{"pageNumber":"330","pageRowStart":"8225","pageSize":"25","recordCount":16506,"records":[{"id":70185179,"text":"70185179 - 2002 - Field and laboratory investigations of inactivation of viruses (PRD1 and MS2) attached to iron oxide-coated quartz sand","interactions":[],"lastModifiedDate":"2018-11-26T09:46:11","indexId":"70185179","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Field and laboratory investigations of inactivation of viruses (PRD1 and MS2) attached to iron oxide-coated quartz sand","docAbstract":"<p><span>Field and laboratory experiments were conducted to investigate inactivation of viruses attached to mineral surfaces. In a natural gradient transport field experiment, bacteriophage PRD1, radiolabeled with </span><sup>32</sup><span>P, was injected into a ferric oxyhydroxide-coated sand aquifer with bromide and linear alkylbenzene sulfonates. In a zone of the aquifer contaminated by secondary sewage infiltration, small fractions of infective and </span><sup>32</sup><span>P-labeled PRD1 broke through with the bromide tracer, followed by the slow release of 84% of the </span><sup>32</sup><span>P activity and only 0.011% of the infective PRD1. In the laboratory experiments, the inactivation of PRD1, labeled with </span><sup>35</sup><span>S (protein capsid), and MS2, dual radiolabeled with </span><sup>35</sup><span>S (protein capsid) and </span><sup>32</sup><span>P (nucleic acid), was monitored in the presence of groundwater and sediment from the contaminated zone of the field site. Release of infective viruses decreased at a much faster rate than release of the radiolabels, indicating that attached viruses were undergoing surface inactivation. Disparities between </span><sup>32</sup><span>P and</span><sup>35</sup><span>S release suggest that the inactivated viruses were released in a disintegrated state. Comparison of estimated solution and surface inactivation rates indicates solution inactivation is ∼3 times as fast as surface inactivation. The actual rate of surface inactivation may be substantially underestimated owing to slow release of inactivated viruses.</span></p>","language":"English","publisher":"American Chemical Society","doi":"10.1021/es011285y","usgsCitation":"Ryan, J.N., Harvey, R.W., Metge, D.W., Elimelech, M., Navigato, T., and Pieper, A.P., 2002, Field and laboratory investigations of inactivation of viruses (PRD1 and MS2) attached to iron oxide-coated quartz sand: Environmental Science & Technology, v. 36, no. 11, p. 2403-2413, https://doi.org/10.1021/es011285y.","productDescription":"11 p. ","startPage":"2403","endPage":"2413","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":337684,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"11","noUsgsAuthors":false,"publicationDate":"2002-04-19","publicationStatus":"PW","scienceBaseUri":"58ca52d5e4b0849ce97c8702","contributors":{"authors":[{"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":684622,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Harvey, Ronald W. 0000-0002-2791-8503 rwharvey@usgs.gov","orcid":"https://orcid.org/0000-0002-2791-8503","contributorId":564,"corporation":false,"usgs":true,"family":"Harvey","given":"Ronald","email":"rwharvey@usgs.gov","middleInitial":"W.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":684623,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Metge, David W. dwmetge@usgs.gov","contributorId":663,"corporation":false,"usgs":true,"family":"Metge","given":"David","email":"dwmetge@usgs.gov","middleInitial":"W.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":684624,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Elimelech, Menachem","contributorId":189312,"corporation":false,"usgs":false,"family":"Elimelech","given":"Menachem","email":"","affiliations":[],"preferred":false,"id":684625,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Navigato, Theresa","contributorId":189370,"corporation":false,"usgs":false,"family":"Navigato","given":"Theresa","email":"","affiliations":[],"preferred":false,"id":684626,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Pieper, Ann P.","contributorId":189371,"corporation":false,"usgs":false,"family":"Pieper","given":"Ann","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":684627,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70185181,"text":"70185181 - 2002 - Editors' message: The past year and thanks","interactions":[],"lastModifiedDate":"2018-11-28T09:32:59","indexId":"70185181","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"Editors' message: The past year and thanks","docAbstract":"<p>No abstract available.</p>","language":"English","publisher":"Springer","doi":"10.1007/s10040-002-0191-y","usgsCitation":"Schneider, R., and Voss, C.I., 2002, Editors' message: The past year and thanks: Hydrogeology Journal, v. 10, no. 1, p. 1-2, https://doi.org/10.1007/s10040-002-0191-y.","productDescription":"2 p. ","startPage":"1","endPage":"2","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":478795,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1007/s10040-002-0191-y","text":"Publisher Index Page"},{"id":337686,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"1","noUsgsAuthors":false,"publicationDate":"2002-01-12","publicationStatus":"PW","scienceBaseUri":"58ca52d5e4b0849ce97c8700","contributors":{"authors":[{"text":"Schneider, Robert","contributorId":102460,"corporation":false,"usgs":true,"family":"Schneider","given":"Robert","email":"","affiliations":[],"preferred":false,"id":684633,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Voss, Clifford I. 0000-0001-5923-2752 cvoss@usgs.gov","orcid":"https://orcid.org/0000-0001-5923-2752","contributorId":1559,"corporation":false,"usgs":true,"family":"Voss","given":"Clifford","email":"cvoss@usgs.gov","middleInitial":"I.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":684634,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70185182,"text":"70185182 - 2002 - Atmospheric mercury deposition during the last 270 years: A glacial ice core record of natural and anthropogenic sources","interactions":[],"lastModifiedDate":"2018-11-28T08:24:55","indexId":"70185182","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Atmospheric mercury deposition during the last 270 years: A glacial ice core record of natural and anthropogenic sources","docAbstract":"<p><span>Mercury (Hg) contamination of aquatic ecosystems and subsequent methylmercury bioaccumulation are significant environmental problems of global extent. At regional to global scales, the primary mechanism of Hg contamination is atmospheric Hg transport. Thus, a better understanding of the long-term history of atmospheric Hg cycling and quantification of the sources is critical for assessing the regional and global impact of anthropogenic Hg emissions. Ice cores collected from the Upper Fremont Glacier (UFG), Wyoming, contain a high-resolution record of total atmospheric Hg deposition (ca. 1720−1993). Total Hg in 97 ice-core samples was determined with trace-metal clean handling methods and low-level analytical procedures to reconstruct the first and most comprehensive atmospheric Hg deposition record of its kind yet available from North America. The record indicates major atmospheric releases of both natural and anthropogenic Hg from regional and global sources. Integrated over the past 270-year ice-core history, anthropogenic inputs contributed 52%, volcanic events 6%, and background sources 42%. More significantly, during the last 100 years, anthropogenic sources contributed 70% of the total Hg input. Unlike the 2−7-fold increase observed from preindustrial times (before 1840) to the mid-1980s in sediment-core records, the UFG record indicates a 20-fold increase for the same period. The sediment-core records, however, are in agreement with the last 10 years of this ice-core record, indicating declines in atmospheric Hg deposition.</span></p>","language":"English","publisher":"American Chemical Society","doi":"10.1021/es0157503","usgsCitation":"Schuster, P.F., Krabbenhoft, D.P., Naftz, D.L., Cecil, L.D., Olson, M.L., DeWild, J.F., Susong, D.D., Green, J.R., and Abbott, M.L., 2002, Atmospheric mercury deposition during the last 270 years: A glacial ice core record of natural and anthropogenic sources: Environmental Science & Technology, v. 36, no. 11, p. 2303-2310, https://doi.org/10.1021/es0157503.","productDescription":"8 p. ","startPage":"2303","endPage":"2310","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":337687,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"11","noUsgsAuthors":false,"publicationDate":"2002-04-24","publicationStatus":"PW","scienceBaseUri":"58ca52d4e4b0849ce97c86fe","contributors":{"authors":[{"text":"Schuster, Paul F. 0000-0002-8314-1372 pschuste@usgs.gov","orcid":"https://orcid.org/0000-0002-8314-1372","contributorId":1360,"corporation":false,"usgs":true,"family":"Schuster","given":"Paul","email":"pschuste@usgs.gov","middleInitial":"F.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":684635,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Krabbenhoft, David P. 0000-0003-1964-5020 dpkrabbe@usgs.gov","orcid":"https://orcid.org/0000-0003-1964-5020","contributorId":1658,"corporation":false,"usgs":true,"family":"Krabbenhoft","given":"David","email":"dpkrabbe@usgs.gov","middleInitial":"P.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true},{"id":37464,"text":"WMA - Laboratory & Analytical Services Division","active":true,"usgs":true},{"id":37947,"text":"Upper Midwest Water Science Center","active":true,"usgs":true},{"id":677,"text":"Wisconsin Water Science Center","active":true,"usgs":true}],"preferred":true,"id":684636,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Naftz, David L. 0000-0003-1130-6892 dlnaftz@usgs.gov","orcid":"https://orcid.org/0000-0003-1130-6892","contributorId":1041,"corporation":false,"usgs":true,"family":"Naftz","given":"David","email":"dlnaftz@usgs.gov","middleInitial":"L.","affiliations":[{"id":5050,"text":"WY-MT Water Science Center","active":true,"usgs":true},{"id":610,"text":"Utah Water Science Center","active":true,"usgs":true}],"preferred":true,"id":684637,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Cecil, L. DeWayne","contributorId":72828,"corporation":false,"usgs":true,"family":"Cecil","given":"L.","email":"","middleInitial":"DeWayne","affiliations":[],"preferred":false,"id":684638,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Olson, Mark L.","contributorId":149743,"corporation":false,"usgs":false,"family":"Olson","given":"Mark","email":"","middleInitial":"L.","affiliations":[{"id":17808,"text":"University of Illinois, Champaign","active":true,"usgs":false}],"preferred":false,"id":684639,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"DeWild, John F. 0000-0003-4097-2798 jfdewild@usgs.gov","orcid":"https://orcid.org/0000-0003-4097-2798","contributorId":2525,"corporation":false,"usgs":true,"family":"DeWild","given":"John","email":"jfdewild@usgs.gov","middleInitial":"F.","affiliations":[{"id":37947,"text":"Upper Midwest Water Science Center","active":true,"usgs":true},{"id":677,"text":"Wisconsin Water Science Center","active":true,"usgs":true}],"preferred":true,"id":684640,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Susong, David D. ddsusong@usgs.gov","contributorId":1040,"corporation":false,"usgs":true,"family":"Susong","given":"David","email":"ddsusong@usgs.gov","middleInitial":"D.","affiliations":[{"id":610,"text":"Utah Water Science Center","active":true,"usgs":true}],"preferred":true,"id":684641,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Green, Jaromy R.","contributorId":57498,"corporation":false,"usgs":true,"family":"Green","given":"Jaromy","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":684642,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Abbott, Michael L.","contributorId":189373,"corporation":false,"usgs":false,"family":"Abbott","given":"Michael","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":684643,"contributorType":{"id":1,"text":"Authors"},"rank":9}]}}
,{"id":70185661,"text":"70185661 - 2002 - Distribution, production, and ecophysiology of Picocystis strain ML in Mono Lake, California","interactions":[],"lastModifiedDate":"2020-01-04T13:57:24","indexId":"70185661","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"Distribution, production, and ecophysiology of Picocystis strain ML in Mono Lake, California","docAbstract":"<p>A recently described unicellular chlorophytic alga isolated from meromictic Mono Lake, California, occupies a niche that spans two environments: the upper oxic mixolimnion and the deeper anoxic and highly reducing monimolimnion. This organism, Picocystis sp. strain ML, accounts for nearly 25% of the primary production during the winter bloom and more than 50% at other times of the year. In incubations, it is heavily grazed by the brine shrimp, Artemia monica. We assessed growth and photosynthetic parameters over broad ranges of irradiance, salinity, and pH and under oxic and anoxic conditions. Picocystis appears to be particularly adapted to low irradiance; we observed an order of magnitude increase in the cellular pigment concentrations, as well as marked increases in cellspecific photosynthetic parameters for cells acclimated to low-growth irradiance. Growth rates of 0.3–1.5 d21 were observed over a salinity range of 0–260‰ and a pH range of 4–12, with maximal growth at ;50 mmol photons m22 s21 , 40‰, and pH 6–10. Growth and oxygenic photosynthesis were observed under anoxic conditions at rates comparable to those measured under oxic conditions. The ability of the organism to acclimate and grow under such a broad range of environmental conditions makes it an important component of the Mono Lake ecosystem and likely contributes to its dominance of the monimolimnion/mixolimnion interface.</p>","language":"English","publisher":" American Society of Limnology and Oceanography, Inc.","usgsCitation":"Roesler, C.S., Culbertson, C.W., Etheridge, S.M., Goericke, R., Kiene, R.P., Miller, L., and Oremland, R.S., 2002, Distribution, production, and ecophysiology of Picocystis strain ML in Mono Lake, California: Limnology and Oceanography, v. 47, no. 2, p. 440-452.","productDescription":"13 p. ","startPage":"440","endPage":"452","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":338366,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Mono Lake ","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -119.13780212402344,\n              38.03132654864846\n            ],\n            [\n              -119.16252136230467,\n              38.00536101289634\n            ],\n            [\n              -119.12132263183595,\n              37.95719224376526\n            ],\n            [\n              -118.99154663085936,\n              37.9241594356582\n            ],\n            [\n              -118.88031005859375,\n              38.01131226070673\n            ],\n            [\n              -118.92425537109375,\n              38.077284611299554\n            ],\n            [\n              -119.0375518798828,\n              38.09241741843045\n            ],\n            [\n              -119.11376953125,\n              38.036734877267705\n            ],\n            [\n              -119.13780212402344,\n              38.03132654864846\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"47","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"58da2539e4b0543bf7fda849","contributors":{"authors":[{"text":"Roesler, Collin S.","contributorId":152025,"corporation":false,"usgs":false,"family":"Roesler","given":"Collin","email":"","middleInitial":"S.","affiliations":[{"id":18855,"text":"Department of Earth and Oceanographic Science, Bowdoin College, Brunswick, ME","active":true,"usgs":false}],"preferred":false,"id":686263,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Culbertson, Charles W. cculbert@usgs.gov","contributorId":1607,"corporation":false,"usgs":true,"family":"Culbertson","given":"Charles","email":"cculbert@usgs.gov","middleInitial":"W.","affiliations":[{"id":371,"text":"Maine Water Science Center","active":true,"usgs":true}],"preferred":true,"id":686264,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Etheridge, Stacey M.","contributorId":189850,"corporation":false,"usgs":false,"family":"Etheridge","given":"Stacey","email":"","middleInitial":"M.","affiliations":[{"id":6619,"text":"University of Connecticutt","active":true,"usgs":false}],"preferred":false,"id":686265,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Goericke, Ralf","contributorId":189851,"corporation":false,"usgs":false,"family":"Goericke","given":"Ralf","email":"","affiliations":[{"id":16196,"text":"Scripps Institution of Oceanography, La Jolla, CA","active":true,"usgs":false}],"preferred":false,"id":686266,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Kiene, Ronald P.","contributorId":173346,"corporation":false,"usgs":false,"family":"Kiene","given":"Ronald","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":686267,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Miller, Laurence G. 0000-0002-7807-3475 lgmiller@usgs.gov","orcid":"https://orcid.org/0000-0002-7807-3475","contributorId":2460,"corporation":false,"usgs":true,"family":"Miller","given":"Laurence G.","email":"lgmiller@usgs.gov","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":686268,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Oremland, Ronald S. 0000-0001-7382-0147 roremlan@usgs.gov","orcid":"https://orcid.org/0000-0001-7382-0147","contributorId":931,"corporation":false,"usgs":true,"family":"Oremland","given":"Ronald","email":"roremlan@usgs.gov","middleInitial":"S.","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":686269,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}}
,{"id":70188285,"text":"70188285 - 2002 - Hydrogeologic framework, ground-water geochemistry, and assessment of nitrogen yield from base flow in two agricultural watersheds, Kent County, Maryland","interactions":[],"lastModifiedDate":"2020-02-18T19:55:03","indexId":"70188285","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":1,"text":"Federal Government Series"},"seriesNumber":"EPA/600/R-02/008","title":"Hydrogeologic framework, ground-water geochemistry, and assessment of nitrogen yield from base flow in two agricultural watersheds, Kent County, Maryland","docAbstract":"<p><span>Hydrostratigraphic and geochemical data collected in two adjacent watersheds on the Delmarva Peninsula, in Kent County, Maryland, indicate that shallow subsurface stratigraphy is an important factor that affects the concentrations of nitrogen in ground water discharging as stream base flow. The flux of nitrogen from shallow aquifers can contribute substantially to the&nbsp;</span><span>eutrophication of streams and estuaries, degrading water quality and aquatic habitats. The information presented in this report includes a hydrostratigraphic framework for the Locust Grove study area, analyses and interpretation of ground-water chemistry, and an analysis of nutrient yields from stream base flow. An understanding of the processes by which ground-water&nbsp;</span><span>nitrogen discharges to streams is important for optimal management of nutrients in watersheds in which ground-water discharge is an appreciable percentage of total streamflow. The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency (USEPA), collected and analyzed hydrostratigraphic and geochemical data in support of&nbsp;</span><span>ground-water flow modeling by the USEPA.</span><br><br><span>The adjacent watersheds of Morgan Creek and Chesterville Branch have similar topography and land use; however, reported nitrogen concentrations are generally 6 to 10 milligrams per liter in Chesterville Branch but only 2 to 4 milligrams per liter in Morgan Creek. Ground water in the surficial aquifer in the recharge areas of both streams has high concentrations of nitrate&nbsp;</span><span>(greater than 10 milligrams per liter as N) and dissolved oxygen. One component of the ground water discharging to Morgan Creek typically is anoxic and contains virtually no dissolved nitrate; most of the ground water discharging to Chesterville Branch is oxygenated and contains moderately high concentrations of nitrate.</span><br><br><span>The surficial aquifer in the study area is composed of the deeply weathered sands and gravels of the Pensauken Formation (the Columbia aquifer) and the underlying glauconitic sands of the upper Aquia Formation (the Aquia aquifer). The lower 6 to 9 meters of the Aquia Formation is a low-permeability silt-clay with abundant glauconite. The Aquia confining layer underlies&nbsp;</span><span>the Columbia-Aquia surficial aquifer throughout the study area. The sediment redox transition, identified in cores, that occurs in the upper 0.5 to 1 meter of the Aquia confining layer is thought to be a site for subsurface denitrification of ground water. The first confined aquifer is composed of the glauconitic sands in the upper 9 to 11 meters of the Hornerstown Formation. The&nbsp;</span><span>Hornerstown aquifer is underlain by 10 to 15 meters of glauconitic silt-clay at the base of the Hornerstown Formation (the Hornerstown confining layer), and 5 meters of low-permeability clay in the underlying Severn Formation.</span><br><br><span>The Aquia and Hornerstown Formations dip and thicken to the southeast, and the Aquia confining layer subcrops shallowly (within 5 meters of the land surface) in a band that strikes southwest to northeast across the northern edge of the study area. The surficial aquifer is very thin (generally less than 5 meters) north of Morgan Creek, and the alluvial valley of Morgan Creek has incised into the top of the Aquia confining layer. In contrast, the Aquia confining layer lies 22 meters below Chesterville Branch, and the surficial aquifer approaches 30 meters in thickness (away from the creek).</span><br><br><span>Chemically reduced iron sulfides and glauconite in the Aquia confining layer are likely substrates for denitrification of nitrate in ground water. Evidence from the dissolved concentrations of nitrate, sulfate, iron, argon, and nitrogen gas, and stable nitrogen isotopes support the interpretation that ground water flowing near the top of the Aquia confining layer, or through the confined Hornerstown aquifer, has undergone denitrification. This process appears to have the greatest effect on ground-water chemistry north of Morgan Creek, where the surficial aquifer is thin and a greater percentage of the ground water contacts the Aquia confining layer.</span><br><br><span>The base-flow discharges of total nitrogen from the two watersheds are of similar magnitude, although Chesterville Branch has somewhat higher loads (29,000 kilograms of nitrogen per year) than Morgan Creek (20,000 kilograms of nitrogen per year), although Morgan Creek has a larger drainage area and a greater discharge of water. The base-flow yield of nitrogen (load per unit area) in Chesterville Branch (median of 0.058 grams per second per square kilometer at the outlet) is more than twice that of Morgan Creek (median of 0.022 grams per second per square kilometer at the outlet), reflecting the higher concentration of nitrate in ground water discharging to Chesterville Branch. Total nitrogen concentrations tend to decrease downstream in&nbsp;</span><span>Chesterville Branch and increase downstream in Morgan Creek. The downstream trend in Chesterville Branch may be affected by instream nitrogen uptake and denitrification, and an increasing proportion of older, denitrified ground water in downstream discharge. The downstream trends in Morgan Creek may be affected by inflow from tributaries, downstream changes in the source of discharge water, and downstream changes in the riparian zone, which could affect the processes and degree of denitrification.</span><br><br><span>Although these two watersheds appear to have landscape features (such as topography, land use, and soils) that would produce similar nitrogen discharges, a more detailed examination of landscape features indicates that Chesterville Branch has soils that are slightly better drained, tributary stream outlets at higher altitudes, and a slightly higher percentage of agricultural land. All of these factors have been related to higher nitrogen yields. Nonetheless, most of the data support the interpretation that hydrostratigraphy has the greatest effect in producing the difference in nitrogen yields between the two watersheds.</span></p>","language":"English","publisher":"U.S. Environmental Protection Agency","publisherLocation":"Washington, D.C.","usgsCitation":"Bachman, L., Krantz, D., and Bohlke, J., 2002, Hydrogeologic framework, ground-water geochemistry, and assessment of nitrogen yield from base flow in two agricultural watersheds, Kent County, Maryland, 93 p.","productDescription":"93 p.","costCenters":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":342107,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":342106,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://cfpub.epa.gov/si/si_public_record_Report.cfm?dirEntryID=55294"}],"country":"United States","state":"Maryland","county":"Kent County","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"59366daee4b0f6c2d0d7d656","contributors":{"authors":[{"text":"Bachman, L. J.","contributorId":47760,"corporation":false,"usgs":true,"family":"Bachman","given":"L. J.","affiliations":[],"preferred":false,"id":697128,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Krantz, D.E.","contributorId":9838,"corporation":false,"usgs":true,"family":"Krantz","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":697129,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bohlke, J.K. 0000-0001-5693-6455 jkbohlke@usgs.gov","orcid":"https://orcid.org/0000-0001-5693-6455","contributorId":191103,"corporation":false,"usgs":true,"family":"Bohlke","given":"J.K.","email":"jkbohlke@usgs.gov","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":36183,"text":"Hydro-Ecological Interactions Branch","active":true,"usgs":true},{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":697130,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70188326,"text":"70188326 - 2002 - Using spring-water chemistry to assess groundwater contamination and ages of shallow and deep ground water flow systems","interactions":[],"lastModifiedDate":"2017-06-06T11:20:05","indexId":"70188326","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Using spring-water chemistry to assess groundwater contamination and ages of shallow and deep ground water flow systems","docAbstract":"<p>No abstract available.</p>","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Hydrology and biology of post-paleozoic carbonate aquifers, Karst Waters Institute Special Publication 7","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Karst Waters Institute","usgsCitation":"Katz, B.G., Bohlke, J., and Hornsby, D., 2002, Using spring-water chemistry to assess groundwater contamination and ages of shallow and deep ground water flow systems, chap. <i>of</i> Hydrology and biology of post-paleozoic carbonate aquifers, Karst Waters Institute Special Publication 7, p. 76-78.","productDescription":"3 p.","startPage":"76","endPage":"78","costCenters":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"links":[{"id":342149,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":342148,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://karstwaters.org/publications/sp7-hydrology-and-biology-of-post-paleozoic-carbonate-aquifers/"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5937bf32e4b0f6c2d0d9c7c2","contributors":{"authors":[{"text":"Katz, B. G.","contributorId":115372,"corporation":false,"usgs":true,"family":"Katz","given":"B.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":697229,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bohlke, J.K. 0000-0001-5693-6455 jkbohlke@usgs.gov","orcid":"https://orcid.org/0000-0001-5693-6455","contributorId":191103,"corporation":false,"usgs":true,"family":"Bohlke","given":"J.K.","email":"jkbohlke@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":36183,"text":"Hydro-Ecological Interactions Branch","active":true,"usgs":true}],"preferred":true,"id":697230,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hornsby, D.","contributorId":192642,"corporation":false,"usgs":false,"family":"Hornsby","given":"D.","email":"","affiliations":[],"preferred":false,"id":697231,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":1016313,"text":"1016313 - 2002 - Nutrient limitation, hydrology and watershed nitrogen loss","interactions":[],"lastModifiedDate":"2017-11-21T16:08:54","indexId":"1016313","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"Nutrient limitation, hydrology and watershed nitrogen loss","docAbstract":"<p>No abstract available.<br data-mce-bogus=\"1\"></p>","language":"English","publisher":"Wiley","doi":"10.1002/hyp.5078","usgsCitation":"Perakis, S., 2002, Nutrient limitation, hydrology and watershed nitrogen loss: Hydrological Processes, v. 16, no. 17, p. 3507-3511, https://doi.org/10.1002/hyp.5078.","productDescription":"5 p.","startPage":"3507","endPage":"3511","costCenters":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"links":[{"id":133339,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"16","issue":"17","noUsgsAuthors":false,"publicationDate":"2002-11-21","publicationStatus":"PW","scienceBaseUri":"4f4e4afce4b07f02db69676a","contributors":{"authors":[{"text":"Perakis, Steven S. 0000-0003-0703-9314","orcid":"https://orcid.org/0000-0003-0703-9314","contributorId":16797,"corporation":false,"usgs":true,"family":"Perakis","given":"Steven S.","affiliations":[],"preferred":false,"id":323968,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":1016183,"text":"1016183 - 2002 - Rangeland health attributes and indicators for qualitative assessment","interactions":[],"lastModifiedDate":"2022-08-03T15:55:45.318426","indexId":"1016183","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2441,"text":"Journal of Range Management","active":true,"publicationSubtype":{"id":10}},"title":"Rangeland health attributes and indicators for qualitative assessment","docAbstract":"Panels of experts from the Society for Range Management and the National Research Council proposed that status of rangeland ecosystems could be ascertained by evaluating an ecological site's potential to conserve soil resources and by a series of indicators for ecosystem processes and site stability. Using these recommendations as a starting point, we developed a rapid, qualitative method for assessing a moment-in-time status of rangelands. Evaluators rate 17 indicators to assess 3 ecosystem attributes (soil and site stability, hydrologic function, and biotic integrity) for a given location. Indicators include rills, water flow patterns, pedestals and terracettes, bare ground, gullies, wind scour and depositional areas, litter movement, soil resistance to erosion, soil surface loss or degradation, plant composition relative to infiltration, soil compaction, plant functional/structural groups, plant mortality, litter amount, annual production, invasive plants, and reproductive capability. In this paper, we detail the development and evolution of the technique and introduce a modified ecological reference worksheet that documents the expected presence and amount of each indicator on the ecological site. In addition, we review the intended applications for this technique and clarify the differences between assessment and monitoring that lead us to recommend this technique be used for moment-in-time assessments and not be used for temporal monitoring of rangeland status. Lastly, we propose a mechanism for adapting and modifying this technique to reflect improvements in understanding of ecosystem processes. We support the need for quantitative measures for monitoring rangeland health and propose some measures that we believe may address some of the 17 indicators.","language":"English","publisher":"Allen Press","doi":"10.2307/4004002","usgsCitation":"Pyke, D.A., Herrick, J.E., Shaver, P., and Pellant, M., 2002, Rangeland health attributes and indicators for qualitative assessment: Journal of Range Management, v. 55, no. 6, p. 584-597, https://doi.org/10.2307/4004002.","productDescription":"14 p.","startPage":"584","endPage":"597","numberOfPages":"14","costCenters":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"links":[{"id":478698,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://hdl.handle.net/10150/643703","text":"External Repository"},{"id":135440,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"55","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a80e4b07f02db6494f5","contributors":{"authors":[{"text":"Pyke, David A. 0000-0002-4578-8335 david_a_pyke@usgs.gov","orcid":"https://orcid.org/0000-0002-4578-8335","contributorId":3118,"corporation":false,"usgs":true,"family":"Pyke","given":"David","email":"david_a_pyke@usgs.gov","middleInitial":"A.","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true},{"id":289,"text":"Forest and Rangeland Ecosys Science Center","active":true,"usgs":true}],"preferred":true,"id":323688,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Herrick, Jeffrey E.","contributorId":26054,"corporation":false,"usgs":false,"family":"Herrick","given":"Jeffrey","email":"","middleInitial":"E.","affiliations":[{"id":12627,"text":"USDA-ARS Jornada Experimental Range, New Mexico State University, Las Cruces, NM 88003-8003, USA","active":true,"usgs":false}],"preferred":false,"id":323689,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shaver, Patrick","contributorId":217950,"corporation":false,"usgs":false,"family":"Shaver","given":"Patrick","affiliations":[{"id":6680,"text":"Oregon State University","active":true,"usgs":false}],"preferred":false,"id":848222,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Pellant, Mike","contributorId":97057,"corporation":false,"usgs":true,"family":"Pellant","given":"Mike","affiliations":[],"preferred":false,"id":323690,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":1015229,"text":"1015229 - 2002 - Meeting ecological and societal needs for freshwater","interactions":[],"lastModifiedDate":"2018-02-21T17:25:52","indexId":"1015229","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1450,"text":"Ecological Applications","active":true,"publicationSubtype":{"id":10}},"title":"Meeting ecological and societal needs for freshwater","docAbstract":"<p>Human society has used freshwater from rivers, lakes, groundwater, and wetlands for many different urban, agricultural, and industrial activities, but in doing so has overlooked its value in supporting ecosystems. Freshwater is vital to human life and societal well-being, and thus its utilization for consumption, irrigation, and transport has long taken precedence over other commodities and services provided by freshwater ecosystems. However, there is growing recognition that functionally intact and biologically complex aquatic ecosystems provide many economically valuable services and long-term benefits to society. The short-term benefits include ecosystem goods and services, such as food supply, flood control, purification of human and industrial wastes, and habitat for plant and animal life—and these are costly, if not impossible, to replace. Long-term benefits include the sustained provision of those goods and services, as well as the adaptive capacity of aquatic ecosystems to respond to future environmental alterations, such as climate change. Thus, maintenance of the processes and properties that support freshwater ecosystem integrity should be included in debates over sustainable water resource allocation.</p><p>The purpose of this report is to explain how the integrity of freshwater ecosystems depends upon adequate quantity, quality, timing, and temporal variability of water flow. Defining these requirements in a comprehensive but general manner provides a better foundation for their inclusion in current and future debates about allocation of water resources. In this way the needs of freshwater ecosystems can be legitimately recognized and addressed. We also recommend ways in which freshwater ecosystems can be protected, maintained, and restored.</p><p>Freshwater ecosystem structure and function are tightly linked to the watershed or catchment of which they are a part. Because riverine networks, lakes, wetlands, and their connecting groundwaters, are literally the “sinks” into which landscapes drain, they are greatly influenced by terrestrial processes, including many human uses or modifications of land and water. Freshwater ecosystems, whether lakes, wetlands, or rivers, have specific requirements in terms of quantity, quality, and seasonality of their water supplies. Sustainability normally requires these systems to fluctuate within a natural range of variation. Flow regime, sediment and organic matter inputs, thermal and light characteristics, chemical and nutrient characteristics, and biotic assemblages are fundamental defining attributes of freshwater ecosystems. These attributes impart relatively unique characteristics of productivity and biodiversity to each ecosystem. The natural range of variation in each of these attributes is critical to maintaining the integrity and dynamic potential of aquatic ecosystems; therefore, management should allow for dynamic change. Piecemeal approaches cannot solve the problems confronting freshwater ecosystems.</p><p>Scientific definitions of the requirements to protect and maintain aquatic ecosystems are necessary but insufficient for establishing the appropriate distribution between societal and ecosystem water needs. For scientific knowledge to be implemented science must be connected to a political agenda for sustainable development. We offer these recommendations as a beginning to redress how water is viewed and managed in the United States: (1) Frame national and regional water management policies to explicitly incorporate freshwater ecosystem needs, particularly those related to naturally variable flow regimes and to the linking of water quality with water quantity; (2) Define water resources to include watersheds, so that freshwaters are viewed within a landscape, or systems context; (3) Increase communication and education across disciplines, especially among engineers, hydrologists, economists, and ecologists to facilitate an integrated view of freshwater resources; (4) Increase restoration efforts, using well-grounded ecological principles as guidelines; (5) Maintain and protect the remaining freshwater ecosystems that have high integrity; and (6) Recognize the dependence of human society on naturally functioning ecosystems.</p>","language":"English","publisher":"Wiley","doi":"10.1890/1051-0761(2002)012[1247:MEASNF]2.0.CO;2","usgsCitation":"Baron, J., Poff, N., Angermeier, P., Dahm, C., Gleick, P., Hairston, N., Jackson, R., Johnston, C., Richter, B.D., and Steinman, A., 2002, Meeting ecological and societal needs for freshwater: Ecological Applications, v. 12, no. 5, p. 1247-1260, https://doi.org/10.1890/1051-0761(2002)012[1247:MEASNF]2.0.CO;2.","productDescription":"14 p.","startPage":"1247","endPage":"1260","costCenters":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"links":[{"id":132716,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"12","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a28e4b07f02db610e2b","contributors":{"authors":[{"text":"Baron, Jill 0000-0002-5902-6251 jill_baron@usgs.gov","orcid":"https://orcid.org/0000-0002-5902-6251","contributorId":194124,"corporation":false,"usgs":true,"family":"Baron","given":"Jill","email":"jill_baron@usgs.gov","affiliations":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"preferred":true,"id":322603,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Poff, N.L.","contributorId":22723,"corporation":false,"usgs":true,"family":"Poff","given":"N.L.","email":"","affiliations":[],"preferred":false,"id":322604,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Angermeier, P. L. 0000-0003-2864-170X","orcid":"https://orcid.org/0000-0003-2864-170X","contributorId":6410,"corporation":false,"usgs":true,"family":"Angermeier","given":"P. L.","affiliations":[],"preferred":false,"id":322601,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Dahm, Clifford N.","contributorId":22730,"corporation":false,"usgs":false,"family":"Dahm","given":"Clifford N.","affiliations":[{"id":7000,"text":"Department of Biology, University of New Mexico","active":true,"usgs":false}],"preferred":false,"id":322605,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Gleick, P.H.","contributorId":13935,"corporation":false,"usgs":true,"family":"Gleick","given":"P.H.","email":"","affiliations":[],"preferred":false,"id":322602,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Hairston, N.G. Jr.","contributorId":53748,"corporation":false,"usgs":true,"family":"Hairston","given":"N.G.","suffix":"Jr.","affiliations":[],"preferred":false,"id":322609,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Jackson, R.B.","contributorId":42174,"corporation":false,"usgs":true,"family":"Jackson","given":"R.B.","email":"","affiliations":[],"preferred":false,"id":322606,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Johnston, C.A.","contributorId":42175,"corporation":false,"usgs":true,"family":"Johnston","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":322607,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Richter, B. D.","contributorId":48518,"corporation":false,"usgs":true,"family":"Richter","given":"B.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":322608,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Steinman, A.D.","contributorId":65433,"corporation":false,"usgs":true,"family":"Steinman","given":"A.D.","email":"","affiliations":[],"preferred":false,"id":322610,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}}
,{"id":1000945,"text":"1000945 - 2002 - Hydrologic variability and the application of Index of Biotic Integrity metrics to wetlands: a Great Lakes evaluation","interactions":[],"lastModifiedDate":"2016-05-23T10:10:38","indexId":"1000945","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","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":"Hydrologic variability and the application of Index of Biotic Integrity metrics to wetlands: a Great Lakes evaluation","docAbstract":"<p>Interest by land-management and regulatory agencies in using biological indicators to detect wetland degradation, coupled with ongoing use of this approach to assess water quality in streams, led to the desire to develop and evaluate an Index of Biotic Integrity (IBI) for wetlands that could be used to categorize the level of degradation. We undertook this challenge with data from coastal wetlands of the Great Lakes, which have been degraded by a variety of human disturbances. We studied six barrier beach wetlands in western Lake Superior, six drowned-river-mouth wetlands along the eastern shore of Lake Michigan, and six open shoreline wetlands in Saginaw Bay of Lake Huron. Plant, fish, and invertebrate communities were sampled in each wetland. The resulting data were assessed in various forms against gradients of human disturbance to identify potential metrics that could be used in IBI development. Our results suggested that the metrics proposed as potential components of an IBI for barrier beach wetlands of Lake Superior held promise. The metrics for Lake Michigan drowned-river-mouth wetlands were inconsistent in identifying gradients of disturbance; those for Lake Huron open embayment wetlands were yet more inconsistent. Despite the potential displayed by the Lake Superior results within the year sampled, we concluded that an IBI for use in Great Lakes wetlands would not be valid unless separate scoring ranges were derived for each of several sequences of water-level histories. Variability in lake levels from year to year can produce variability in data and affect the reproducibility of data collected, primarily due to extreme changes in plant communities and the faunal habitat they provide. Substantially different results could be obtained in the same wetland in different years as a result of the response to lake-level change, with no change in the level of human disturbance. Additional problems included limited numbers of comparable sites, potential lack of undisturbed reference sites, and variable effects of different disturbance types. We also evaluated our conclusions with respect to hydrologic variability and other major natural disturbances affecting wetlands in other regions. We concluded that after segregation of wetland types by geographic, geomorphic, and hydrologic features, a functional IBI may be possible for wetlands with relatively stable hydrology. However, an IBI for wetlands with unpredictable yet recurring influences of climate-induced, long-term high water periods, droughts, or drought-related fires or weather-related catastrophic floods or high winds (hurricanes) would also require differing scales of measurement for years that differ in the length of time since the last major natural disturbance. A site-specific, detailed ecological analysis of biological indicators may indeed be of value in determining the quality or status of wetlands, but we recommend that IBI scores not be used unless the scoring ranges are calibrated for the specific hydrologic history pre-dating any sampling year.</p>","language":"English","publisher":"The Society of Wetland Scientists","doi":"10.1672/0277-5212(2002)022[0588:HVATAO]2.0.CO;2","usgsCitation":"Wilcox, D.A., Meeker, J.E., Hudson, P.L., Armitage, B.J., Black, M.G., and Uzarski, D.G., 2002, Hydrologic variability and the application of Index of Biotic Integrity metrics to wetlands: a Great Lakes evaluation: Wetlands, v. 22, no. 3, p. 588-615, https://doi.org/10.1672/0277-5212(2002)022[0588:HVATAO]2.0.CO;2.","productDescription":"28 p.","startPage":"588","endPage":"615","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":478682,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://hdl.handle.net/20.500.12648/2298","text":"External Repository"},{"id":133581,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"22","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4acce4b07f02db67e9b3","contributors":{"authors":[{"text":"Wilcox, Douglas A.","contributorId":36880,"corporation":false,"usgs":true,"family":"Wilcox","given":"Douglas","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":309926,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Meeker, James E.","contributorId":80228,"corporation":false,"usgs":true,"family":"Meeker","given":"James","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":309929,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hudson, Patrick L. 0000-0002-7646-443X phudson@usgs.gov","orcid":"https://orcid.org/0000-0002-7646-443X","contributorId":5616,"corporation":false,"usgs":true,"family":"Hudson","given":"Patrick","email":"phudson@usgs.gov","middleInitial":"L.","affiliations":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"preferred":true,"id":309925,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Armitage, Brian J.","contributorId":59747,"corporation":false,"usgs":true,"family":"Armitage","given":"Brian","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":309928,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Black, M. Glen gblack@usgs.gov","contributorId":2394,"corporation":false,"usgs":true,"family":"Black","given":"M.","email":"gblack@usgs.gov","middleInitial":"Glen","affiliations":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"preferred":true,"id":309924,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Uzarski, Donald G.","contributorId":44510,"corporation":false,"usgs":true,"family":"Uzarski","given":"Donald","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":309927,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}}
,{"id":70175050,"text":"70175050 - 2002 - The evolving benthic community","interactions":[],"lastModifiedDate":"2018-09-12T07:13:21","indexId":"70175050","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":9,"text":"Other Report"},"title":"The evolving benthic community","docAbstract":"<p>No abstract available.</p>","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Science and strategies for restoration","largerWorkSubtype":{"id":9,"text":"Other Report"},"language":"English","publisher":"San Francisco Estuary Project","usgsCitation":"Thompson, J.K., 2002, The evolving benthic community, 2 p.","productDescription":"2 p.","startPage":"66","endPage":"67","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":325733,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5799db7ee4b0589fa1c7eb68","contributors":{"authors":[{"text":"Thompson, Janet K. 0000-0002-1528-8452 jthompso@usgs.gov","orcid":"https://orcid.org/0000-0002-1528-8452","contributorId":1009,"corporation":false,"usgs":true,"family":"Thompson","given":"Janet","email":"jthompso@usgs.gov","middleInitial":"K.","affiliations":[{"id":36183,"text":"Hydro-Ecological Interactions Branch","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":643721,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70023857,"text":"70023857 - 2002 - Enhanced CAH dechlorination in a low permeability, variably-saturated medium","interactions":[],"lastModifiedDate":"2012-03-12T17:20:01","indexId":"70023857","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Enhanced CAH dechlorination in a low permeability, variably-saturated medium","docAbstract":"An innovative pilot-scale field test was performed to enhance the anaerobic reductive dechlorination (ARD) of chlorinated aliphatic hydrocarbons (CAHs) in a low permeability, variably-saturated formation. The selected technology combines the use of a hydraulic fracturing (fracking) technique with enhanced bioremediation through the creation of highly-permeable sand- and electron donor-filled fractures in the low permeability matrix. Chitin was selected as the electron donor because of its unique properties as a polymeric organic material and based on the results of lab studies that indicated its ability to support ARD. The distribution and impact of chitin- and sand-filled fractures to the system was evaluated using hydrologic, geophysical, and geochemical parameters. The results indicate that, where distributed, chitin favorably impacted redox conditions and supported enhanced ARD of CAHs. These results indicate that this technology may be a viable and cost-effective approach for remediation of low-permeability, variably saturated systems.","largerWorkTitle":"Proceedings of the Third International Conference on Remediation of Chlorinated and Recalcitrant Compounds","conferenceTitle":"Proceedings of the Third International Conference on Remediation of Chlorinated and Recalcitrant Compounds","conferenceDate":"20 May 2002 through 23 May 2002","conferenceLocation":"Monterey, CA.","language":"English","isbn":"1574771329","usgsCitation":"Martin, J., Sorenson, K., Peterson, L., Brennan, R., Werth, C., Sanford, R., Bures, G., and Taylor, C., 2002, Enhanced CAH dechlorination in a low permeability, variably-saturated medium, <i>in</i> Proceedings of the Third International Conference on Remediation of Chlorinated and Recalcitrant Compounds, Monterey, CA., 20 May 2002 through 23 May 2002, p. 995-1003.","startPage":"995","endPage":"1003","numberOfPages":"9","costCenters":[],"links":[{"id":231820,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a096ae4b0c8380cd51ed3","contributors":{"editors":[{"text":"Gavaskar A.R.Chen A.S.C.","contributorId":128403,"corporation":true,"usgs":false,"organization":"Gavaskar A.R.Chen A.S.C.","id":536515,"contributorType":{"id":2,"text":"Editors"},"rank":1}],"authors":[{"text":"Martin, J.P.","contributorId":30875,"corporation":false,"usgs":true,"family":"Martin","given":"J.P.","email":"","affiliations":[],"preferred":false,"id":399078,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sorenson, K.S. Jr.","contributorId":71835,"corporation":false,"usgs":true,"family":"Sorenson","given":"K.S.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":399080,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Peterson, L.N.","contributorId":85045,"corporation":false,"usgs":true,"family":"Peterson","given":"L.N.","email":"","affiliations":[],"preferred":false,"id":399081,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Brennan, R.A.","contributorId":105598,"corporation":false,"usgs":true,"family":"Brennan","given":"R.A.","email":"","affiliations":[],"preferred":false,"id":399082,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Werth, C.J.","contributorId":26481,"corporation":false,"usgs":true,"family":"Werth","given":"C.J.","affiliations":[],"preferred":false,"id":399077,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Sanford, R.A.","contributorId":6722,"corporation":false,"usgs":true,"family":"Sanford","given":"R.A.","email":"","affiliations":[],"preferred":false,"id":399075,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Bures, G.H.","contributorId":48827,"corporation":false,"usgs":true,"family":"Bures","given":"G.H.","email":"","affiliations":[],"preferred":false,"id":399079,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Taylor, C.J.","contributorId":22337,"corporation":false,"usgs":true,"family":"Taylor","given":"C.J.","email":"","affiliations":[],"preferred":false,"id":399076,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}}
,{"id":70175192,"text":"70175192 - 2002 - A comment on the use of flushing time, residence time, and age as transport time scales","interactions":[],"lastModifiedDate":"2018-11-28T07:49:25","indexId":"70175192","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2620,"text":"Limnology and Oceanography","active":true,"publicationSubtype":{"id":10}},"title":"A comment on the use of flushing time, residence time, and age as transport time scales","docAbstract":"<p><span>Applications of transport time scales are pervasive in biological, hydrologic, and geochemical studies yet these times scales are not consistently defined and applied with rigor in the literature. We compare three transport time scales (flushing time, age, and residence time) commonly used to measure the retention of water or scalar quantities transported with water. We identify the underlying assumptions associated with each time scale, describe procedures for computing these time scales in idealized cases, and identify pitfalls when real-world systems deviate from these idealizations. We then apply the time scale definitions to a shallow 378 ha tidal lake to illustrate how deviations between real water bodies and the idealized examples can result from: (1) non-steady flow; (2) spatial variability in bathymetry, circulation, and transport time scales; and (3) tides that introduce complexities not accounted for in the idealized cases. These examples illustrate that no single transport time scale is valid for all time periods, locations, and constituents, and no one time scale describes all transport processes. We encourage aquatic scientists to rigorously define the transport time scale when it is applied, identify the underlying assumptions in the application of that concept, and ask if those assumptions are valid in the application of that approach for computing transport time scales in real systems.</span></p>","language":"English","publisher":"ASLO","doi":"10.4319/lo.2002.47.5.1545","usgsCitation":"Monsen, N.E., Cloern, J.E., Lucas, L.V., and Monismith, S., 2002, A comment on the use of flushing time, residence time, and age as transport time scales: Limnology and Oceanography, v. 47, no. 5, p. 1545-1553, https://doi.org/10.4319/lo.2002.47.5.1545.","productDescription":"9 p.","startPage":"1545","endPage":"1553","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":478670,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.4319/lo.2002.47.5.1545","text":"Publisher Index Page"},{"id":325925,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"47","issue":"5","noUsgsAuthors":false,"publicationDate":"2002-09-06","publicationStatus":"PW","scienceBaseUri":"57a1c42ce4b006cb45552be2","contributors":{"authors":[{"text":"Monsen, Nancy E.","contributorId":173324,"corporation":false,"usgs":false,"family":"Monsen","given":"Nancy","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":644283,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cloern, James E. 0000-0002-5880-6862 jecloern@usgs.gov","orcid":"https://orcid.org/0000-0002-5880-6862","contributorId":1488,"corporation":false,"usgs":true,"family":"Cloern","given":"James","email":"jecloern@usgs.gov","middleInitial":"E.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":true,"id":644284,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lucas, Lisa V.","contributorId":80992,"corporation":false,"usgs":true,"family":"Lucas","given":"Lisa","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":644285,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Monismith, Stephen G.","contributorId":57228,"corporation":false,"usgs":true,"family":"Monismith","given":"Stephen G.","affiliations":[],"preferred":false,"id":644286,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70174921,"text":"70174921 - 2002 - United States streamflow probabilities and uncertainties based on anticipated El Niño, water year 2003","interactions":[],"lastModifiedDate":"2016-07-28T15:15:14","indexId":"70174921","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":5147,"text":"Experimental Long-Lead Forecast Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"United States streamflow probabilities and uncertainties based on anticipated El Niño, water year 2003","docAbstract":"<p>During the course of spring and summer 2002, tropical sea-surface temperatures in the eastern Pacific Ocean have warmed and the wind and pressure fields have shifted, so that by August, there was considerable confidence that water year (October&ndash;September) 2003 will be characterized by a weak to mild El Ni&ntilde;o climate (http://iri.columbia.edu/climate/ENSO/currentinfo/archive/200208/QuickLook.html). At the same time, the Pacific Decadal Oscillation pattern of sea-surface temperatures in the North Pacific (Mantua et al., 1997) has shifted towards a more neutral state than in the past several years and will not be considered in detail here. Previous studies of the connections between El Ni&ntilde;os and streamflow in the United States by the authors (e.g., Redmond and Koch, 1991; Cayan and Webb, 1992; Cayan et al., 1999; Dettinger et al., 2001) indicate that El Ni&ntilde;o conditions influence historical streamflow distributions to varying extents. These conclusions, along with those of other researchers, suggest that foreknowledge of El Ni&ntilde;o conditions can inform seasonal outlooks for streamflows throughout the Americas and elsewhere. For example, Dettinger et al. (2001), as distilled here into Fig. 1, showed that historical annual streamflow totals have correlated negatively with the Southern Oscillation Index (SOI, which is negatively associated with El Ni&ntilde;os) in the U.S. Southwest as well as in the subtropics of South America, and correlate positively in the U.S. Northwest, in much of tropical South America, and, perhaps, in southernmost South America. These interhemispheric bands of El Ni&ntilde;o influence are a matter of considerable concern for water- and land-managers throughout the Americas, and expand upon results from previous studies in the western United States (e.g., Redmond and Koch, 1991; Cayan and Webb, 1992), including a recent analysis by Pizarro and Lall (2002), where water availability and hydrologic extremes are particularly pressing issues.</p>","language":"English","usgsCitation":"Dettinger, M., Cayan, D., and Redmond, K., 2002, United States streamflow probabilities and uncertainties based on anticipated El Niño, water year 2003: Experimental Long-Lead Forecast Bulletin, v. 11, no. 3, p. 46-52.","productDescription":"7 p.","startPage":"46","endPage":"52","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":325523,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"11","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5791f234e4b0a1ebd3ad4ca5","contributors":{"authors":[{"text":"Dettinger, M. 0000-0002-7509-7332","orcid":"https://orcid.org/0000-0002-7509-7332","contributorId":78909,"corporation":false,"usgs":true,"family":"Dettinger","given":"M.","affiliations":[],"preferred":false,"id":643150,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cayan, D.","contributorId":49563,"corporation":false,"usgs":true,"family":"Cayan","given":"D.","email":"","affiliations":[],"preferred":false,"id":643151,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Redmond, K.","contributorId":48355,"corporation":false,"usgs":true,"family":"Redmond","given":"K.","email":"","affiliations":[],"preferred":false,"id":643152,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":87280,"text":"87280 - 2002 - Conservation and restoration of semi-arid riparian forests: A case study from the Upper Missouri River, Montana","interactions":[],"lastModifiedDate":"2017-12-22T18:03:52","indexId":"87280","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Conservation and restoration of semi-arid riparian forests: A case study from the Upper Missouri River, Montana","docAbstract":"<p>No abstract available.<br data-mce-bogus=\"1\"></p>","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Flood pulsing in wetlands: Restoring the natural hydrological balance","largerWorkSubtype":{"id":4,"text":"Other Government Series"},"language":"English","publisher":"John Wiley & Sons, Inc.","isbn":"978-0471418078","usgsCitation":"Scott, M.L., and Auble, G., 2002, Conservation and restoration of semi-arid riparian forests: A case study from the Upper Missouri River, Montana, chap. <i>of</i> Flood pulsing in wetlands: Restoring the natural hydrological balance, p. 145-190.","productDescription":"46 p.","startPage":"145","endPage":"190","costCenters":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"links":[{"id":127720,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":14738,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://www.wiley.com/en-us/Flood+Pulsing+in+Wetlands%3A+Restoring+the+Natural+Hydrological+Balance-p-9780471418078"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b13e4b07f02db6a30e9","contributors":{"editors":[{"text":"Middleton, Beth A. 0000-0002-1220-2326 middletonb@usgs.gov","orcid":"https://orcid.org/0000-0002-1220-2326","contributorId":2029,"corporation":false,"usgs":true,"family":"Middleton","given":"Beth","email":"middletonb@usgs.gov","middleInitial":"A.","affiliations":[{"id":17705,"text":"Wetland and Aquatic Research Center","active":true,"usgs":true}],"preferred":true,"id":504907,"contributorType":{"id":2,"text":"Editors"},"rank":1}],"authors":[{"text":"Scott, M. L.","contributorId":75090,"corporation":false,"usgs":true,"family":"Scott","given":"M.","middleInitial":"L.","affiliations":[],"preferred":false,"id":297568,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Auble, G.T.","contributorId":19505,"corporation":false,"usgs":true,"family":"Auble","given":"G.T.","email":"","affiliations":[],"preferred":false,"id":297567,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":44965,"text":"wri024032 - 2002 - Comparison of the hydrogeology and water quality of a ground-water augmented lake with two non-augmented lakes in northwest Hillsborough County, Florida","interactions":[],"lastModifiedDate":"2023-04-07T19:19:44.229929","indexId":"wri024032","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"2002-4032","title":"Comparison of the hydrogeology and water quality of a ground-water augmented lake with two non-augmented lakes in northwest Hillsborough County, Florida","docAbstract":"<p>The hydrologic effects associated with augmenting a lake with ground water from the Upper Floridan aquifer were examined in northwest Hillsborough County, Florida, from June 1996 through May 1999. The hydrogeology, ground-water flow patterns, water budgets, and water-quality characteristics were compared between a lake that has been augmented for more than 30 years (Round Lake) and two nearby nonaugmented lakes (Dosson Lake and Halfmoon Lake). </p><p>Compared to the other study lakes, Round Lake is in a more leakage-dominated hydrogeologic setting. The intermediate confining unit is thin or highly breached, which increases the potential for vertical ground-water flow. Round Lake has the least amount of soft, organic lake-bottom sediments and the lake bottom has been dredged deeper and more extensively than the other study lakes, which could allow more leakage from the lake bottom. The area around Round Lake has experienced more sinkhole activity than the other study lakes. During this study, three sinkholes developed around the perimeter of the lake, which may have further disrupted the intermediate confining unit.</p><p>Ground-water flow patterns around Round Lake were considerably different than the nonaugmented lakes. For most of the study, groundwater augmentation artificially raised the level of Round Lake to about 2 to 3 feet higher than the adjacent water table. As a result, lake water recharged the surficial aquifer around the entire lake perimeter, except during very wet periods when ground-water inflow occurred around part of the lake perimeter. The non-augmented lakes typically had areas of ground-water inflow and areas of lake leakage around their perimeter, and during wet periods, ground-water inflow occurred around the entire lake perimeter. Therefore, the area potentially contributing ground water to the non-augmented lakes is much larger than for augmented Round Lake. Vertical head loss within the surficial aquifer was greater at Round Lake than the other study lakes, which is additional evidence of the limited confinement at Round Lake. </p><p>A comparison of the water quality and lake-bottom sediments at the three lakes indicate that Round Lake is strongly influenced by the addition of large quantities of calcium-bicarbonate enriched augmentation water. Round Lake had higher alkalinity, pH, calcium and dissolved oxygen concentrations, specific conductance, and water clarity than the two non-augmented lakes. Round Lake was generally saturated to supersaturated with respect to calcite, but was undersaturated when augmentation was low and after high rainfall periods.&nbsp;Calcium carbonate has accumulated in the lake sediments from calcite precipitation, from macrophytes such as <i>Nitella</i> sp., and from the deposition of carbonate-rich mollusk shells, such as<i> Planerbella</i> sp., both of which thrive in the high alkalinity lake water. Lake-bottom sediments and aquatic biota at Round Lake had some of the highest radium-226 activity levels measured in a Florida lake. The high radium-226 levels (27 disintegrations per minute per dry mass) can be atrributed to augmenting the lake with ground water from the Upper Floridan aquifer. Although the ground water has relatively low levels of radium-226 (5.8 disintegrations per minute per liter), the large volumes of ground water added to the lake for more than 30 years have caused radium-226 to accumulate in the sediments and lake biota.</p><p>The Round Lake basin had higher calcium and bicarbonate concentrations in the surficial aquifer than at the non-augmented lakes, which indicates the lateral leakage of calcium-bicarbonate enriched lake water into the surficial aquifer. Deuterium and oxygen-18 data indicated that water in well nests near the lake consists of as much as 100 percent lake leakage, and water from the augmentation well had a high percentage of recirculated lake water (between 59 and 73 percent lake leakage). The ground water surrounding Round Lake was undersaturated with respect to calcite, indicating that the water is capable of dissolving calcite in the underlying limestone aquifer. </p><p>Annual and monthly ground-water outflow (lake leakage) was significantly higher at Round Lake than at the non-augmented lakes for the 3-year study period. Minimum estimates of the total annual ground-water inflow and outflow were made from monthly net ground-water flow values. Based on these estimates, total annual groundwater outflow from Round Lake was more than 10 times higher than for the non-augmented lakes. Local ground-water pumping, augmentation, and hydrogeologic factors are responsible for the high net ground-water outflow at Round Lake. Localized ground-water pumping causes the head difference between the lake and the Upper Floridan aquifer to increase, which increases lake leakage and results in lower lake levels. Augmenting the&nbsp;lake further increases the head difference between the lake, the water table, and the Upper Floridan aquifer, which results in an increase in lateral and vertical lake leakage. The lack of confinement or breaches in the intermediate confining unit facilitates the downward movement of this augmented lake water back into the Upper Floridan aquifer. The increase in ground-water circulation in the leakage-dominated hydrogeologic setting at Round Lake has made the basin more susceptible to karst activity (limestone dissolution, subsidence, and sinkhole formation)</p>","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri024032","collaboration":"Prepared in cooperation with the Southwest Florida Water Management District","usgsCitation":"Metz, P.A., and Sacks, L.A., 2002, Comparison of the hydrogeology and water quality of a ground-water augmented lake with two non-augmented lakes in northwest Hillsborough County, Florida: U.S. Geological Survey Water-Resources Investigations Report 2002-4032, vi, 74 p., https://doi.org/10.3133/wri024032.","productDescription":"vi, 74 p.","costCenters":[{"id":270,"text":"FLWSC-Tampa","active":true,"usgs":true}],"links":[{"id":161519,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":3839,"rank":3,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.water.usgs.gov/wri024032","linkFileType":{"id":5,"text":"html"}},{"id":415454,"rank":4,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_51961.htm","linkFileType":{"id":5,"text":"html"}},{"id":345248,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://fl.water.usgs.gov/PDF_files/wri02_4032_metz.pdf","text":"Report","linkFileType":{"id":1,"text":"pdf"},"description":"Report"}],"country":"United States","state":"Florida","county":"Hillsborough County","otherGeospatial":"Dosson Lake, Halfmoon Lake, Round Lake","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -82.5667,\n              28.085\n            ],\n            [\n              -82.483333,\n              28.085\n            ],\n            [\n              -82.483333,\n              28.1333\n            ],\n            [\n              -82.5667,\n              28.1333\n            ],\n            [\n              -82.5667,\n              28.085\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b1fe4b07f02db6ab7e1","contributors":{"authors":[{"text":"Metz, Patricia A. pmetz@usgs.gov","contributorId":1095,"corporation":false,"usgs":true,"family":"Metz","given":"Patricia","email":"pmetz@usgs.gov","middleInitial":"A.","affiliations":[{"id":270,"text":"FLWSC-Tampa","active":true,"usgs":true}],"preferred":true,"id":230785,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sacks, Laura A.","contributorId":19134,"corporation":false,"usgs":true,"family":"Sacks","given":"Laura","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":230786,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70024802,"text":"70024802 - 2002 - Source water partitioning as a means of characterizing hydrologic function in mangroves","interactions":[],"lastModifiedDate":"2012-03-12T17:20:07","indexId":"70024802","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3751,"text":"Wetlands Ecology and Management","active":true,"publicationSubtype":{"id":10}},"title":"Source water partitioning as a means of characterizing hydrologic function in mangroves","docAbstract":"Mangrove ecosystems rely on seawater, rain-derived flow, and groundwater for hydrologic sustenance, flushing, and inflow of nutrients and sediments. The relative contribution of these source waters and their variability through time and space can provide key information concerning the hydrologic function of ecosystems. We used hydrologic tracers to partition source waters and trace their movements in the Enipoas stream, a river-dominated mangrove ecosystem on the island of Pohnpei, Federated States of Micronesia (FSM) and in the Yela watershed, an interior mangrove ecosystem on the island of Kosrae, FSM. The Enipoas site was characterized as a salt wedge estuary whose source water contributions alternated between predominantly seawater and rain-derived flow, depending on the tide. The source waters in the interior Yela site were also predominantly seawater and rain-derived flow, however the relative contribution of each was much more stable. The mean groundwater contribution was 5% (SD = 5.5) for the Enipoas site and 20% (SD = 11.0) for the Yela site. Although a small contributor to flow, groundwater was a steady source of freshwater for both systems. Hydrologic linkages between mangroves and adjacent ecosystems were demonstrated by the temporal and spatial distribution of source waters. The 0.8 km Enipoas estuary, with its highly dynamic bi-directional flows, transported source waters along a hydrologic continuum comprised of coral reef, mangroves, and palm forest. In the interior mangroves of the Yela watershed, the presence of rain-derived flow and groundwater demonstrated a hydraulic connection between the mangroves and an upstream freshwater swamp. Interior mangroves with such linkages avoid stresses such as desiccation and heightened salinity, and thus are more productive than those with little or no freshwater flows.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wetlands Ecology and Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/A:1016547103966","issn":"09234861","usgsCitation":"Drexler, J., and De Carlo, E.W., 2002, Source water partitioning as a means of characterizing hydrologic function in mangroves: Wetlands Ecology and Management, v. 10, no. 2, p. 103-113, https://doi.org/10.1023/A:1016547103966.","startPage":"103","endPage":"113","numberOfPages":"11","costCenters":[],"links":[{"id":207984,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1016547103966"},{"id":233320,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b933ee4b08c986b31a3bd","contributors":{"authors":[{"text":"Drexler, J.Z. 0000-0002-0127-3866","orcid":"https://orcid.org/0000-0002-0127-3866","contributorId":54766,"corporation":false,"usgs":true,"family":"Drexler","given":"J.Z.","affiliations":[],"preferred":false,"id":402672,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"De Carlo, E. W.","contributorId":10201,"corporation":false,"usgs":true,"family":"De Carlo","given":"E.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":402671,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70025115,"text":"70025115 - 2002 - Influence of hydrologic processes on reproduction of the introduced bivalve Potamocorbula amurensis in northern San Francisco Bay, California","interactions":[],"lastModifiedDate":"2022-08-15T16:32:36.146859","indexId":"70025115","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2990,"text":"Pacific Science","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Influence of hydrologic processes on reproduction of the introduced bivalve <i>Potamocorbula amurensis</i> in northern San Francisco Bay, California","title":"Influence of hydrologic processes on reproduction of the introduced bivalve Potamocorbula amurensis in northern San Francisco Bay, California","docAbstract":"<p><span>Monthly censusing of reproductive condition of the Asian clam&nbsp;</span><i>Potamocorbula amurensis</i><span>&nbsp;at four sites in northern San Francisco Bay over a 9-yr period revealed year-to-year differences in local reproductive activity that are associated with patterns of hydrologic variability. Between 1989 and 1992, Northern California experienced a drought, whereas the period between 1993 and 1998 was marked by a mix of wet and dry years. We took advantage of the extreme year-to-year differences to examine reproductive responses to river inflow patterns. Populations of&nbsp;</span><i>P. amurensis</i><span>&nbsp;at the upstream sites in Suisun Bay and Carquinez Strait were more reproductively active during wet years than dry years. Conversely, at the downstream site in San Pablo Bay, the population was more reproductively active during dry years than wet years. We suggest that the different reproductive patterns observed reflect the clam's response to different sources of food. During wet years, organic matter from the rivers augments food supplies in Suisun Bay. During dry years, when inflow into the San Francisco Bay Estuary from the rivers is reduced, water transported from the adjacent ocean into the estuary as far as San Pablo Bay provides a supplemental food supply for the local production. The populations take advantage of these spatially distinct food supplies by initiating and maintaining local reproductive activity. We conclude that the ability of&nbsp;</span><i>P. amurensis</i><span>&nbsp;to consume and use various types of food to regulate its reproductive activity is part of the reason for its success as an invasive species.</span></p>","language":"English","publisher":"University of Hawaii Press","doi":"10.1353/psc.2002.0027","usgsCitation":"Parchaso, F., and Thompson, J.K., 2002, Influence of hydrologic processes on reproduction of the introduced bivalve Potamocorbula amurensis in northern San Francisco Bay, California: Pacific Science, v. 56, no. 3, p. 329-345, https://doi.org/10.1353/psc.2002.0027.","productDescription":"17 p.","startPage":"329","endPage":"345","numberOfPages":"17","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":478800,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"http://hdl.handle.net/10125/2569","text":"External Repository"},{"id":235722,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"northern San Francisco Bay","geographicExtents":"{\n  \"type\": \"FeatureCollection\",\n  \"features\": [\n    {\n      \"type\": \"Feature\",\n      \"properties\": {},\n      \"geometry\": {\n        \"type\": \"Polygon\",\n        \"coordinates\": [\n          [\n            [\n              -122.61016845703124,\n              37.794592824285104\n            ],\n            [\n              -121.92626953124999,\n              37.794592824285104\n            ],\n            [\n              -121.92626953124999,\n              38.236022799686694\n            ],\n            [\n              -122.61016845703124,\n              38.236022799686694\n            ],\n            [\n              -122.61016845703124,\n              37.794592824285104\n            ]\n          ]\n        ]\n      }\n    }\n  ]\n}","volume":"56","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3b43e4b0c8380cd62393","contributors":{"authors":[{"text":"Parchaso, Francis 0000-0002-9471-7787 parchaso@usgs.gov","orcid":"https://orcid.org/0000-0002-9471-7787","contributorId":150620,"corporation":false,"usgs":true,"family":"Parchaso","given":"Francis","email":"parchaso@usgs.gov","affiliations":[{"id":37464,"text":"WMA - Laboratory & Analytical Services Division","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":36183,"text":"Hydro-Ecological Interactions Branch","active":true,"usgs":true}],"preferred":true,"id":403879,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Thompson, Janet K. 0000-0002-1528-8452 jthompso@usgs.gov","orcid":"https://orcid.org/0000-0002-1528-8452","contributorId":1009,"corporation":false,"usgs":true,"family":"Thompson","given":"Janet","email":"jthompso@usgs.gov","middleInitial":"K.","affiliations":[{"id":36183,"text":"Hydro-Ecological Interactions Branch","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":403880,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70025113,"text":"70025113 - 2002 - Spatial and statistical differences between 1:250,000- and 1:24,000-scale digital soil databases","interactions":[],"lastModifiedDate":"2012-03-12T17:20:28","indexId":"70025113","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2456,"text":"Journal of Soil and Water Conservation","active":true,"publicationSubtype":{"id":10}},"title":"Spatial and statistical differences between 1:250,000- and 1:24,000-scale digital soil databases","docAbstract":"In this study, 1:250,000- and 1:24,000-scale digital soil databases for Kansas were compared statistically and spatially. The soil attributes used in this comparison were soil permeability, percent clay, and hydrologic group. Results indicate that, although the two databases were correlated, the potential exists for substantial site-specific variability between them. The largest differences between the two databases typically are in and along the stream networks. With distance away from the stream networks, the mean differences generally stabilize. The results also indicate the possibility of systematic bias between the two databases that varies with landscape position. For applications using mean soil attribute values, the two soil databases usually yield similar values for the three soil attributes analyzed, especially for areas of 25 km2 (9.7 mi2) or larger. However, for applications where more detailed information on soil variability and the spatial pattern of soil properties within the landscape is required, such as for studies focused on small areas or areas in and along stream networks, the two soil databases are sufficiently different such that using one or the other may result in substantially different results.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Soil and Water Conservation","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"00224561","usgsCitation":"Juracek, K.E., and Wolock, D., 2002, Spatial and statistical differences between 1:250,000- and 1:24,000-scale digital soil databases: Journal of Soil and Water Conservation, v. 57, no. 2, p. 89-94.","startPage":"89","endPage":"94","numberOfPages":"6","costCenters":[],"links":[{"id":235684,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"57","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9430e4b08c986b31a900","contributors":{"authors":[{"text":"Juracek, K. E. 0000-0002-2102-8980","orcid":"https://orcid.org/0000-0002-2102-8980","contributorId":44570,"corporation":false,"usgs":true,"family":"Juracek","given":"K.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":403876,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wolock, D.M. 0000-0002-6209-938X","orcid":"https://orcid.org/0000-0002-6209-938X","contributorId":36601,"corporation":false,"usgs":true,"family":"Wolock","given":"D.M.","affiliations":[],"preferred":false,"id":403875,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
,{"id":70025105,"text":"70025105 - 2002 - Evaluating the influence of source basins on downstream water quality in the Mississippi River","interactions":[],"lastModifiedDate":"2018-11-26T11:11:02","indexId":"70025105","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Evaluating the influence of source basins on downstream water quality in the Mississippi River","docAbstract":"<p><span>Chemical variability in the Mississippi River during water years 1989 to 1998 was evaluated using stream discharge and water‐quality data in conjunction with the DAFLOW/BLTM hydraulic model. Model simulations were used to identify subbasin contributions of water and chemical constituents to the Mississippi River upstream from its confluence with the Ohio and the Mississippi River and at the Atchafalaya Diversion in Louisiana. Concentrations of dissolved solids, sodium, and sulfate at the Thebes site showed a general decreasing trend, and concentrations of silica and nitrate showed a general increasing trend as the percentage of discharge from the Mississippi River upstream from Grafton increased. Concentrations of most chemical constituents in the Mississippi River at the Atchafalaya Diversion exhibited a decreasing trend as the percentage of water from the Ohio River increased. Regression models were used to evaluate the importance of the source of water to the water chemistry in the Mississippi River at Thebes and the Atchafalaya Diversion. The addition of terms in regression equations to account for the percent of water from sub‐basins improved coefficients of determination for predicting chemical concentrations by as much as nine percent at the Thebes site and by as much as 48 percent at the Atchafalaya Diversion site. The addition of source‐water terms to regression equations increased the estimated annual loads of nitrate and silica delivered from the Mississippi River Basin to the Gulf of Mexico by as much as 14 and 13 percent, respectively.</span></p>","language":"English","publisher":"Wiley","doi":"10.1111/j.1752-1688.2002.tb00998.x","issn":"1093474X","usgsCitation":"Clark, G.M., Broshears, R.E., Hooper, R.P., and Goolsby, D.A., 2002, Evaluating the influence of source basins on downstream water quality in the Mississippi River: Journal of the American Water Resources Association, v. 38, no. 3, p. 803-818, https://doi.org/10.1111/j.1752-1688.2002.tb00998.x.","productDescription":"16 p.","startPage":"803","endPage":"818","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":236210,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"38","issue":"3","noUsgsAuthors":false,"publicationDate":"2007-06-08","publicationStatus":"PW","scienceBaseUri":"505a0bfbe4b0c8380cd5299c","contributors":{"authors":[{"text":"Clark, Gregory M. gmclark@usgs.gov","contributorId":1377,"corporation":false,"usgs":true,"family":"Clark","given":"Gregory","email":"gmclark@usgs.gov","middleInitial":"M.","affiliations":[{"id":343,"text":"Idaho Water Science Center","active":true,"usgs":true}],"preferred":true,"id":403839,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Broshears, Robert E.","contributorId":40675,"corporation":false,"usgs":true,"family":"Broshears","given":"Robert","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":403838,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hooper, Richard P.","contributorId":19144,"corporation":false,"usgs":true,"family":"Hooper","given":"Richard","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":403836,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Goolsby, Donald A.","contributorId":46083,"corporation":false,"usgs":true,"family":"Goolsby","given":"Donald","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":403837,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70025102,"text":"70025102 - 2002 - Groundwater recharge and agricultural contamination","interactions":[],"lastModifiedDate":"2017-06-02T13:28:53","indexId":"70025102","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"Groundwater recharge and agricultural contamination","docAbstract":"<p><span>Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water–rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO</span><sub>3</sub><sup>–</sup><span>, N</span><sub>2</sub><span>, Cl, SO</span><sub>4</sub><sup>2–</sup><span>, H</span><sup>+</sup><span>, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well as a wide variety of pesticides and other organic compounds. For reactive contaminants like NO</span><sub>3</sub><sup>–</sup><span>, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.</span></p>","language":"English","publisher":"Springer","doi":"10.1007/s10040-001-0183-3","issn":"14312174","usgsCitation":"Böhlke, J., 2002, Groundwater recharge and agricultural contamination: Hydrogeology Journal, v. 10, no. 1, p. 153-179, https://doi.org/10.1007/s10040-001-0183-3.","productDescription":"27 p.","startPage":"153","endPage":"179","numberOfPages":"27","costCenters":[],"links":[{"id":236172,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":209568,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10040-001-0183-3"}],"volume":"10","issue":"1","noUsgsAuthors":false,"publicationDate":"2002-01-22","publicationStatus":"PW","scienceBaseUri":"505a2dbde4b0c8380cd5bfe7","contributors":{"authors":[{"text":"Böhlke, J.K. 0000-0001-5693-6455","orcid":"https://orcid.org/0000-0001-5693-6455","contributorId":96696,"corporation":false,"usgs":true,"family":"Böhlke","given":"J.K.","affiliations":[],"preferred":false,"id":403828,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70025096,"text":"70025096 - 2002 - A modular approach to addressing model design, scale, and parameter estimation issues in distributed hydrological modelling","interactions":[],"lastModifiedDate":"2012-03-12T17:20:56","indexId":"70025096","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"A modular approach to addressing model design, scale, and parameter estimation issues in distributed hydrological modelling","docAbstract":"A modular approach to model design and construction provides a flexible framework in which to focus the multidisciplinary research and operational efforts needed to facilitate the development, selection, and application of the most robust distributed modelling methods. A variety of modular approaches have been developed, but with little consideration for compatibility among systems and concepts. Several systems are proprietary, limiting any user interaction. The US Geological Survey modular modelling system (MMS) is a modular modelling framework that uses an open source software approach to enable all members of the scientific community to address collaboratively the many complex issues associated with the design, development, and application of distributed hydrological and environmental models. Implementation of a common modular concept is not a trivial task. However, it brings the resources of a larger community to bear on the problems of distributed modelling, provides a framework in which to compare alternative modelling approaches objectively, and provides a means of sharing the latest modelling advances. The concepts and components of the MMS are described and an example application of the MMS, in a decision-support system context, is presented to demonstrate current system capabilities. Copyright ?? 2002 John Wiley and Sons, Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrological Processes","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1002/hyp.344","issn":"08856087","usgsCitation":"Leavesley, G., Markstrom, S., Restrepo, P.J., and Viger, R., 2002, A modular approach to addressing model design, scale, and parameter estimation issues in distributed hydrological modelling: Hydrological Processes, v. 16, no. 2, p. 173-187, https://doi.org/10.1002/hyp.344.","startPage":"173","endPage":"187","numberOfPages":"15","costCenters":[],"links":[{"id":209513,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/hyp.344"},{"id":236059,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"16","issue":"2","noUsgsAuthors":false,"publicationDate":"2002-01-22","publicationStatus":"PW","scienceBaseUri":"5059e486e4b0c8380cd466b9","contributors":{"authors":[{"text":"Leavesley, G.H.","contributorId":93895,"corporation":false,"usgs":true,"family":"Leavesley","given":"G.H.","email":"","affiliations":[],"preferred":false,"id":403810,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Markstrom, S.L.","contributorId":76807,"corporation":false,"usgs":true,"family":"Markstrom","given":"S.L.","email":"","affiliations":[],"preferred":false,"id":403808,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Restrepo, Pedro J.","contributorId":73263,"corporation":false,"usgs":true,"family":"Restrepo","given":"Pedro","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":403807,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Viger, Roland J. 0000-0003-2520-714X","orcid":"https://orcid.org/0000-0003-2520-714X","contributorId":80711,"corporation":false,"usgs":true,"family":"Viger","given":"Roland J.","affiliations":[],"preferred":false,"id":403809,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}}
,{"id":70025088,"text":"70025088 - 2002 - Interactions between groundwater and surface water: The state of the science","interactions":[],"lastModifiedDate":"2012-03-12T17:20:26","indexId":"70025088","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"Interactions between groundwater and surface water: The state of the science","docAbstract":"The interactions between groundwater and surface water are complex. To understand these interactions in relation to climate, landform, geology, and biotic factors, a sound hydrogeoecological framework is needed. All these aspects are synthesized and exemplified in this overview. In addition, the mechanisms of interactions between groundwater and surface water (GW-SW) as they affect recharge-discharge processes are comprehensively outlined, and the ecological significance and the human impacts of such interactions are emphasized. Surface-water and groundwater ecosystems are viewed as linked components of a hydrologic continuum leading to related sustainability issues. This overview concludes with a discussion of research needs and challenges facting this evolving field. The biogeochemical processes within the upper few centimeters of sediments beneath nearly all surface-water bodies (hyporheic zone) have a profound effect on the chemistry of the water interchange, and here is where most of the recent research has been focusing. However, to advance conceptual and other modeling of GW-SW systems, a broader perspective of such interactions across and between surface-water bodies is needed, including multidimensional analyses, interface hydraulic characterization and spatial variability, site-to-region regionalization approaches, as well as cross-disciplinary collaborations.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrogeology Journal","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10040-001-0170-8","issn":"14312174","usgsCitation":"Sophocleous, M., 2002, Interactions between groundwater and surface water: The state of the science: Hydrogeology Journal, v. 10, no. 1, p. 52-67, https://doi.org/10.1007/s10040-001-0170-8.","startPage":"52","endPage":"67","numberOfPages":"16","costCenters":[],"links":[{"id":209470,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10040-001-0170-8"},{"id":235948,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"1","noUsgsAuthors":false,"publicationDate":"2002-01-11","publicationStatus":"PW","scienceBaseUri":"505a3cc3e4b0c8380cd63007","contributors":{"authors":[{"text":"Sophocleous, M.","contributorId":13373,"corporation":false,"usgs":true,"family":"Sophocleous","given":"M.","email":"","affiliations":[],"preferred":false,"id":403765,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}}
,{"id":70025085,"text":"70025085 - 2002 - Resident fish assemblages in shallow shorelines of a Columbia River impoundment","interactions":[],"lastModifiedDate":"2016-04-26T15:07:10","indexId":"70025085","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2900,"text":"Northwest Science","onlineIssn":"2161-9859","printIssn":"0029-344X","active":true,"publicationSubtype":{"id":10}},"title":"Resident fish assemblages in shallow shorelines of a Columbia River impoundment","docAbstract":"<p>During May-September 1995, we replicated an earlier (1984-85) study of fishes in shoreline habitats of the John Day Reservoir, Columbia River, to investigate fish assemblage structure at several spatial and temporal scales. A total of 37,400 resident fishes representing 24 taxa was collected in 359 beach seine hauls. Fish catch composition during 1984 and 1985 was very similar, but was greatly different from catch in 1995. During 1984-1985, four native taxa (chiselmouth, northern pikeminnow, suckers, and sand rollers) constituted more than 90% of the combined main-channel catch, with introduced taxa comprising only 1.3% of the main-channel catch. In contrast, during 1995 only 37.7% of the main-channel catch comprised chiselmouth, northern pikeminnow, suckers, and sand rollers, while 33.9% were introduced taxa, primarily sunfishes and yellow perch. This shift in catch composition was greatest in the lower reservoir where the 1995 catch was 61% introduced taxa. Although changes in species composition of near-shore reservoir fish assemblages over the 10-yr period appeared to be substantial, we are unsure of annual variability since we have only one season of sampling for comparison with the earlier study. The differences we observed could be a long-term response to reservoir aging, a short-term reaction to annual differences in hydrologic and thermal regimes, or simply the naturally varying reproductive success of some species.</p>","language":"English","issn":"0029344X","usgsCitation":"Barfoot, C., Gadomski, D., and Petersen, J., 2002, Resident fish assemblages in shallow shorelines of a Columbia River impoundment: Northwest Science, v. 76, no. 2, p. 103-117.","productDescription":"15 p.","startPage":"103","endPage":"117","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":654,"text":"Western Fisheries Research Center","active":true,"usgs":true}],"links":[{"id":235915,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"76","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aa97ae4b0c8380cd85e08","contributors":{"authors":[{"text":"Barfoot, C.A.","contributorId":51490,"corporation":false,"usgs":true,"family":"Barfoot","given":"C.A.","email":"","affiliations":[],"preferred":false,"id":403760,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gadomski, D.M.","contributorId":37101,"corporation":false,"usgs":true,"family":"Gadomski","given":"D.M.","email":"","affiliations":[],"preferred":false,"id":403759,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Petersen, J.H.","contributorId":72154,"corporation":false,"usgs":true,"family":"Petersen","given":"J.H.","email":"","affiliations":[],"preferred":false,"id":403761,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}}
,{"id":70025073,"text":"70025073 - 2002 - Using groundwater levels to estimate recharge","interactions":[],"lastModifiedDate":"2020-09-25T17:53:14.003551","indexId":"70025073","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"Using groundwater levels to estimate recharge","docAbstract":"Accurate estimation of groundwater recharge is extremely important for proper management of groundwater systems. Many different approaches exist for estimating recharge. This paper presents a review of methods that are based on groundwater-level data. The water-table fluctuation method may be the most widely used technique for estimating recharge; it requires knowledge of specific yield and changes in water levels over time. Advantages of this approach include its simplicity and an insensitivity to the mechanism by which water moves through the unsaturated zone. Uncertainty in estimates generated by this method relate to the limited accuracy with which specific yield can be determined and to the extent to which assumptions inherent in the method are valid. Other methods that use water levels (mostly based on the Darcy equation) are also described. The theory underlying the methods is explained. Examples from the literature are used to illustrate applications of the different methods.","language":"English","publisher":"Springer","doi":"10.1007/s10040-001-0178-0","issn":"14312174","usgsCitation":"Healy, R.W., and Cook, P., 2002, Using groundwater levels to estimate recharge: Hydrogeology Journal, v. 10, no. 1, p. 91-109, https://doi.org/10.1007/s10040-001-0178-0.","productDescription":"19 p.","startPage":"91","endPage":"109","numberOfPages":"19","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":235761,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"1","noUsgsAuthors":false,"publicationDate":"2002-01-12","publicationStatus":"PW","scienceBaseUri":"505bc059e4b08c986b32a08d","contributors":{"authors":[{"text":"Healy, R. W.","contributorId":89872,"corporation":false,"usgs":true,"family":"Healy","given":"R.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":403704,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cook, P.G.","contributorId":103807,"corporation":false,"usgs":true,"family":"Cook","given":"P.G.","email":"","affiliations":[],"preferred":false,"id":403705,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}}
]}