcid":"https://orcid.org/0000-0002-7369-3819","contributorId":536,"corporation":false,"usgs":true,"family":"Iverson","given":"Richard","email":"riverson@usgs.gov","middleInitial":"M.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true},{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"preferred":true,"id":393840,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022491,"text":"70022491 - 2000 - Multispecies reactive tracer test in an aquifer with spatially variable chemical conditions","interactions":[],"lastModifiedDate":"2018-12-10T08:30:10","indexId":"70022491","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Multispecies reactive tracer test in an aquifer with spatially variable chemical conditions","docAbstract":"A field investigation of multispecies reactive transport was conducted in a well‐characterized, sand and gravel aquifer on Cape Cod, Massachusetts. The aquifer is characterized by regions of differing chemical conditions caused by the disposal of secondary sewage effluent. Ten thousand liters of groundwater with added tracers (Br, Cr(VI), and EDTA complexed with Pb, Zn, Cu, and Ni) were injected into the aquifer and distributions of the tracers were monitored for 15 months. Most of the tracers were transported more than 200 m; transport was quantified using spatial moments computed from the results of a series of synoptic samplings. Cr(VI) transport was retarded relative to Br; the retardation factor varied from 1.1 to 2.4 and was dependent on chemical conditions. At 314 days after the injection, dissolved Cr(VI) mass in the tracer cloud had decreased 85%, with the likely cause being reduction to Cr(III) in a suboxic region of the aquifer. Transport of the metal‐EDTA complexes was affected by aqueous complexation, adsorption, and dissolution‐precipitation reactions of Fe oxyhydroxide minerals in the aquifer sediments. Dissolved Pb‐EDTA complexes disappeared from the tracer cloud within 85 days, probably due to metal exchange reactions with Fe and adsorbed Zn (present prior to the injection from contamination by the sewage effluent). About 30% of the Cu‐EDTA complexes remained within the tracer cloud 314 days after injection, even though the thermodynamic stability of the Pb‐EDTA complex is greater than Cu‐EDTA. It is hypothesized that stronger adsorption of Pb2+ to the aquifer sediments causes the Pb‐EDTA complex to disassociate to a greater degree than the Cu‐EDTA complex. The mass of dissolved Zn‐EDTA increased during the first 175 days of the tracer test to 140% of the mass injected, with the increase due to desorption of sewage‐derived Zn. Dissolved Ni‐EDTA mass remained nearly constant throughout the tracer test, apparently only participating in reversible adsorption reactions. The results of the field experiment provide a chemically complex data set that can be used in the testing of reactive transport models of flow coupled with chemical reactions.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1999WR900282","usgsCitation":"Davis, J., Kent, D., Coston, J., Hess, K., and Joye, J., 2000, Multispecies reactive tracer test in an aquifer with spatially variable chemical conditions: Water Resources Research, v. 36, no. 1, p. 119-134, https://doi.org/10.1029/1999WR900282.","productDescription":"16 p.","startPage":"119","endPage":"134","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230800,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a60a0e4b0c8380cd715b2","contributors":{"authors":[{"text":"Davis, J.A.","contributorId":71694,"corporation":false,"usgs":true,"family":"Davis","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":393811,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kent, D.B.","contributorId":16588,"corporation":false,"usgs":true,"family":"Kent","given":"D.B.","email":"","affiliations":[],"preferred":false,"id":393807,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Coston, J.A.","contributorId":59572,"corporation":false,"usgs":true,"family":"Coston","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":393810,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hess, K.M.","contributorId":39415,"corporation":false,"usgs":true,"family":"Hess","given":"K.M.","email":"","affiliations":[],"preferred":false,"id":393808,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Joye, J.L.","contributorId":56389,"corporation":false,"usgs":true,"family":"Joye","given":"J.L.","email":"","affiliations":[],"preferred":false,"id":393809,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70022488,"text":"70022488 - 2000 - Using structural equation modeling to investigate relationships among ecological variables","interactions":[],"lastModifiedDate":"2012-03-12T17:19:43","indexId":"70022488","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1573,"text":"Environmental and Ecological Statistics","active":true,"publicationSubtype":{"id":10}},"title":"Using structural equation modeling to investigate relationships among ecological variables","docAbstract":"Structural equation modeling is an advanced multivariate statistical process with which a researcher can construct theoretical concepts, test their measurement reliability, hypothesize and test a theory about their relationships, take into account measurement errors, and consider both direct and indirect effects of variables on one another. Latent variables are theoretical concepts that unite phenomena under a single term, e.g., ecosystem health, environmental condition, and pollution (Bollen, 1989). Latent variables are not measured directly but can be expressed in terms of one or more directly measurable variables called indicators. For some researchers, defining, constructing, and examining the validity of latent variables may be the end task of itself. For others, testing hypothesized relationships of latent variables may be of interest. We analyzed the correlation matrix of eleven environmental variables from the U.S. Environmental Protection Agency's (USEPA) Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) using methods of structural equation modeling. We hypothesized and tested a conceptual model to characterize the interdependencies between four latent variables-sediment contamination, natural variability, biodiversity, and growth potential. In particular, we were interested in measuring the direct, indirect, and total effects of sediment contamination and natural variability on biodiversity and growth potential. The model fit the data well and accounted for 81% of the variability in biodiversity and 69% of the variability in growth potential. It revealed a positive total effect of natural variability on growth potential that otherwise would have been judged negative had we not considered indirect effects. That is, natural variability had a negative direct effect on growth potential of magnitude -0.3251 and a positive indirect effect mediated through biodiversity of magnitude 0.4509, yielding a net positive total effect of 0.1258. Natural variability had a positive direct effect on biodiversity of magnitude 0.5347 and a negative indirect effect mediated through growth potential of magnitude -0.1105 yielding a positive total effects of magnitude 0.4242. Sediment contamination had a negative direct effect on biodiversity of magnitude -0.1956 and a negative indirect effect on growth potential via biodiversity of magnitude -0.067. Biodiversity had a positive effect on growth potential of magnitude 0.8432, and growth potential had a positive effect on biodiversity of magnitude 0.3398. The correlation between biodiversity and growth potential was estimated at 0.7658 and that between sediment contamination and natural variability at -0.3769.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental and Ecological Statistics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/A:1009662930292","issn":"13528505","usgsCitation":"Malaeb, Z., Summers, J., and Pugesek, B., 2000, Using structural equation modeling to investigate relationships among ecological variables: Environmental and Ecological Statistics, v. 7, no. 1, p. 93-111, https://doi.org/10.1023/A:1009662930292.","startPage":"93","endPage":"111","numberOfPages":"19","costCenters":[],"links":[{"id":230724,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206757,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1009662930292"}],"volume":"7","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc0abe4b08c986b32a25f","contributors":{"authors":[{"text":"Malaeb, Z.A.","contributorId":77694,"corporation":false,"usgs":true,"family":"Malaeb","given":"Z.A.","affiliations":[],"preferred":false,"id":393798,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Summers, J.Kevin","contributorId":25721,"corporation":false,"usgs":true,"family":"Summers","given":"J.Kevin","email":"","affiliations":[],"preferred":false,"id":393796,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Pugesek, B.H.","contributorId":45666,"corporation":false,"usgs":true,"family":"Pugesek","given":"B.H.","affiliations":[],"preferred":false,"id":393797,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022486,"text":"70022486 - 2000 - Contaminant distribution and accumulation in the surface sediments of Long Island Sound","interactions":[],"lastModifiedDate":"2017-11-18T12:19:38","indexId":"70022486","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2220,"text":"Journal of Coastal Research","active":true,"publicationSubtype":{"id":10}},"title":"Contaminant distribution and accumulation in the surface sediments of Long Island Sound","docAbstract":"The distribution of contaminants in surface sediments has been measured and mapped as part of a U.S. Geological Survey study of the sediment quality and dynamics of Long Island Sound. Surface samples from 219 stations were analyzed for trace (Ag, Ba, Cd, Cr, Cu, Hg, Ni, Pb, V, Zn and Zr) and major (Al, Fe, Mn, Ca, and Ti) elements, grain size, and Clostridium perfringens spores. Principal Components Analysis was used to identify metals that may covary as a function of common sources or geochemistry. The metallic elements generally have higher concentrations in fine-grained deposits, and their transport and depositional patterns mimic those of small particles. Fine-grained particles are remobilized and transported from areas of high bottom energy and deposited in less dynamic regions of the Sound. Metal concentrations in bottom sediments are high in the western part of the Sound and low in the bottom-scoured regions of the eastern Sound. The sediment chemistry was compared to model results (Signell et al., 1998) and maps of sedimentary environments (Knebel et al., 1999) to better understand the processes responsible for contaminant distribution across the Sound. Metal concentrations were normalized to grain-size and the resulting ratios are uniform in the depositional basins of the Sound and show residual signals in the eastern end as well as in some local areas. The preferential transport of fine-grained material from regions of high bottom stress is probably the dominant factor controlling the metal concentrations in different regions of Long Island Sound. This physical redistribution has implications for environmental management in the region.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Coastal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"07490208","usgsCitation":"Mecray, E., and Buchholtz ten Brink, M.R., 2000, Contaminant distribution and accumulation in the surface sediments of Long Island Sound: Journal of Coastal Research, v. 16, no. 3, p. 575-590.","productDescription":"16 p.","startPage":"575","endPage":"590","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":230683,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Long Island Sound","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n 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]\n}","volume":"16","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fa30e4b0c8380cd4d994","contributors":{"authors":[{"text":"Mecray, E.L.","contributorId":14840,"corporation":false,"usgs":true,"family":"Mecray","given":"E.L.","email":"","affiliations":[],"preferred":false,"id":393793,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buchholtz ten Brink, Marilyn R.","contributorId":88021,"corporation":false,"usgs":true,"family":"Buchholtz ten Brink","given":"Marilyn","email":"","middleInitial":"R.","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":393794,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022472,"text":"70022472 - 2000 - Ore-fluid evolution at the Getchell Carlin-type gold deposit, Nevada, USA","interactions":[],"lastModifiedDate":"2022-12-22T16:56:52.711292","indexId":"70022472","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1593,"text":"European Journal of Mineralogy","active":true,"publicationSubtype":{"id":10}},"title":"Ore-fluid evolution at the Getchell Carlin-type gold deposit, Nevada, USA","docAbstract":"Minerals and fluid-inclusion populations were examined using petrography, microthermometry, quadrupole mass-spectrometer gas analyses and stable-isotope studies to characterize fluids responsible for gold mineralization at the Getchell Carlin-type gold deposit. The gold-ore assemblage at Getchell is superimposed on quartz-pyrite vein mineralization associated with a Late-Cretaceous granodiorite stock that intruded Lower-Paleozoic sedimentary rocks. The ore assemblage, of mid-Tertiary age, consists of disseminated arsenian pyrite that contains submicrometer gold, jasperoid quartz, and later fluorite and orpiment that fill fractures and vugs. Late ore-stage realgar and calcite enclose ore-stage minerals.
Pre-ore quartz trapped fluids with a wide range of salinities (1 to 21 wt.% NaCl equivalent), gas compositions (H2O, CO2, and CH4), and temperatures (120 to > 360°C). Oxygen- and hydrogen-isotope ratios indicate that pre-ore fluids likely had a magmatic source, and were associated with intrusion of the granodiorite stock and related dikes.
Ore-stage jasperoid contains moderate salinity, aqueous fluid inclusions trapped at 180 to 220°C. Ore fluids contain minor CO2 and trace H2S that allowed the fluid to react with limestone host rocks and transport gold, respectively. Aqueous inclusions in fluorite indicate that fluid temperatures declined to ∼ 175°C by the end of ore-stage mineralization. As the hydrothermal system collapsed, fluid temperatures declined to 155 to 115°C and realgar and calcite precipitated.
Inclusion fluids in ore-stage minerals have high δDH2O and δ18OH2O values that indicate that the fluid had a deep source, and had a metamorphic or magmatic origin, or both. Late ore-stage fluids extend to lower δH2O values, and have a wider range of δ18OH2O values suggesting dilution by variably exchanged meteoric waters.
Results show that deeply sourced ore fluids rose along the Getchell fault system, where they dissolved carbonate wall rocks and deposited gold-enriched pyrite and jasperoid quartz. Gold and pyrite precipitated together as H2S in the ore fluids reacted with iron in the host rocks. As ore fluids mixed with local aquifer fluids, ore fluids became cooler and more dilute. Cooling caused precipitation of ore-stage fluorite and orpiment, and late ore-stage realgar. Phase separation and/or neutralization of the ore fluid during the waning stages of the hydrothermal ore system led to deposition of late ore-stage calcite.
","language":"English","publisher":"E. Schweizerbart'sche Verldghuchhandlung","doi":"10.1127/0935-1221/2000/0012-0195","usgsCitation":"Cline, J.S., and Hofstra, A.H., 2000, Ore-fluid evolution at the Getchell Carlin-type gold deposit, Nevada, USA: European Journal of Mineralogy, v. 12, no. 1, p. 195-212, https://doi.org/10.1127/0935-1221/2000/0012-0195.","productDescription":"18 p.","startPage":"195","endPage":"212","costCenters":[{"id":171,"text":"Central Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"links":[{"id":230500,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":410942,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.geoscienceworld.org/eurjmin/article/12/1/195/61682/Ore-fluid-evolution-at-the-Getchell-Carlin-type"}],"country":"United States","state":"Nevada","city":"Getchell","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -117.70339965820312,\n 40.681679458715635\n ],\n [\n -116.75582885742188,\n 40.681679458715635\n ],\n [\n -116.75582885742188,\n 41.33970040774419\n ],\n [\n -117.70339965820312,\n 41.33970040774419\n ],\n [\n -117.70339965820312,\n 40.681679458715635\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"12","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6f71e4b0c8380cd75acc","contributors":{"authors":[{"text":"Cline, Jean S.","contributorId":83628,"corporation":false,"usgs":true,"family":"Cline","given":"Jean","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":393749,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hofstra, Albert H. 0000-0002-2450-1593 ahofstra@usgs.gov","orcid":"https://orcid.org/0000-0002-2450-1593","contributorId":1302,"corporation":false,"usgs":true,"family":"Hofstra","given":"Albert","email":"ahofstra@usgs.gov","middleInitial":"H.","affiliations":[{"id":171,"text":"Central Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":393750,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022466,"text":"70022466 - 2000 - Development and application of a comprehensive simulation model to evaluate impacts of watershed structures and irrigation water use on streamflow and groundwater: The case of Wet Walnut Creek Watershed, Kansas, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:19:44","indexId":"70022466","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Development and application of a comprehensive simulation model to evaluate impacts of watershed structures and irrigation water use on streamflow and groundwater: The case of Wet Walnut Creek Watershed, Kansas, USA","docAbstract":"This paper presents the results of a comprehensive modeling study of surface and groundwater systems, including stream-aquifer interactions, for the Wet Walnut Creek Watershed in west-central Kansas. The main objective of this study was to assess the impacts of watershed structures and irrigation water use on streamflow and groundwater levels, which in turn affect availability of water for the Cheyenne Bottoms Wildlife Refuge Management area. The surface-water flow model, POTYLDR, and the groundwater flow model, MODFLOW, were combined into an integrated, watershed-scale, continuous simulation model. Major revisions and enhancements were made to the POTYLDR and MODFLOW models for simulating the detailed hydrologic budget for the Wet Walnut Creek Watershed. The computer simulation model was calibrated and verified using historical streamflow records (at Albert and Nekoma gaging stations), reported irrigation water use, observed water-level elevations in watershed structure pools, and groundwater levels in the alluvial aquifer system. To assess the impact of watershed structures and irrigation water use on streamflow and groundwater levels, a number of hypothetical management scenarios were simulated under various operational criteria for watershed structures and different annual limits on water use for irrigation. A standard 'base case' was defined to allow comparative analysis of the results of different scenarios. The simulated streamflows showed that watershed structures decrease both streamflows and groundwater levels in the watershed. The amount of water used for irrigation has a substantial effect on the total simulated streamflow and groundwater levels, indicating that irrigation is a major budget item for managing water resources in the watershed. (C) 2000 Elsevier Science B.V.This paper presents the results of a comprehensive modeling study of surface and groundwater systems, including stream-aquifer interactions, for the Wet Walnut Creek Watershed in west-central Kansas. The main objective of this study was to assess the impacts of watershed structures and irrigation water use on streamflow and groundwater levels, which in turn affect availability of water for the Cheyenne Bottoms Wildlife Refuge Management area. The surface-water flow model, POTYLDR, and the groundwater flow model, MODFLOW, were combined into an integrated, watershed-scale, continuous simulation model. Major revisions and enhancements were made to the POTYLDR and MODFLOW models for simulating the detailed hydrologic budget for the Wet Walnut Creek Watershed. The computer simulation model was calibrated and verified using historical streamflow records (at Albert and Nekoma gaging stations), reported irrigation water use, observed water-level elevations in watershed structure pools, and groundwater levels in the alluvial aquifer system. To assess the impact of watershed structures and irrigation water use on streamflow and groundwater levels, a number of hypothetical management scenarios were simulated under various operational criteria for watershed structures and different annual limits on water use for irrigation. A standard `base case' was defined to allow comparative analysis of the results of different scenarios. The simulated streamflows showed that watershed structures decrease both streamflows and groundwater levels in the watershed. The amount of water used for irrigation has a substantial effect on the total simulated streamflow and groundwater levels, indicating that irrigation is a major budget item for managing water resources in the watershed.A comprehensive simulation model that combines the surface water flow model POTYLDR and the groundwater flow model MODFLOW was used to study the impacts of watershed structures (e.g., dams) and irrigation water use (including stream-aquifer interactions) on streamflow and groundwater. The model was revised, enhanced, calibrated, and verified, then applied to evaluate the hydrologic budget for Wet Wal","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Science B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0022-1694(00)00295-X","issn":"00221694","usgsCitation":"Ramireddygari, S., Sophocleous, M., Koelliker, J., Perkins, S., and Govindaraju, R., 2000, Development and application of a comprehensive simulation model to evaluate impacts of watershed structures and irrigation water use on streamflow and groundwater: The case of Wet Walnut Creek Watershed, Kansas, USA: Journal of Hydrology, v. 236, no. 3-4, p. 223-246, https://doi.org/10.1016/S0022-1694(00)00295-X.","startPage":"223","endPage":"246","numberOfPages":"24","costCenters":[],"links":[{"id":206636,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(00)00295-X"},{"id":230427,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"236","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0016e4b0c8380cd4f5a5","contributors":{"authors":[{"text":"Ramireddygari, S.R.","contributorId":63191,"corporation":false,"usgs":true,"family":"Ramireddygari","given":"S.R.","email":"","affiliations":[],"preferred":false,"id":393733,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sophocleous, M.A.","contributorId":18032,"corporation":false,"usgs":true,"family":"Sophocleous","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":393731,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Koelliker, J.K.","contributorId":49940,"corporation":false,"usgs":true,"family":"Koelliker","given":"J.K.","email":"","affiliations":[],"preferred":false,"id":393732,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Perkins, S.P.","contributorId":12211,"corporation":false,"usgs":true,"family":"Perkins","given":"S.P.","email":"","affiliations":[],"preferred":false,"id":393729,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Govindaraju, R.S.","contributorId":15365,"corporation":false,"usgs":true,"family":"Govindaraju","given":"R.S.","email":"","affiliations":[],"preferred":false,"id":393730,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70022464,"text":"70022464 - 2000 - Intra-basinal water movements induced by faulting: The August 17, 1999, Golcuk (Izmit Bay) earthquake (M(W) = 7.4)","interactions":[],"lastModifiedDate":"2012-03-12T17:19:50","indexId":"70022464","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Intra-basinal water movements induced by faulting: The August 17, 1999, Golcuk (Izmit Bay) earthquake (M(W) = 7.4)","docAbstract":"A strong earthquake (M(w) = 7.4) occurred near the town of Golcuk, Izmit Bay, Western Turkey, at 00:01 GMT on August 17, 1999. Izmit Bay is a E-W trending pull-apart basin with a surface area of about 300 km2 along the North Anatolian Fault Zone (NAF), in the eastern extension of the Sea of Marmara. The earthquake was caused by a westerly movement of the Anatolian plate along NAF and was accompanied by isolated, chaotic water movements along the northern and southern shores of the bay. At localities along the shoreline a sudden drop in sea level, and a subsequent rise was prominent. The mode of observed sea-level movements rules out the occurrence of a basin-wide tsunami, sensu stricto. Instead, the water movements are attributed to localized sudden dip-slip movements of fault blocks in this pull-apart basin. (C) 2000 Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-3227(00)00090-6","issn":"00253227","usgsCitation":"Ozturk, H., Koral, H., and Geist, E., 2000, Intra-basinal water movements induced by faulting: The August 17, 1999, Golcuk (Izmit Bay) earthquake (M(W) = 7.4): Marine Geology, v. 170, no. 3-4, p. 263-270, https://doi.org/10.1016/S0025-3227(00)00090-6.","startPage":"263","endPage":"270","numberOfPages":"8","costCenters":[],"links":[{"id":206616,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-3227(00)00090-6"},{"id":230387,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"170","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3dbbe4b0c8380cd637c6","contributors":{"authors":[{"text":"Ozturk, H.","contributorId":53966,"corporation":false,"usgs":true,"family":"Ozturk","given":"H.","email":"","affiliations":[],"preferred":false,"id":393723,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Koral, H.","contributorId":70955,"corporation":false,"usgs":true,"family":"Koral","given":"H.","email":"","affiliations":[],"preferred":false,"id":393724,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Geist, E.L. 0000-0003-0611-1150","orcid":"https://orcid.org/0000-0003-0611-1150","contributorId":71993,"corporation":false,"usgs":true,"family":"Geist","given":"E.L.","affiliations":[],"preferred":false,"id":393725,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022461,"text":"70022461 - 2000 - Climatic and biotic controls on annual carbon storage in Amazonian ecosystems","interactions":[],"lastModifiedDate":"2012-03-12T17:19:50","indexId":"70022461","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1839,"text":"Global Ecology and Biogeography","active":true,"publicationSubtype":{"id":10}},"title":"Climatic and biotic controls on annual carbon storage in Amazonian ecosystems","docAbstract":"1 The role of undisturbed tropical land ecosystems in the global carbon budget is not well understood. It has been suggested that inter-annual climate variability can affect the capacity of these ecosystems to store carbon in the short term. In this paper, we use a transient version of the Terrestrial Ecosystem Model (TEM) to estimate annual carbon storage in undisturbed Amazonian ecosystems during the period 1980-94, and to understand the underlying causes of the year-to-year variations in net carbon storage for this region. 2 We estimate that the total carbon storage in the undisturbed ecosystems of the Amazon Basin in 1980 was 127.6 Pg C, with about 94.3 Pg C in vegetation and 33.3 Pg C in the reactive pool of soil organic carbon. About 83% of the total carbon storage occurred in tropical evergreen forests. Based on our model's results, we estimate that, over the past 15 years, the total carbon storage has increased by 3.1 Pg C (+ 2%), with a 1.9-Pg C (+2%) increase in vegetation carbon and a 1.2-Pg C (+4%) increase in reactive soil organic carbon. The modelled results indicate that the largest relative changes in net carbon storage have occurred in tropical deciduous forests, but that the largest absolute changes in net carbon storage have occurred in the moist and wet forests of the Basin. 3 Our results show that the strength of interannual variations in net carbon storage of undisturbed ecosystems in the Amazon Basin varies from a carbon source of 0.2 Pg C/year to a carbon sink of 0.7 Pg C/year. Precipitation, especially the amount received during the drier months, appears to be a major controller of annual net carbon storage in the Amazon Basin. Our analysis indicates further that changes in precipitation combine with changes in temperature to affect net carbon storage through influencing soil moisture and nutrient availability. 4 On average, our results suggest that the undisturbed Amazonian ecosystems accumulated 0.2 Pg C/year as a result of climate variability and increasing atmospheric CO2 over the study period. This amount is large enough to have compensated for most of the carbon losses associated with tropical deforestation in the Amazon during the same period. 5 Comparisons with empirical data indicate that climate variability and CO2 fertilization explain most of the variation in net carbon storage for the undisturbed ecosystems. Our analyses suggest that assessment of the regional carbon budget in the tropics should be made over at least one cycle of El Nino-Southern Oscillation because of inter-annual climate variability. Our analyses also suggest that proper scaling of the site-specific and sub-annual measurements of carbon fluxes to produce Basin-wide flux estimates must take into account seasonal and spatial variations in net carbon storage.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Global Ecology and Biogeography","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1046/j.1365-2699.2000.00198.x","issn":"1466822X","usgsCitation":"Tian, H., Melillo, J.M., Kicklighter, D., McGuire, A., Helfrich, J., Moore, B., and Vorosmarty, C., 2000, Climatic and biotic controls on annual carbon storage in Amazonian ecosystems: Global Ecology and Biogeography, v. 9, no. 4, p. 315-335, https://doi.org/10.1046/j.1365-2699.2000.00198.x.","startPage":"315","endPage":"335","numberOfPages":"21","costCenters":[],"links":[{"id":479334,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1046/j.1365-2699.2000.00198.x","text":"Publisher Index Page"},{"id":230348,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206599,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1046/j.1365-2699.2000.00198.x"}],"volume":"9","issue":"4","noUsgsAuthors":false,"publicationDate":"2001-12-25","publicationStatus":"PW","scienceBaseUri":"5059f65be4b0c8380cd4c6fc","contributors":{"authors":[{"text":"Tian, H.","contributorId":43524,"corporation":false,"usgs":true,"family":"Tian","given":"H.","affiliations":[],"preferred":false,"id":393709,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Melillo, J. M.","contributorId":73139,"corporation":false,"usgs":false,"family":"Melillo","given":"J.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":393710,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kicklighter, D. W.","contributorId":31537,"corporation":false,"usgs":false,"family":"Kicklighter","given":"D. W.","affiliations":[{"id":13627,"text":"Woods Hole Oceanographic Institution, Woods Hole, MA","active":true,"usgs":false}],"preferred":false,"id":393708,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McGuire, A. D.","contributorId":16552,"corporation":false,"usgs":true,"family":"McGuire","given":"A. D.","affiliations":[],"preferred":false,"id":393707,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Helfrich, J. Iii","contributorId":74535,"corporation":false,"usgs":true,"family":"Helfrich","given":"J.","suffix":"Iii","affiliations":[],"preferred":false,"id":393711,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Moore, B. III","contributorId":96845,"corporation":false,"usgs":true,"family":"Moore","given":"B.","suffix":"III","email":"","affiliations":[],"preferred":false,"id":393712,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Vorosmarty, C. J.","contributorId":104232,"corporation":false,"usgs":false,"family":"Vorosmarty","given":"C. J.","affiliations":[],"preferred":false,"id":393713,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70022451,"text":"70022451 - 2000 - Spatial and temporal sensitivity of hydrogeomorphic response and recovery to deforestation, agriculture, and floods","interactions":[],"lastModifiedDate":"2022-08-17T13:37:37.589417","indexId":"70022451","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3059,"text":"Physical Geography","active":true,"publicationSubtype":{"id":10}},"title":"Spatial and temporal sensitivity of hydrogeomorphic response and recovery to deforestation, agriculture, and floods","docAbstract":"Clear-cut logging followed by agricultural activity caused hydrologic and geomorphic changes in North Fish Creek, a Wisconsin tributary to Lake Superior. Hydro-geomorphic responses to changes in land use were sensitive to the location of reaches along the main stem and to the relative timing of large floods. Hydrologic and sediment-load modeling indicates that flood peaks were three times larger and sediment loads were five times larger during maximum agricultural activity in the 1920s and 1930s than prior to about 1890, when forest cover was dominant. Following logging, overbank sedimentation rates in the lower main stem increased four to six times above pre-settlement rates. Accelerated streambank and channel erosion in the upper main stem have been and continue to be primary sources of sediment to downstream reaches. Extreme floods in 1941 and 1946, followed by frequent moderate floods through 1954, caused extensive geomorphic changes along the entire main stem. Sedimentation rates in the lower main stem may have decreased in the last several decades as agricultural activity declined. However, geomorphic recovery is slow, as incised channels in the upper main stem function as efficient conveyors of watershed surface runoff and thereby continue to promote flooding and sedimentation problems downstream.
","language":"English","publisher":"Taylor & Francis","doi":"10.1080/02723646.2000.10642701","issn":"02723646","usgsCitation":"Fitzpatrick, F., and Knox, J., 2000, Spatial and temporal sensitivity of hydrogeomorphic response and recovery to deforestation, agriculture, and floods: Physical Geography, v. 21, no. 2, p. 89-108, https://doi.org/10.1080/02723646.2000.10642701.","productDescription":"20 p.","startPage":"89","endPage":"108","costCenters":[],"links":[{"id":230758,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Wisconsin","otherGeospatial":"Lake Superior, North Fish Creek","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -91.1151123046875,\n 46.56122097002429\n ],\n [\n -91.15116119384764,\n 46.55319428348575\n ],\n [\n -91.14704132080078,\n 46.52060318945508\n ],\n [\n -90.90911865234374,\n 46.586709628118015\n ],\n [\n -90.94242095947266,\n 46.605582392244486\n ],\n [\n -91.1151123046875,\n 46.56122097002429\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"21","issue":"2","noUsgsAuthors":false,"publicationDate":"2013-05-15","publicationStatus":"PW","scienceBaseUri":"505b9444e4b08c986b31a989","contributors":{"authors":[{"text":"Fitzpatrick, F. A. 0000-0002-9748-7075","orcid":"https://orcid.org/0000-0002-9748-7075","contributorId":61446,"corporation":false,"usgs":true,"family":"Fitzpatrick","given":"F. A.","affiliations":[],"preferred":false,"id":393660,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Knox, J.C.","contributorId":39970,"corporation":false,"usgs":true,"family":"Knox","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":393659,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022450,"text":"70022450 - 2000 - A seismic landslide susceptibility rating of geologic units based on analysis of characterstics of landslides triggered by the 17 January, 1994 Northridge, California earthquake","interactions":[],"lastModifiedDate":"2019-06-05T11:45:01","indexId":"70022450","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1517,"text":"Engineering Geology","active":true,"publicationSubtype":{"id":10}},"title":"A seismic landslide susceptibility rating of geologic units based on analysis of characterstics of landslides triggered by the 17 January, 1994 Northridge, California earthquake","docAbstract":"One of the most significant effects of the 17 January, 1994 Northridge, California earthquake (M=6.7) was the triggering of thousands of landslides over a broad area. Some of these landslides damaged and destroyed homes and other structures, blocked roads, disrupted pipelines, and caused other serious damage. Analysis of the distribution and characteristics of these landslides is important in understanding what areas may be susceptible to landsliding in future earthquakes. We analyzed the frequency, distribution, and geometries of triggered landslides in the Santa Susana 7.5′ quadrangle, an area of intense seismic landslide activity near the earthquake epicenter. Landslides occurred primarily in young (Late Miocene through Pleistocene) uncemented or very weakly cemented sediment that has been repeatedly folded, faulted, and uplifted in the past 1.5 million years. The most common types of landslide triggered by the earthquake were highly disrupted, shallow falls and slides of rock and debris. Far less numerous were deeper, more coherent slumps and block slides, primarily occurring in more cohesive or competent materials. The landslides in the Santa Susana quadrangle were divided into two samples: single landslides (1502) and landslide complexes (60), which involved multiple coalescing failures of surficial material. We described landslide morphologies by computing simple morphometric parameters (area, length, width, aspect ratio, slope angle). To quantify and rank the relative susceptibility of each geologic unit to seismic landsliding, we calculated two indices: (1) the susceptibility index, which is the ratio (given as a percentage) of the area covered by landslide sources within a geologic unit to the total outcrop area of that unit; and (2) the frequency index [given in landslides per square kilometer (ls/km2)], which is the total number of landslides within each geologic unit divided by the outcrop area of that unit. Susceptibility categories include very high (>2.5% landslide area or >30 ls/km2), high (1.0–2.5% landslide area or 10–30 ls/km2), moderate (0.5–1.0% landslide area or 3–10 ls/km2), and low (<0.5% landslide area and <3 ls/km2).