Nutrient loading is a subtle, yet serious threat to the preservation of high diversity wetlands such as peatlands. Pathways of nutrient loading and impacts on plant diversity in a small peatland in New York State, USA were determined by collecting and analyzing a suite of hydrogeological, hydro-chemical, soil, and vegetation data. Piezometer clusters within an intensive network constituted hydro-chemical sampling points and focal points for randomly selected vegetation quadrats and soil-coring locations. Hydrogeological data and nutrient analyses showed that P and K loading occurred chiefly by means of overland flow from an adjacent farm field, whereas N loading occurred predominantly through ground-water flow from the farm field. Redundancy analysis and polynomial regression showed that nutrients, particularly total P in peat, total K in peat, extractable NH4-N, and NO3-N flux in ground water, were strongly negatively correlated with plant diversity measures at the site. No other environmental variables except vegetation measures associated with eutrophication demonstrated such a strong relationship with plant diversity. Nitrate loading over 4 mg m−2 day−1 was associated with low plant diversity, and Ca fluxes between 80 and 130 mg m−2 day−1 were associated with high plant diversity. Areas in the site with particularly low vascular plant and bryophyte species richness and Shannon-Wiener diversity (H′) occurred adjacent to the farm field and near a hillside spring. High H′ and species richness of vascular plants and bryophytes occurred in areas that were further removed from agriculture, contained no highly dominant vegetation, and were situated directly along the ground-water flow paths of springs. These areas were characterized by relatively constant water levels and consistent, yet moderate fluxes of base cations and nutrients. Overall, this study demonstrates that knowledge of site hydrogeology is crucial for determining potential pathways of nutrient loading and for developing relationships between nutrient inflows and wetland plant diversity.
","language":"English","publisher":"Springer Link","doi":"10.1672/0277-5212(2002)022[0263:PONLAI]2.0.CO;2","usgsCitation":"Drexler, J.Z., and Bedford, B.L., 2002, Pathways of nutrient loading and impacts on plant diversity in a New York peatland: Wetlands, v. 22, no. 2, p. 263-281, https://doi.org/10.1672/0277-5212(2002)022[0263:PONLAI]2.0.CO;2.","productDescription":"19 p.","startPage":"263","endPage":"281","numberOfPages":"19","costCenters":[],"links":[{"id":233164,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"New York","otherGeospatial":"McLean Preserve Fen","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -76.27017974853516,\n 42.53297077712674\n ],\n [\n -76.26331329345703,\n 42.53297077712674\n ],\n [\n -76.26331329345703,\n 42.537461198323754\n ],\n [\n -76.27017974853516,\n 42.537461198323754\n ],\n [\n -76.27017974853516,\n 42.53297077712674\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"22","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a75afe4b0c8380cd77ca2","contributors":{"authors":[{"text":"Drexler, Judith Z. 0000-0002-0127-3866 jdrexler@usgs.gov","orcid":"https://orcid.org/0000-0002-0127-3866","contributorId":167492,"corporation":false,"usgs":true,"family":"Drexler","given":"Judith","email":"jdrexler@usgs.gov","middleInitial":"Z.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true},{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":401894,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bedford, B. L.","contributorId":41996,"corporation":false,"usgs":false,"family":"Bedford","given":"B.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":401893,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024602,"text":"70024602 - 2002 - Comparing shear-wave velocity profiles inverted from multichannel surface wave with borehole measurements","interactions":[],"lastModifiedDate":"2012-03-12T17:20:07","indexId":"70024602","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3418,"text":"Soil Dynamics and Earthquake Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Comparing shear-wave velocity profiles inverted from multichannel surface wave with borehole measurements","docAbstract":"Recent field tests illustrate the accuracy and consistency of calculating near-surface shear (S)-wave velocities using multichannel analysis of surface waves (MASW). S-wave velocity profiles (S-wave velocity vs. depth) derived from MASW compared favorably to direct borehole measurements at sites in Kansas, British Columbia, and Wyoming. Effects of changing the total number of recording channels, sampling interval, source offset, and receiver spacing on the inverted S-wave velocity were studied at a test site in Lawrence, Kansas. On the average, the difference between MASW calculated Vs and borehole measured Vs in eight wells along the Fraser River in Vancouver, Canada was less than 15%. One of the eight wells was a blind test well with the calculated overall difference between MASW and borehole measurements less than 9%. No systematic differences were observed in derived Vs values from any of the eight test sites. Surface wave analysis performed on surface data from Wyoming provided S-wave velocities in near-surface materials. Velocity profiles from MASW were confirmed by measurements based on suspension log analysis. ?? 2002 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Soil Dynamics and Earthquake Engineering","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0267-7261(02)00008-8","issn":"02677261","usgsCitation":"Xia, J., Miller, R., Park, C., Hunter, J., Harris, J.B., and Ivanov, J., 2002, Comparing shear-wave velocity profiles inverted from multichannel surface wave with borehole measurements: Soil Dynamics and Earthquake Engineering, v. 22, no. 3, p. 181-190, https://doi.org/10.1016/S0267-7261(02)00008-8.","startPage":"181","endPage":"190","numberOfPages":"10","costCenters":[],"links":[{"id":207780,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0267-7261(02)00008-8"},{"id":232983,"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":"5059f839e4b0c8380cd4cf5e","contributors":{"authors":[{"text":"Xia, J.","contributorId":63513,"corporation":false,"usgs":true,"family":"Xia","given":"J.","email":"","affiliations":[],"preferred":false,"id":401861,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Miller, R. D.","contributorId":92693,"corporation":false,"usgs":true,"family":"Miller","given":"R. D.","affiliations":[],"preferred":false,"id":401863,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Park, C.B.","contributorId":21714,"corporation":false,"usgs":true,"family":"Park","given":"C.B.","email":"","affiliations":[],"preferred":false,"id":401860,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hunter, J. A.","contributorId":94067,"corporation":false,"usgs":true,"family":"Hunter","given":"J. A.","affiliations":[],"preferred":false,"id":401864,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Harris, J. B.","contributorId":80441,"corporation":false,"usgs":true,"family":"Harris","given":"J.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":401862,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Ivanov, J.","contributorId":107068,"corporation":false,"usgs":true,"family":"Ivanov","given":"J.","email":"","affiliations":[],"preferred":false,"id":401865,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70024583,"text":"70024583 - 2002 - Prediction of the fate of p,p'-DDE in sediment on the Palos Verdes shelf, California, USA","interactions":[],"lastModifiedDate":"2017-09-14T14:25:50","indexId":"70024583","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1333,"text":"Continental Shelf Research","active":true,"publicationSubtype":{"id":10}},"title":"Prediction of the fate of p,p'-DDE in sediment on the Palos Verdes shelf, California, USA","docAbstract":"Long-term (60-yr) predictions of vertical profiles of p,p???-DDE concentrations in contaminated bottom sediments on the Palos Verdes shelf were calculated for three locations along the 60-m isobath using a numerical solution of the one-dimensional advection-diffusion equation. The calculations incorporated the following processes: sediment deposition (or erosion), depth-dependent solid-phase biodiffusive mixing, in situ diagenetic transformation, and loss of p,p???-DDE across the sediment-water interface by two mechanisms (resuspension of sediments by wave action and subsequent loss of p,p???-DDE to the water column by desorption, and desorption from sediments to porewater and subsequent molecular diffusion to the water column). A combination of field measurements, laboratory analyses, and calculations with supporting models was used to set parameters for the model. The model explains significant features observed in measurements made every 2 years from 1981 to 1997 by the County Sanitation Districts of Los Angeles (LACSD). Analyses of available data suggest that two sites northwest of the Whites Point sewage outfalls will remain depositional, even as particulate supply from the sewage-treatment plant and nearby Portuguese Bend Landslide decreases. At these sites, model predictions for 1991-2050 indicate that most of the existing inventory of p,p???-DDE will remain buried and that surface concentrations will gradually decrease. Analyses of data southeast of the outfalls suggest that erosion is likely to occur somewhere on the southeast edge of the existing effluent-affected deposit, and model predictions for such a site showed that erosion and biodiffusion will reintroduce the p,p???-DDE to the upper layer of sediments, with subsequent increases in surface concentrations and loss to the overlying water column.","language":"English","publisher":"Elsevier","doi":"10.1016/S0278-4343(01)00118-2","issn":"02784343","usgsCitation":"Sherwood, C.R., Drake, D., Wiberg, P., and Wheatcroft, R.A., 2002, Prediction of the fate of p,p'-DDE in sediment on the Palos Verdes shelf, California, USA: Continental Shelf Research, v. 22, no. 6-7, p. 1025-1058, https://doi.org/10.1016/S0278-4343(01)00118-2.","productDescription":"34 p.","startPage":"1025","endPage":"1058","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":233269,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Palos Verdes shelf","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -118.46557617187499,\n 33.764307046898494\n ],\n [\n -118.48205566406251,\n 33.696922692957685\n ],\n [\n -118.46694946289064,\n 33.66149615643826\n ],\n [\n -118.45321655273438,\n 33.637489243170826\n ],\n [\n -118.40927124023438,\n 33.62948545097293\n ],\n [\n -118.38043212890625,\n 33.592887216626245\n ],\n [\n -118.30764770507811,\n 33.57687060377715\n ],\n [\n -118.28842163085938,\n 33.62605502663528\n ],\n [\n -118.25546264648438,\n 33.65349459599047\n ],\n [\n -118.28567504882812,\n 33.6912097228257\n ],\n [\n -118.32000732421875,\n 33.70263528325575\n ],\n [\n -118.36257934570312,\n 33.716343950060214\n ],\n [\n -118.42437744140625,\n 33.714059324224124\n ],\n [\n -118.46557617187499,\n 33.764307046898494\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"22","issue":"6-7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a81f6e4b0c8380cd7b81a","contributors":{"authors":[{"text":"Sherwood, C. R.","contributorId":48235,"corporation":false,"usgs":true,"family":"Sherwood","given":"C.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":401789,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Drake, D.E.","contributorId":48150,"corporation":false,"usgs":true,"family":"Drake","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":401788,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Wiberg, P.L.","contributorId":33827,"corporation":false,"usgs":true,"family":"Wiberg","given":"P.L.","email":"","affiliations":[],"preferred":false,"id":401787,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Wheatcroft, R. A.","contributorId":76503,"corporation":false,"usgs":false,"family":"Wheatcroft","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":401790,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024582,"text":"70024582 - 2002 - Spatial and temporal distribution of contaminated, effluent-affected sediment on the Palos Verdes margin, southern California","interactions":[],"lastModifiedDate":"2018-04-09T12:27:30","indexId":"70024582","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1333,"text":"Continental Shelf Research","active":true,"publicationSubtype":{"id":10}},"title":"Spatial and temporal distribution of contaminated, effluent-affected sediment on the Palos Verdes margin, southern California","docAbstract":"A sedimentary deposit on the continental margin near the Palos Verdes Peninsula, California is comprised of sewage effluent and geologic materials and is contaminated with metals, pesticides (including DDT and associated compounds), and PCBs. The deposit was mapped with subbottom acoustic profilers, and sediment cores were analyzed for geochemical and physical properties to determine the volume of the deposit and the distribution and mass of contaminants. Mapping showed that the deposit ranges up to 60-cm thick, has a total volume exceeding 9 million m3, and covers over 40 km2. Virtually the entire effluent-affected deposit is contaminated with DDT and PCBs. Nearly half of the area of the deposit lies on the continental slope, but 70-75% of the volume of the deposit and total mass of DDT reside on the continental shelf. Analysis of data collected biennially since 1981 by the Sanitation Districts of Los Angeles County show that the mass of DDT has apparently decreased at some stations but has remained essentially constant at others. Temporal changes m mass per unit area of DDT are not statistically significant (at the 90% confidence level) at the most contaminated locations over a 16-yr period. The results of this mapping effort were used as a basis for modeling efforts described elsewhere in this issue.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Continental Shelf Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0278-4343(01)00108-X","issn":"02784343","usgsCitation":"Lee, H., Sherwood, C.R., Drake, D., Edwards, B.D., Wong, F., and Hamer, M., 2002, Spatial and temporal distribution of contaminated, effluent-affected sediment on the Palos Verdes margin, southern California: Continental Shelf Research, v. 22, no. 6-7, p. 859-880, https://doi.org/10.1016/S0278-4343(01)00108-X.","productDescription":"22 p.","startPage":"859","endPage":"880","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":233268,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Palos Verdes Peninsula","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -118.6,\n 33.5\n ],\n [\n -118,\n 33.5\n ],\n [\n -118,\n 33.85\n ],\n [\n -118.6,\n 33.85\n ],\n [\n -118.6,\n 33.5\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"22","issue":"6-7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9435e4b08c986b31a927","contributors":{"authors":[{"text":"Lee, H.J.","contributorId":96693,"corporation":false,"usgs":true,"family":"Lee","given":"H.J.","email":"","affiliations":[],"preferred":false,"id":401786,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sherwood, C. R.","contributorId":48235,"corporation":false,"usgs":true,"family":"Sherwood","given":"C.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":401784,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Drake, D.E.","contributorId":48150,"corporation":false,"usgs":true,"family":"Drake","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":401783,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Edwards, B. D.","contributorId":27056,"corporation":false,"usgs":true,"family":"Edwards","given":"B.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":401782,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Wong, F.","contributorId":66451,"corporation":false,"usgs":true,"family":"Wong","given":"F.","affiliations":[],"preferred":false,"id":401785,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Hamer, M.","contributorId":24138,"corporation":false,"usgs":true,"family":"Hamer","given":"M.","email":"","affiliations":[],"preferred":false,"id":401781,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70024579,"text":"70024579 - 2002 - Estimation of shoreline position and change using airborne topographic lidar data","interactions":[],"lastModifiedDate":"2017-08-29T14:50:43","indexId":"70024579","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2220,"text":"Journal of Coastal Research","active":true,"publicationSubtype":{"id":10}},"title":"Estimation of shoreline position and change using airborne topographic lidar data","docAbstract":"A method has been developed for estimating shoreline position from airborne scanning laser data. This technique allows rapid estimation of objective, GPS-based shoreline positions over hundreds of kilometers of coast, essential for the assessment of large-scale coastal behavior. Shoreline position, defined as the cross-shore position of a vertical shoreline datum, is found by fitting a function to cross-shore profiles of laser altimetry data located in a vertical range around the datum and then evaluating the function at the specified datum. Error bars on horizontal position are directly calculated as the 95% confidence interval on the mean value based on the Student's t distribution of the errors of the regression. The technique was tested using lidar data collected with NASA's Airborne Topographic Mapper (ATM) in September 1997 on the Outer Banks of North Carolina. Estimated lidar-based shoreline position was compared to shoreline position as measured by a ground-based GPS vehicle survey system. The two methods agreed closely with a root mean square difference of 2.9 m. The mean 95% confidence interval for shoreline position was ?? 1.4 m. The technique has been applied to a study of shoreline change on Assateague Island, Maryland/Virginia, where three ATM data sets were used to assess the statistics of large-scale shoreline change caused by a major 'northeaster' winter storm. The accuracy of both the lidar system and the technique described provides measures of shoreline position and change that are ideal for studying storm-scale variability over large spatial scales.","language":"English","publisher":"Coastal Education and Research Foundation","issn":"07490208","usgsCitation":"Stockdon, H., Sallenger, A.H., List, J.H., and Holman, R., 2002, Estimation of shoreline position and change using airborne topographic lidar data: Journal of Coastal Research, v. 18, no. 3, p. 502-513.","productDescription":"12 p.","startPage":"502","endPage":"513","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":233231,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":345280,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://journals.fcla.edu/jcr/article/view/81307/78447"}],"country":"United States","state":"Maryland, North Carolina, Virginia","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -75.69580078125,\n 37.47485808497102\n ],\n [\n -74.92675781249999,\n 37.47485808497102\n ],\n [\n -74.92675781249999,\n 38.44498466889473\n ],\n [\n -75.69580078125,\n 38.44498466889473\n ],\n [\n -75.69580078125,\n 37.47485808497102\n ]\n ]\n ]\n }\n },\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -76.2890625,\n 34.97600151317588\n ],\n [\n -74.92675781249999,\n 34.97600151317588\n ],\n [\n -74.92675781249999,\n 36.58024660149866\n ],\n [\n -76.2890625,\n 36.58024660149866\n ],\n [\n -76.2890625,\n 34.97600151317588\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"18","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0baae4b0c8380cd5280f","contributors":{"authors":[{"text":"Stockdon, H.F. 0000-0003-0791-4676","orcid":"https://orcid.org/0000-0003-0791-4676","contributorId":55992,"corporation":false,"usgs":true,"family":"Stockdon","given":"H.F.","affiliations":[],"preferred":false,"id":401772,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sallenger, A. H. Jr.","contributorId":8818,"corporation":false,"usgs":true,"family":"Sallenger","given":"A.","suffix":"Jr.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":401771,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"List, J. H.","contributorId":70406,"corporation":false,"usgs":true,"family":"List","given":"J.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":401773,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Holman, R.A.","contributorId":73751,"corporation":false,"usgs":true,"family":"Holman","given":"R.A.","email":"","affiliations":[],"preferred":false,"id":401774,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024578,"text":"70024578 - 2002 - North Atlantic Deep Water export to the Southern Ocean over the past 14 Myr: Evidence from Nd and Pb isotopes in ferromanganese crusts","interactions":[],"lastModifiedDate":"2014-09-02T09:29:00","indexId":"70024578","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3002,"text":"Paleoceanography","active":true,"publicationSubtype":{"id":10}},"title":"North Atlantic Deep Water export to the Southern Ocean over the past 14 Myr: Evidence from Nd and Pb isotopes in ferromanganese crusts","docAbstract":"The intensity of North Atlantic Deep Water (NADW) production has been one of the most important parameters controlling the global thermohaline ocean circulation system and climate. Here we present a new approach to reconstruct the overall strength of NADW export from the North Atlantic to the Southern Ocean over the past 14 Myr applying the deep water Nd and Pb isotope composition as recorded by ferromanganese crusts and nodules. We present the first long-term Nd and Pb isotope time series for deep Southern Ocean water masses, which are compared with previously published time series for NADW from the NW Atlantic Ocean. These data suggest a continuous and strong export of NADW, or a precursor of it, into the Southern Ocean between 14 and 3 Ma. An increasing difference in Nd and Pb isotope compositions between the NW Atlantic and the Southern Ocean over the past 3 Myr gives evidence for a progressive overall reduction of NADW export since the onset of Northern Hemisphere glaciation (NHG). The Nd isotope data allow us to assess at least semiquantitatively that the amount of this reduction has been in the range between 14 and 37% depending on location.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Paleoceanography","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Wiley","doi":"10.1029/2000PA000606","issn":"08838305","usgsCitation":"Frank, M., Whiteley, N., Kasten, S., Hein, J., and O’Nions, K., 2002, North Atlantic Deep Water export to the Southern Ocean over the past 14 Myr: Evidence from Nd and Pb isotopes in ferromanganese crusts: Paleoceanography, v. 17, no. 2, p. 12-13, https://doi.org/10.1029/2000PA000606.","startPage":"12","endPage":"13","numberOfPages":"2","costCenters":[],"links":[{"id":478695,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000pa000606","text":"Publisher Index Page"},{"id":233230,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":293251,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2000PA000606"}],"volume":"17","issue":"2","noUsgsAuthors":false,"publicationDate":"2002-05-21","publicationStatus":"PW","scienceBaseUri":"505a67ece4b0c8380cd73521","contributors":{"authors":[{"text":"Frank, M.","contributorId":103396,"corporation":false,"usgs":true,"family":"Frank","given":"M.","email":"","affiliations":[],"preferred":false,"id":401770,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Whiteley, N.","contributorId":37924,"corporation":false,"usgs":true,"family":"Whiteley","given":"N.","email":"","affiliations":[],"preferred":false,"id":401767,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kasten, S.","contributorId":37506,"corporation":false,"usgs":true,"family":"Kasten","given":"S.","email":"","affiliations":[],"preferred":false,"id":401766,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hein, J.R. 0000-0002-5321-899X","orcid":"https://orcid.org/0000-0002-5321-899X","contributorId":61429,"corporation":false,"usgs":true,"family":"Hein","given":"J.R.","affiliations":[],"preferred":false,"id":401769,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"O’Nions, K.","contributorId":39165,"corporation":false,"usgs":true,"family":"O’Nions","given":"K.","email":"","affiliations":[],"preferred":false,"id":401768,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70024576,"text":"70024576 - 2002 - Delineation of faulting and basin geometry along a seismic reflection transect in urbanized San Bernardino Valley, California","interactions":[],"lastModifiedDate":"2012-03-12T17:20:06","indexId":"70024576","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"Delineation of faulting and basin geometry along a seismic reflection transect in urbanized San Bernardino Valley, California","docAbstract":"Fourteen kilometers of continuous, shallow seismic reflection data acquired through the urbanized San Bernardino Valley, California, have revealed numerous faults between the San Jacinto and San Andreas faults as well as a complex pattern of downdropped and uplifted blocks. These data also indicate that the Loma Linda fault continues northeastward at least 4.5 km beyond its last mapped location on the southern edge of the valley and to within at least 2 km of downtown San Bernardino. Previously undetected faults within the valley northeast of the San Jacinto fault are also imaged, including the inferred western extension of the Banning fault and several unnamed faults. The Rialto-Colton fault is interpreted southwest of the San Jacinto fault. The seismic data image the top of the crystalline basement complex across 70% of the profile length and show that the basement has an overall dip of roughly 10?? southwest between Perris Hill and the San Jacinto fault. Gravity and aeromagnetic data corroborate the interpreted location of the San Jacinto fault and better constrain the basin depth along the seismic profile to be as deep as 1.7 km. These data also corroborate other fault locations and the general dip of the basement surface. At least 1.2 km of apparent vertical displacement on the basement is observed across the San Jacinto fault at the profile location. The basin geometry delineated by these data was used to generate modeled ground motions that show peak horizontal amplifications of 2-3.5 above bedrock response in the 0.05- to 1.0-Hz frequency band, which is consistent with recorded earthquake data in the valley.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Bulletin of the Seismological Society of America","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1785/0120010222","issn":"00371106","usgsCitation":"Stephenson, W.J., Odum, J.K., Williams, R.A., and Anderson, M., 2002, Delineation of faulting and basin geometry along a seismic reflection transect in urbanized San Bernardino Valley, California: Bulletin of the Seismological Society of America, v. 92, no. 6, p. 2504-2520, https://doi.org/10.1785/0120010222.","startPage":"2504","endPage":"2520","numberOfPages":"17","costCenters":[],"links":[{"id":207908,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1785/0120010222"},{"id":233196,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"92","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fe69e4b0c8380cd4ed0a","contributors":{"authors":[{"text":"Stephenson, W. J.","contributorId":87982,"corporation":false,"usgs":true,"family":"Stephenson","given":"W.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":401759,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Odum, J. K.","contributorId":105705,"corporation":false,"usgs":true,"family":"Odum","given":"J.","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":401761,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Williams, R. A.","contributorId":82323,"corporation":false,"usgs":true,"family":"Williams","given":"R.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":401758,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Anderson, M.L.","contributorId":93138,"corporation":false,"usgs":true,"family":"Anderson","given":"M.L.","email":"","affiliations":[],"preferred":false,"id":401760,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024572,"text":"70024572 - 2002 - Geostatistical mapping of effluent-affected sediment distribution on the Palos Verdes shelf","interactions":[],"lastModifiedDate":"2012-03-12T17:20:06","indexId":"70024572","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1333,"text":"Continental Shelf Research","active":true,"publicationSubtype":{"id":10}},"title":"Geostatistical mapping of effluent-affected sediment distribution on the Palos Verdes shelf","docAbstract":"Geostatistical techniques were used to study the spatial continuity of the thickness of effluent-affected sediment in the offshore Palos Verdes Margin area. The thickness data were measured directly from cores and indirectly from high-frequency subbottom profiles collected over the Palos Verdes Margin. Strong spatial continuity of the sediment thickness data was identified, with a maximum range of correlation in excess of 1.4 km. The spatial correlation showed a marked anisotropy, and was more than twice as continuous in the alongshore direction as in the cross-shelf direction. Sequential indicator simulation employing models fit to the thickness data variograms was used to map the distribution of the sediment, and to quantify the uncertainty in those estimates. A strong correlation between sediment thickness data and measurements of the mass of the contaminant p,p???-DDE per unit area was identified. A calibration based on the bivariate distribution of the thickness and p,p???-DDE data was applied using Markov-Bayes indicator simulation to extend the geostatistical study and map the contamination levels in the sediment. Integrating the map grids produced by the geostatistical study of the two variables indicated that 7.8 million m3 of effluent-affected sediment exist in the map area, containing approximately 61-72 Mg (metric tons) of p,p???-DDE. Most of the contaminated sediment (about 85% of the sediment and 89% of the p,p???-DDE) occurs in water depths < 100 m. The geostatistical study also indicated that the samples available for mapping are well distributed and the uncertainty of the estimates of the thickness and contamination level of the sediments is lowest in areas where the contaminated sediment is most prevalent. ?? 2002 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Continental Shelf Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0278-4343(01)00109-1","issn":"02784343","usgsCitation":"Murray, C., Lee, H., and Hampton, M.A., 2002, Geostatistical mapping of effluent-affected sediment distribution on the Palos Verdes shelf: Continental Shelf Research, v. 22, no. 6-7, p. 881-897, https://doi.org/10.1016/S0278-4343(01)00109-1.","startPage":"881","endPage":"897","numberOfPages":"17","costCenters":[],"links":[{"id":207871,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0278-4343(01)00109-1"},{"id":233129,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"22","issue":"6-7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a28b1e4b0c8380cd5a314","contributors":{"authors":[{"text":"Murray, C.J.","contributorId":84120,"corporation":false,"usgs":true,"family":"Murray","given":"C.J.","email":"","affiliations":[],"preferred":false,"id":401747,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lee, H.J.","contributorId":96693,"corporation":false,"usgs":true,"family":"Lee","given":"H.J.","email":"","affiliations":[],"preferred":false,"id":401748,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hampton, M. A.","contributorId":103271,"corporation":false,"usgs":true,"family":"Hampton","given":"M.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":401749,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024570,"text":"70024570 - 2002 - Characteristics of sediment discharge in the subarctic Yukon River, Alaska","interactions":[],"lastModifiedDate":"2012-03-12T17:20:06","indexId":"70024570","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1198,"text":"Catena","active":true,"publicationSubtype":{"id":10}},"title":"Characteristics of sediment discharge in the subarctic Yukon River, Alaska","docAbstract":"The characteristics of sediment discharge in the Yukon River, Alaska were investigated by monitoring water discharge, water turbidity and water temperature. The river-transported sediment, 90 wt.% or more, consists of silt and clay (grain size ??? 62.5 ??m), which probably originated in the glacier-covered mountains mostly in the Alaska Range. For early June to late August 1999, we continuously measured water turbidity and temperature near the estuary and in the middle of Yukon River by using self-recording turbidimeters and temperature data loggers. The water turbidity (ppm) was converted to suspended sediment concentration (SSC; mg/l) of river water, using a relation between simultaneous turbidity and SSC at each of the two sites, and then, the suspended sediment discharge, approximately equal to water discharge times SSC, was numerically obtained every 1 or 2 h. It should be noted that the sediment discharge in the Yukon River is controlled by SSC rather than water discharge. As a result, a peak sediment discharge occurred in mid or late August by local sediment runoffs due to glacier-melt (or glacier-melt plus rainfall), while a peak water discharge was produced by snowmelt in late June or early July. Application of the \"extended Shields diagram\" indicates that almost all the river-transported sediments are under complete suspension. ?? 2002 Elsevier Science B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Catena","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0341-8162(02)00032-2","issn":"03418162","usgsCitation":"Chikita, K., Kemnitz, R., and Kumai, R., 2002, Characteristics of sediment discharge in the subarctic Yukon River, Alaska: Catena, v. 48, no. 4, p. 235-253, https://doi.org/10.1016/S0341-8162(02)00032-2.","startPage":"235","endPage":"253","numberOfPages":"19","costCenters":[],"links":[{"id":207869,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0341-8162(02)00032-2"},{"id":233127,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"48","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f49ee4b0c8380cd4be0c","contributors":{"authors":[{"text":"Chikita, K.A.","contributorId":65257,"corporation":false,"usgs":true,"family":"Chikita","given":"K.A.","email":"","affiliations":[],"preferred":false,"id":401744,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kemnitz, R.","contributorId":58813,"corporation":false,"usgs":true,"family":"Kemnitz","given":"R.","email":"","affiliations":[],"preferred":false,"id":401742,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kumai, R.","contributorId":63994,"corporation":false,"usgs":true,"family":"Kumai","given":"R.","email":"","affiliations":[],"preferred":false,"id":401743,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024559,"text":"70024559 - 2002 - System analysis to estimate subsurface flow: From global level to the State of Minnesota","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70024559","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1539,"text":"Environmental Geology","active":true,"publicationSubtype":{"id":10}},"title":"System analysis to estimate subsurface flow: From global level to the State of Minnesota","docAbstract":"Stream runoff data globally and in the state of Minnesota were used to estimate subsurface water flow. This system approach is based, in principal, on unity of groundwater and surface water systems, and it is in stark contrast to the traditional deterministic approach based on modeling. In coordination with methodology of system analysis, two levels of study were used to estimate subsurface flow. First, the global stream runoff data were assessed to estimate the temporal-spatial variability of surface water runoff. Factor analysis was used to study the temporal-spatial variability of global runoff for the period from 1918 to 1967. Results of these analysis demonstrate that the variability of global runoff could be represented by seven major components (factor scores) that could be grouped into seven distinct independent grouping from the total of 18 continental slopes on the Earth. Computed variance value in this analysis is 76% and supports such analysis. The global stream runoff for this period is stationary, and is more closely connected with the stream flow of Asia to the Pacific Ocean as well as with the stream runoff of North America towards the Arctic and Pacific Oceans. The second level examines the distribution of river runoff (annual and for February) for various landscapes and the hydrogeological conditions in the State of Minnesota (218,000 km2). The annual and minimal monthly rate of stream runoff for 115 gauging stations with a period of observation of 47 years (1935-1981) were used to characterize the spatio-temporal distribution of stream runoff in Minnesota. Results of this analysis demonstrate that the annual stream runoff rate changes from 6.3, towards 3.95, and then to 2.09 1 s-1 km-2 (the difference is significant based on Student's criteria). These values in Minnesota correspond to ecological provinces from a mixed forest province towards the broadleaf forest and to prairie province, respectively. The distribution of minimal monthly stream runoff rate (February runoff) is controlled by hydrogeological systems in Minnesota. The difference between the two hydrogeological regions, Precambrian crystalline basement and Paleozoic artesian basin of 0.83 and 2.09 1/s/km2, is statistically significant. Within these regions, the monthly minimal runoff (0.5 and 1.68, and 0.87 and 3.11 1 s-1 km-2 for February, respectively) is also distinctly different for delineated subregions, depending on whether or not the Quaternary cover is present. The spatio-temporal structure that emerges could thus be used to generate river runoff and subsurface flow maps at any scale - from the global level to local detail. Such analysis was carried out in Minnesota with the detailed mapping of the subsurface flow for the Twin Cities Metropolitan area.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s00254-001-0495-6","issn":"09430105","usgsCitation":"Shmagin, B., and Kanivetsky, R., 2002, System analysis to estimate subsurface flow: From global level to the State of Minnesota: Environmental Geology, v. 42, no. 2-3, p. 259-269, https://doi.org/10.1007/s00254-001-0495-6.","startPage":"259","endPage":"269","numberOfPages":"11","costCenters":[],"links":[{"id":207759,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s00254-001-0495-6"},{"id":232948,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"42","issue":"2-3","noUsgsAuthors":false,"publicationDate":"2002-03-01","publicationStatus":"PW","scienceBaseUri":"505ba365e4b08c986b31fcb1","contributors":{"authors":[{"text":"Shmagin, B.A.","contributorId":48736,"corporation":false,"usgs":true,"family":"Shmagin","given":"B.A.","affiliations":[],"preferred":false,"id":401710,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kanivetsky, R.","contributorId":33093,"corporation":false,"usgs":true,"family":"Kanivetsky","given":"R.","affiliations":[],"preferred":false,"id":401709,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024558,"text":"70024558 - 2002 - A conceptual model of the Mount Spurr magmatic system from seismic and geochemical observations of the 1992 Crater Peak eruption sequence","interactions":[],"lastModifiedDate":"2019-06-04T10:11:19","indexId":"70024558","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1109,"text":"Bulletin of Volcanology","active":true,"publicationSubtype":{"id":10}},"title":"A conceptual model of the Mount Spurr magmatic system from seismic and geochemical observations of the 1992 Crater Peak eruption sequence","docAbstract":"A conceptual model of the geometry and dynamics of the Mount Spurr magmatic system is developed using seismic, geochemical, and visual observations of the 1992 Crater Peak eruption sequence. The basis for this model is a new classification of all located seismic events and results from prior studies of seismology, geology, geochemistry, and geophysics of the Mount Spurr area. Significant seismic features of the 1992 eruption sequence include (1) a distinct swarm of volcano-tectonic (VT) earthquakes in August 1991 directly beneath the Crater Peak vent, (2) a caldera-wide increase in VT earthquakes, lasting 7 months, which preceded the 27 June eruption, (3) two shallow swarms of VT earthquakes that occurred on 5 June and 27 June, the latter immediately preceding the 27 June eruption, (4) a mix of VT, long-period (LP), and hybrid events at depths of 20-40 km, which began coincident with the onset of seismic unrest and reached a peak after eruptive activity ended, (5) a strong swarm of VT earthquakes that began as the 16-17 September eruption was ending, (6) a prominent swarm of VT earthquakes on 9-10 November at depths of 1 to 4 km beneath Crater Peak, and (7) a smaller swarm of VT earthquakes in late December 1992, which were located between 7 and 10 km depth. These seismic observations, combined with geological, geochemical, and geophysical data and observations, suggest a deep magmatic source zone for Crater Peak andesites at depths of 20-40 km, a smaller mid-crustal storage zone at about 10 km depth, and a conduit that extends to the surface. We infer that the magmas erupted in 1992 were generated at depths of 20-40 km and rose to the mid-crustal storage zone that fed all three 1992 eruptions. The 1992 eruption sequence may have terminated when additional magma solidified at shallow depths.
","language":"English","doi":"10.1007/s00445-002-0201-x","issn":"02588900","usgsCitation":"Power, J., Jolly, A., Nye, C., and Harbin, M., 2002, A conceptual model of the Mount Spurr magmatic system from seismic and geochemical observations of the 1992 Crater Peak eruption sequence: Bulletin of Volcanology, v. 64, no. 3-4, p. 206-218, https://doi.org/10.1007/s00445-002-0201-x.","productDescription":"13 p.","startPage":"206","endPage":"218","numberOfPages":"13","costCenters":[],"links":[{"id":232947,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"64","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e394e4b0c8380cd460e7","contributors":{"authors":[{"text":"Power, J.","contributorId":48699,"corporation":false,"usgs":true,"family":"Power","given":"J.","email":"","affiliations":[],"preferred":false,"id":401707,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Jolly, A.","contributorId":82498,"corporation":false,"usgs":true,"family":"Jolly","given":"A.","email":"","affiliations":[],"preferred":false,"id":401708,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nye, C.","contributorId":16198,"corporation":false,"usgs":true,"family":"Nye","given":"C.","email":"","affiliations":[],"preferred":false,"id":401706,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Harbin, M.","contributorId":14611,"corporation":false,"usgs":true,"family":"Harbin","given":"M.","email":"","affiliations":[],"preferred":false,"id":401705,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024556,"text":"70024556 - 2002 - Sediment transport on the Palos Verdes shelf over seasonal to decadal time scales","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70024556","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1333,"text":"Continental Shelf Research","active":true,"publicationSubtype":{"id":10}},"title":"Sediment transport on the Palos Verdes shelf over seasonal to decadal time scales","docAbstract":"We combine direct observations, longer-term wave data, and model calculations to characterize resuspension and transport of fine-grained, effluent-affected sediment on the Palos Verdes shelf. Near-bed waves, currents, and suspended sediment concentrations were monitored during the winter of 1992-93 with a bottom tripod and current-meter mooring at a 63-m-deep site. Wave conditions that winter were moderate (??? 2 year recurrence interval), and mean current was alongshelf to the northwest; currents were not significantly correlated with wave conditions. Seven wave events during the winter (December-March) produced near-bed wave orbital velocities at the study site in excess of 14 cm s-1, the observed threshold for significant resuspension. Three of these events occurred during the bottom tripod deployment and are characterized by the highest persistent suspended sediment concentrations in the tripod record. Suspended sediment flux was alongshelf to the northwest for 5 of the 6 wave events for which current data were available; one event occurred during low southeast currents. Measured suspended sediment concentration and grain size generally agree with values that were calculated using a shelf sediment transport model with no adjustment of parameters from values determined for two muddy sites on the northern California shelf. We extend our seasonal observations to a period of almost 2 decades by applying the observed thresholds for wave-driven resuspension to near-bed wave conditions calculated from NDBC Buoy 46025 surface wave data. An average of 10 resuspension events per year, with an average duration of 1.6 days, were identified at a water depth of 60 m; the number of events dropped to 3 per year at 90 m, beyond the shelf break. For the majority of these events, calculated net suspended sediment flux is toward the northwest (alongshelf) at an average rate of 140 kg m-1 h-1; about a third of the events have net southeastward flux at an average rate of 30 kg m-1 h-1. The calculated thickness of the resuspended surface layer of the bed was less than 1 cm for all events at 60 m. ?? 2002 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Continental Shelf Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0278-4343(01)00116-9","issn":"02784343","usgsCitation":"Wiberg, P., Drake, D., Harris, C.K., and Noble, M., 2002, Sediment transport on the Palos Verdes shelf over seasonal to decadal time scales: Continental Shelf Research, v. 22, no. 6-7, p. 987-1004, https://doi.org/10.1016/S0278-4343(01)00116-9.","startPage":"987","endPage":"1004","numberOfPages":"18","costCenters":[],"links":[{"id":207734,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0278-4343(01)00116-9"},{"id":232913,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"22","issue":"6-7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b89e6e4b08c986b316f22","contributors":{"authors":[{"text":"Wiberg, P.L.","contributorId":33827,"corporation":false,"usgs":true,"family":"Wiberg","given":"P.L.","email":"","affiliations":[],"preferred":false,"id":401696,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Drake, D.E.","contributorId":48150,"corporation":false,"usgs":true,"family":"Drake","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":401697,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Harris, C. K.","contributorId":80337,"corporation":false,"usgs":true,"family":"Harris","given":"C.","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":401698,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Noble, M.","contributorId":15340,"corporation":false,"usgs":true,"family":"Noble","given":"M.","email":"","affiliations":[],"preferred":false,"id":401695,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024555,"text":"70024555 - 2002 - The dynamics of subtidal poleward flows over a narrow continental shelf, Palos Verdes, CA","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70024555","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1333,"text":"Continental Shelf Research","active":true,"publicationSubtype":{"id":10}},"title":"The dynamics of subtidal poleward flows over a narrow continental shelf, Palos Verdes, CA","docAbstract":"The Palos Verdes peninsula is a short, very narrow (< 3 km) shelf in southern California that is bracketed by two large embayments. In May 1992, arrays of up to 4 moorings and 2 benthic tripods were deployed in a yearlong study of the circulation processes over this shelf and the adjacent slope. Wind stress, coastal sea level, atmospheric pressure and wave records were obtained from offshore sites and from coastal stations surrounding Palos Verdes. Bottom stress calculated for the mid-shelf sites using a boundary-layer model and data from the above instruments indicated the bottom drag coefficient over this shelf is about 0.003 Currents flow toward the northwest along the shelf and upper slope. Speeds are generally around 20-30 cm/s. There was no obvious seasonal structure in the flow. The first EOF for subtidal alongshelf current accounted for nearly 70% of the variance at sites on the shelf and upper slope. The dominant fluctuations had periods between 5 and 20 days, periods longer than seen in the regional wind stress field. Coastal sea level and the alongshore gradient in sea level had a similar concentration of energy in the 5-20 day frequency band. About 30% of the alongshelf flow was coherent with the alongshelf pressure gradient; currents flowed down the pressure gradient with minimal phase lag. Winds accounted for only 15-20% of the variance in subtidal currents, but the measured effect of wind stress was large. A 1 dyne/cm2 wind stress was associated with a 20-30 cm/s alongshore current. Both the regional wind stress and the alongshelf pressure gradients had spatial scales much larger than found on this small shelf. Subtidal flows forced by these regional fields were set up in the adjacent, much broader basins. The currents amplified as they moved onto the narrow shelf between the basins. Hence, local wind-driven currents had anomalously large amplitudes. The momentum equations for alongshelf wind or pressure gradients did not balance because some of the measured terms were associated with regional fields, others with local process. Our observations suggest that it is more difficult to determine which measured fields reflect the local processes in regions with rapidly changing topography. ?? 2002 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Continental Shelf Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0278-4343(01)00112-1","issn":"02784343","usgsCitation":"Noble, M., Ryan, H.F., and Wiberg, P., 2002, The dynamics of subtidal poleward flows over a narrow continental shelf, Palos Verdes, CA: Continental Shelf Research, v. 22, no. 6-7, p. 923-944, https://doi.org/10.1016/S0278-4343(01)00112-1.","startPage":"923","endPage":"944","numberOfPages":"22","costCenters":[],"links":[{"id":207712,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0278-4343(01)00112-1"},{"id":232877,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"22","issue":"6-7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baaebe4b08c986b322acb","contributors":{"authors":[{"text":"Noble, M.A.","contributorId":93513,"corporation":false,"usgs":true,"family":"Noble","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":401694,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ryan, H. F.","contributorId":18002,"corporation":false,"usgs":true,"family":"Ryan","given":"H.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":401692,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Wiberg, P.L.","contributorId":33827,"corporation":false,"usgs":true,"family":"Wiberg","given":"P.L.","email":"","affiliations":[],"preferred":false,"id":401693,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024552,"text":"70024552 - 2002 - Movement of water through the thick unsaturated zone underlying Oro Grande and Sheep Creek Washes in the western Mojave Desert, USA","interactions":[],"lastModifiedDate":"2018-09-19T08:36:41","indexId":"70024552","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":"Movement of water through the thick unsaturated zone underlying Oro Grande and Sheep Creek Washes in the western Mojave Desert, USA","docAbstract":"Previous studies indicate that a small quantity of recharge occurs from infiltration of streamflow in intermittent streams in the upper Mojave River basin, in the western Mojave Desert, near Victorville, California. Chloride, tritium, and stable isotope data collected in the unsaturated zone between 1994 and 1998 from boreholes drilled in Oro Grande and Sheep Creek Washes indicate that infiltration of streamflow occurs to depths below the root zone, and presumably to the water table, along much of Oro Grande Wash and near the mountain front along Sheep Creek Wash. Differences in infiltration at sites along each wash are the result of hydrologic variables such as proximity to the mountain front, quantity of streamflow, and texture of the subsurface deposits. Differences in infiltration between the washes are the result of large-scale geomorphic processes. For example, Oro Grande wash is incised into the Victorville fan and infiltration has occurred at approximately the same location over recent geologic time. In contrast, Sheep Creek Wash overlies an active alluvial fan and the stream channel can move across the fan surface through time. Infiltration does not occur to depths below the root zone at control sites outside of the washes.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrogeology Journal","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10040-002-0194-8","issn":"14312174","usgsCitation":"Izbicki, J., Radyk, J., and Michel, R.L., 2002, Movement of water through the thick unsaturated zone underlying Oro Grande and Sheep Creek Washes in the western Mojave Desert, USA: Hydrogeology Journal, v. 10, no. 3, p. 409-427, https://doi.org/10.1007/s10040-002-0194-8.","startPage":"409","endPage":"427","numberOfPages":"19","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":232843,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207685,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10040-002-0194-8"}],"volume":"10","issue":"3","noUsgsAuthors":false,"publicationDate":"2002-04-24","publicationStatus":"PW","scienceBaseUri":"505a5f27e4b0c8380cd70dd5","contributors":{"authors":[{"text":"Izbicki, J. A. 0000-0003-0816-4408","orcid":"https://orcid.org/0000-0003-0816-4408","contributorId":28244,"corporation":false,"usgs":true,"family":"Izbicki","given":"J. A.","affiliations":[],"preferred":false,"id":401686,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Radyk, J.","contributorId":63984,"corporation":false,"usgs":true,"family":"Radyk","given":"J.","email":"","affiliations":[],"preferred":false,"id":401687,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Michel, R. L.","contributorId":86375,"corporation":false,"usgs":true,"family":"Michel","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":401688,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024551,"text":"70024551 - 2002 - Provisioning rates and time budgets of adult and nestling Bald Eagles at Inland Wisconsin nests","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70024551","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2442,"text":"Journal of Raptor Research","active":true,"publicationSubtype":{"id":10}},"title":"Provisioning rates and time budgets of adult and nestling Bald Eagles at Inland Wisconsin nests","docAbstract":"We used a remote video recording system and direct observation to quantify provisioning rate and adult and nestling behavior at Bald Eagle (Haliaeetus leucocephalus) nests in north-central Wisconsin in 1992 (N = 5) and 1993 (N = 8). Eagles nesting in this region have a high reproductive rate (??? 1.3 young/occupied territory), and the number of occupied territories has expanded nearly three-fold since 1980. The season-long provisioning rate averaged 5.2 prey deliveries/nest/d and 3.0 prey deliveries/nestling/d, and did not vary by year or with nestling number or age. Fish (Osteichthyes) made up 97% of identified prey deliveries followed by reptiles (Reptilia) (1.5%), birds (Aves) (1.2%), and mammals (Mammalia) (0.6%). Nearly 85% of prey items were >15 cm and <45 cm and 13% were <15 cm in length. Adult attendance (time ??? adult was at the nest) at nestling age 2-4 wk was >90% of the day and was negatively correlated with nestling age. Time adults spent feeding nestlings was negatively correlated with nestling age. Nestlings stood or sat in the nest >30% of the day, began to feed themselves, and exhibited increased mobility in the nest at 6-8 wk. We identified three stages of the nestling period and several benchmarks that may be useful when scheduling data collection for comparison of Bald Eagle nesting behavior. Our results support the hypothesis that food was not limiting this breeding population of Bald Eagles. ?? 2002 The Raptor Research Foundation, Inc.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Raptor Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"08921016","usgsCitation":"Keith, W.D., Andersen, D., Dykstra, C.R., Meyer, M., and Karasov, W.H., 2002, Provisioning rates and time budgets of adult and nestling Bald Eagles at Inland Wisconsin nests: Journal of Raptor Research, v. 36, no. 2, p. 121-127.","startPage":"121","endPage":"127","numberOfPages":"7","costCenters":[],"links":[{"id":232805,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a8fb2e4b0c8380cd7f8ee","contributors":{"authors":[{"text":"Keith, Warnke D.","contributorId":95236,"corporation":false,"usgs":true,"family":"Keith","given":"Warnke","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":401685,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Andersen, D. E.","contributorId":27816,"corporation":false,"usgs":true,"family":"Andersen","given":"D. E.","affiliations":[],"preferred":false,"id":401683,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dykstra, Cheryl R.","contributorId":18142,"corporation":false,"usgs":false,"family":"Dykstra","given":"Cheryl","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":401681,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Meyer, M.W.","contributorId":38094,"corporation":false,"usgs":true,"family":"Meyer","given":"M.W.","email":"","affiliations":[],"preferred":false,"id":401684,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Karasov, W. H.","contributorId":25889,"corporation":false,"usgs":false,"family":"Karasov","given":"W.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":401682,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70024550,"text":"70024550 - 2002 - Global modeling of land water and energy balances. Part III: Interannual variability","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70024550","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2344,"text":"Journal of Hydrometeorology","active":true,"publicationSubtype":{"id":10}},"title":"Global modeling of land water and energy balances. Part III: Interannual variability","docAbstract":"The Land Dynamics (LaD) model is tested by comparison with observations of interannual variations in discharge from 44 large river basins for which relatively accurate time series of monthly precipitation (a primary model input) have recently been computed. When results are pooled across all basins, the model explains 67% of the interannual variance of annual runoff ratio anomalies (i.e., anomalies of annual discharge volume, normalized by long-term mean precipitation volume). The new estimates of basin precipitation appear to offer an improvement over those from a state-of-the-art analysis of global precipitation (the Climate Prediction Center Merged Analysis of Precipitation, CMAP), judging from comparisons of parallel model runs and of analyses of precipitation-discharge correlations. When the new precipitation estimates are used, the performance of the LaD model is comparable to, but not significantly better than, that of a simple, semiempirical water-balance relation that uses only annual totals of surface net radiation and precipitation. This implies that the LaD simulations of interannual runoff variability do not benefit substantially from information on geographical variability of land parameters or seasonal structure of interannual variability of precipitation. The aforementioned analyses necessitated the development of a method for downscaling of long-term monthly precipitation data to the relatively short timescales necessary for running the model. The method merges the long-term data with a reference dataset of 1-yr duration, having high temporal resolution. The success of the method, for the model and data considered here, was demonstrated in a series of model-model comparisons and in the comparisons of modeled and observed interannual variations of basin discharge.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrometeorology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1175/1525-7541(2002)003<0311:GMOLWA>2.0.CO;2","issn":"1525755X","usgsCitation":"Shmakin, A., Milly, P., and Dunne, K., 2002, Global modeling of land water and energy balances. Part III: Interannual variability: Journal of Hydrometeorology, v. 3, no. 3, p. 311-321, https://doi.org/10.1175/1525-7541(2002)003<0311:GMOLWA>2.0.CO;2.","startPage":"311","endPage":"321","numberOfPages":"11","costCenters":[],"links":[{"id":487456,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1175/1525-7541(2002)003<0311:gmolwa>2.0.co;2","text":"Publisher Index Page"},{"id":207665,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1175/1525-7541(2002)003<0311:GMOLWA>2.0.CO;2"},{"id":232804,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"3","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a294ee4b0c8380cd5a846","contributors":{"authors":[{"text":"Shmakin, A.B.","contributorId":46723,"corporation":false,"usgs":true,"family":"Shmakin","given":"A.B.","email":"","affiliations":[],"preferred":false,"id":401679,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Milly, P. C. D.","contributorId":100489,"corporation":false,"usgs":true,"family":"Milly","given":"P. C. D.","affiliations":[],"preferred":false,"id":401680,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dunne, K.A.","contributorId":18920,"corporation":false,"usgs":true,"family":"Dunne","given":"K.A.","email":"","affiliations":[],"preferred":false,"id":401678,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024546,"text":"70024546 - 2002 - Real-time water quality monitoring and regression analysis to estimate nutrient and bacteria concentrations in Kansas streams","interactions":[],"lastModifiedDate":"2012-03-12T17:20:05","indexId":"70024546","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Real-time water quality monitoring and regression analysis to estimate nutrient and bacteria concentrations in Kansas streams","docAbstract":"An innovative approach currently is underway in Kansas to estimate and monitoring constituent concentrations in streams. Continuous in-stream water-quality monitors are installed at selected U.S. Geological Survey stream-gaging stations to provide real-time measurement of specific conductance, pH, water temperature, dissolved oxygen, turbidity, and total chlorophyll. In addition, periodic water samples are collected manually and analyzed for nutrients, bacteria, and other constituents of concern. Regression equations then are developed from measurements made by the water-quality monitors and analytical results of manually collected samples. These regression equations are used to estimate nutrient, bacteria, and other constituent concentrations. Concentrations then are available to calculate loads and yields to further assess water quality in watersheds. The continuous and real-time nature of the data may be important when considering recreational use of a water body; developing and monitoring total maximum daily loads; adjusting water-treatment strategies; and determining high constituent concentrations in time to prevent adverse effects on fish or other aquatic life.","largerWorkTitle":"Water Science and Technology","language":"English","issn":"02731223","usgsCitation":"Christensen, V., Rasmussen, P., and Ziegler, A., 2002, Real-time water quality monitoring and regression analysis to estimate nutrient and bacteria concentrations in Kansas streams, in Water Science and Technology, v. 45, no. 9, p. 205-211.","startPage":"205","endPage":"211","numberOfPages":"7","costCenters":[],"links":[{"id":233304,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a95b1e4b0c8380cd81b9d","contributors":{"authors":[{"text":"Christensen, V.G.","contributorId":23583,"corporation":false,"usgs":true,"family":"Christensen","given":"V.G.","email":"","affiliations":[],"preferred":false,"id":401662,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rasmussen, P.P.","contributorId":6887,"corporation":false,"usgs":true,"family":"Rasmussen","given":"P.P.","email":"","affiliations":[],"preferred":false,"id":401661,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ziegler, A.C.","contributorId":74398,"corporation":false,"usgs":true,"family":"Ziegler","given":"A.C.","email":"","affiliations":[],"preferred":false,"id":401663,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024539,"text":"70024539 - 2002 - Nitrate in aquifers beneath agricultural systems","interactions":[],"lastModifiedDate":"2012-03-12T17:20:06","indexId":"70024539","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Nitrate in aquifers beneath agricultural systems","docAbstract":"Research from several regions of the world provides spatially anecdotal evidence to hypothesize which hydrologic and agricultural factors contribute to groundwater vulnerability to nitrate contamination. Analysis of nationally consistent measurements from the U.S. Geological Survey's NAWOA program confirms these hypotheses for a substantial range of agricultural systems. Shallow unconfined aquifers are most susceptible to nitrate contamination associated with agricultural systems. Alluvial and other unconsolidated aquifers are the most vulnerable and shallow carbonate aquifers provide a substantial but smaller contamination risk. Where any of these aquifers are overlain by permeable soils the risk of contamination is larger. Irrigated systems can compound this vulnerability by increasing leaching facilitated by additional recharge and additional nutrient applications. The agricultural system of corn, soybeans, and hogs produced significantly larger concentrations of groundwater nitrate than all other agricultural systems, although mean nitrate concentrations in counties with dairy, poultry, cattle and grains, and horticulture systems were similar. If trends in the relation between increased fertilizer use and groundwater nitrate in the United States are repeated in other regions of the world, Asia may experience increasing problems because of recent increases in fertilizer use. Groundwater monitoring in Western and Eastern Europe as well as Russia over the next decade may provide data to determine if the trend in increased nitrate contamination can be reversed. If the concentrated livestock trend in the United States is global, it may be accompanied by increasing nitrogen contamination in groundwater. Concentrated livestock provide both point sources in the confinement area and intense non-point sources as fields close to facilities are used for manure disposal. Regions where irrigated cropland is expanding, such as in Asia, may experience the greatest impact of this practice.","largerWorkTitle":"Water Science and Technology","language":"English","issn":"02731223","usgsCitation":"Burkart, M.R., and Stoner, J., 2002, Nitrate in aquifers beneath agricultural systems, in Water Science and Technology, v. 45, no. 9, p. 19-28.","startPage":"19","endPage":"28","numberOfPages":"10","costCenters":[],"links":[{"id":233160,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a66a1e4b0c8380cd72eb9","contributors":{"authors":[{"text":"Burkart, M. R.","contributorId":42190,"corporation":false,"usgs":true,"family":"Burkart","given":"M.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":401640,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stoner, J.D.","contributorId":58261,"corporation":false,"usgs":true,"family":"Stoner","given":"J.D.","email":"","affiliations":[],"preferred":false,"id":401641,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024535,"text":"70024535 - 2002 - Historical patterns of river stage and fish communities as criteria for operations of dams on the Illinois river","interactions":[],"lastModifiedDate":"2018-02-23T15:38:59","indexId":"70024535","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3301,"text":"River Research and Applications","active":true,"publicationSubtype":{"id":10}},"title":"Historical patterns of river stage and fish communities as criteria for operations of dams on the Illinois river","docAbstract":"The hydrologic regime of the Illinois River has been altered over the past 100 years. Locks and dams regulate water surface elevations and flow, enabling commercial navigation to continue year round. This study relates changes in water surface elevation to fish abundance in the river, and establishes target criteria for operating locks and dams. Using long-term records of daily river stage, we identified ecologically meaningful hydrological parameters for eight gage locations along the Illinois River. Inter-annual variability of a long-term fisheries dataset beginning in 1957 was related to variability in stage, flood and recession duration, frequency, timing, and rate of change of water levels. Reversals in water surface elevation, maximum stage levels, and length of the spring flood were the most important parameters influencing abundance of age-zero fishes in annual collections. Smallmouth buffalo (Ictiobus bubalus), black crappie (Pomoxis nigromaculatus), freshwater drum (Aplodinotus grunneins), and white bass (Morone chrysops) were most abundant in samples during years that approximated the natural water level regime. Of the 33 hydrologic parameters evaluated for the entire water year from an Illinois River gage site on La Grange Reach, all except average stage in January and Julian date (JD) of maximum stage had moderate or high hydrologic alteration based on the historical range of variation (RVA). The highest degree of hydrologic alteration was for minimum stage levels (1-day, 3-day, and 7-day), rate-of-rise, and rate-of-fall. Other parameters that have been severely altered were 30-day minimum stage, 90-day maximum stage, and the annual number of water level reversals. Operations of the La Grange and Peoria locks and dams could be modified so water level variability would approximate that of the late 1800s, when fish and wildlife resources were abundant. The water regime could be regulated to maintain navigation and improve conditions for native plants and animals without increasing flood damages.
","language":"English","publisher":"Wiley","doi":"10.1002/rra.630","usgsCitation":"Koel, T., and Sparks, R.E., 2002, Historical patterns of river stage and fish communities as criteria for operations of dams on the Illinois river: River Research and Applications, v. 18, no. 1, p. 3-19, https://doi.org/10.1002/rra.630.","productDescription":"17 p.","startPage":"3","endPage":"19","costCenters":[],"links":[{"id":233087,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Illinois River","volume":"18","issue":"1","noUsgsAuthors":false,"publicationDate":"2002-01-28","publicationStatus":"PW","scienceBaseUri":"505a3195e4b0c8380cd5e045","contributors":{"authors":[{"text":"Koel, Todd M.","contributorId":196920,"corporation":false,"usgs":false,"family":"Koel","given":"Todd M.","affiliations":[],"preferred":false,"id":401612,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sparks, Richard E.","contributorId":39091,"corporation":false,"usgs":false,"family":"Sparks","given":"Richard","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":401613,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024532,"text":"70024532 - 2002 - Variability of suspended-sediment concentration at tidal to annual time scales in San Francisco Bay, USA","interactions":[],"lastModifiedDate":"2018-09-26T11:08:16","indexId":"70024532","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Variability of suspended-sediment concentration at tidal to annual time scales in San Francisco Bay, USA","docAbstract":"Singular spectrum analysis for time series with missing data (SSAM) was used to reconstruct components of a 6-yr time series of suspended-sediment concentration (SSC) from San Francisco Bay. Data were collected every 15 min and the time series contained missing values that primarily were due to sensor fouling. SSAM was applied in a sequential manner to calculate reconstructed components with time scales of variability that ranged from tidal to annual. Physical processes that controlled SSC and their contribution to the total variance of SSC were (1) diurnal, semidiurnal, and other higher frequency tidal constituents (24%), (2) semimonthly tidal cycles (21%), (3) monthly tidal cycles (19%), (4) semiannual tidal cycles (12%), and (5) annual pulses of sediment caused by freshwater inflow, deposition, and subsequent wind-wave resuspension (13%). Of the total variance 89% was explained and subtidal variability (65%) was greater than tidal variability (24%). Processes at subtidal time scales accounted for more variance of SSC than processes at tidal time scales because sediment accumulated in the water column and the supply of easily erodible bed sediment increased during periods of increased subtidal energy. This large range of time scales that each contained significant variability of SSC and associated contaminants can confound design of sampling programs and interpretation of resulting data.
","largerWorkTitle":"Continental Shelf Research","language":"English","doi":"10.1016/S0278-4343(02)00042-0","issn":"02784343","usgsCitation":"Schoellhamer, D., 2002, Variability of suspended-sediment concentration at tidal to annual time scales in San Francisco Bay, USA, in Continental Shelf Research, v. 22, no. 11-13, p. 1857-1866, https://doi.org/10.1016/S0278-4343(02)00042-0.","startPage":"1857","endPage":"1866","numberOfPages":"10","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":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":233052,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207821,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0278-4343(02)00042-0"}],"volume":"22","issue":"11-13","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc13de4b08c986b32a4c8","contributors":{"authors":[{"text":"Schoellhamer, D. H. 0000-0001-9488-7340","orcid":"https://orcid.org/0000-0001-9488-7340","contributorId":85624,"corporation":false,"usgs":true,"family":"Schoellhamer","given":"D. H.","affiliations":[],"preferred":false,"id":401605,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70024531,"text":"70024531 - 2002 - Natural attenuation of chlorinated solvents at Area 6, Dover Air Force Base: Groundwater biogeochemistry","interactions":[],"lastModifiedDate":"2012-03-12T17:20:06","indexId":"70024531","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Natural attenuation of chlorinated solvents at Area 6, Dover Air Force Base: Groundwater biogeochemistry","docAbstract":"Monitored natural attenuation (MNA) has recently emerged as a viable groundwater remediation technology in the United States. Area 6 at Dover Air Force Base (Dover, DE) was chosen as a test site to examine the potential for MNA of tetrachloroethene (PCE) and trichloroethene (TCE) in groundwater and aquifer sediments. A \"lines of evidence\" approach was used to document the occurrence of natural attenuation. Chlorinated hydrocarbon and biogeochemical data were used to develop a site-specific conceptual model where both anaerobic and aerobic biological processes are responsible for the destruction of PCE, TCE, and daughter metabolites. An examination of groundwater biogeochemical data showed a region of depleted dissolved oxygen with elevated dissolved methane and hydrogen concentrations. Reductive dechlorination likely dominated in the anaerobic portion of the aquifer where PCE and TCE levels were observed to decrease with a simultaneous increase in cis-1,2-dichloroethene (cis-DCE), vinyl chloride (VC), ethene, and dissolved chloride. Near the anaerobic/aerobic interface, concentrations of cis-DCE and VC decreased to below detection limits, presumably due to aerobic biotransformation processes. Therefore, the contaminant and daughter product plumes present at the site appear to have been naturally attenuated by a combination of active anaerobic and aerobic biotransformation processes. ?? 2002 Elsevier Science B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0169-7722(01)00218-2","issn":"01697722","usgsCitation":"Witt, M., Klecka, G., Lutz, E., Ei, T., Grosso, N., and Chapelle, F.H., 2002, Natural attenuation of chlorinated solvents at Area 6, Dover Air Force Base: Groundwater biogeochemistry: Journal of Contaminant Hydrology, v. 57, no. 1-2, p. 61-80, https://doi.org/10.1016/S0169-7722(01)00218-2.","startPage":"61","endPage":"80","numberOfPages":"20","costCenters":[],"links":[{"id":207800,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0169-7722(01)00218-2"},{"id":233017,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"57","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a62dbe4b0c8380cd72158","contributors":{"authors":[{"text":"Witt, M.E.","contributorId":82895,"corporation":false,"usgs":true,"family":"Witt","given":"M.E.","email":"","affiliations":[],"preferred":false,"id":401603,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Klecka, G.M.","contributorId":17014,"corporation":false,"usgs":true,"family":"Klecka","given":"G.M.","email":"","affiliations":[],"preferred":false,"id":401600,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lutz, E.J.","contributorId":8260,"corporation":false,"usgs":true,"family":"Lutz","given":"E.J.","email":"","affiliations":[],"preferred":false,"id":401599,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Ei, T.A.","contributorId":71733,"corporation":false,"usgs":true,"family":"Ei","given":"T.A.","email":"","affiliations":[],"preferred":false,"id":401602,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Grosso, N.R.","contributorId":70153,"corporation":false,"usgs":true,"family":"Grosso","given":"N.R.","email":"","affiliations":[],"preferred":false,"id":401601,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Chapelle, F. H.","contributorId":101697,"corporation":false,"usgs":true,"family":"Chapelle","given":"F.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":401604,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70024530,"text":"70024530 - 2002 - Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition","interactions":[],"lastModifiedDate":"2017-01-18T15:49:52","indexId":"70024530","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":924,"text":"Atmospheric Environment","active":true,"publicationSubtype":{"id":10}},"title":"Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition","docAbstract":"Depth-integrated snowpack chemistry was measured just prior to maximum snowpack depth during the winters of 1992-1999 at 12 sites co-located with National Atmospheric Deposition Program/National Trend Network (NADP/NTN) sites in the central and southern Rocky Mountains, USA. Winter volume-weighted mean wet-deposition concentrations were calculated for the NADP/NTN sites, and the data were compared to snowpack concentrations using the paired t-test and the Wilcoxon signed-rank test. No statistically significant differences were indicated in concentrations of SO42- or NO3- (p>0.1). Small, but statistically significant differences (p???0.03) were indicated for all other solutes analyzed. Differences were largest for Ca2+ concentrations, which on average were 2.3??eql-1 (43%) higher in the snowpack than in winter NADP/NTN samples. Eolian carbonate dust appeared to influence snowpack chemistry through both wet and dry deposition, and the effect increased from north to south. Dry deposition of eolian carbonates was estimated to have neutralized an average of 6.9??eql-1 and a maximum of 12??eql-1 of snowpack acidity at the southernmost sites. The good agreement between snowpack and winter NADP/NTN SO42- and NO3- concentrations indicates that for those solutes the two data sets can be combined to increase data density in high-elevation areas, where few NADP/NTN sites exist. This combination of data sets will allow for better estimates of atmospheric deposition of SO42- and NO3- across the Rocky Mountain region.","language":"English","publisher":"Elsevier","doi":"10.1016/S1352-2310(02)00181-4","issn":"13522310","usgsCitation":"Clow, D.W., Ingersoll, G.P., Mast, M.A., Turk, J.T., and Campbell, D.H., 2002, Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition: Atmospheric Environment, v. 36, no. 14, p. 2337-2348, https://doi.org/10.1016/S1352-2310(02)00181-4.","productDescription":"12 p.","startPage":"2337","endPage":"2348","numberOfPages":"12","costCenters":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"links":[{"id":233016,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":207799,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S1352-2310(02)00181-4"}],"volume":"36","issue":"14","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f88fe4b0c8380cd4d1a7","contributors":{"authors":[{"text":"Clow, David W. 0000-0001-6183-4824 dwclow@usgs.gov","orcid":"https://orcid.org/0000-0001-6183-4824","contributorId":1671,"corporation":false,"usgs":true,"family":"Clow","given":"David","email":"dwclow@usgs.gov","middleInitial":"W.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":401594,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ingersoll, George P. gpingers@usgs.gov","contributorId":1469,"corporation":false,"usgs":true,"family":"Ingersoll","given":"George","email":"gpingers@usgs.gov","middleInitial":"P.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":401595,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mast, M. Alisa 0000-0001-6253-8162 mamast@usgs.gov","orcid":"https://orcid.org/0000-0001-6253-8162","contributorId":827,"corporation":false,"usgs":true,"family":"Mast","given":"M.","email":"mamast@usgs.gov","middleInitial":"Alisa","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":401597,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Turk, John T.","contributorId":53363,"corporation":false,"usgs":true,"family":"Turk","given":"John","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":401598,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Campbell, Donald H. dhcampbe@usgs.gov","contributorId":1670,"corporation":false,"usgs":true,"family":"Campbell","given":"Donald","email":"dhcampbe@usgs.gov","middleInitial":"H.","affiliations":[],"preferred":true,"id":401596,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70024527,"text":"70024527 - 2002 - Recovery of severely compacted soils in the Mojave Desert, California, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:20:12","indexId":"70024527","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":904,"text":"Arid Land Research and Management","active":true,"publicationSubtype":{"id":10}},"title":"Recovery of severely compacted soils in the Mojave Desert, California, USA","docAbstract":"Often as a result of large-scale military maneuvers in the past, many soils in the Mojave Desert are highly vulnerable to soil compaction, particularly when wet. Previous studies indicate that natural recovery of severely compacted desert soils is extremely slow, and some researchers have suggested that subsurface compaction may not recover. Poorly sorted soils, particularly those with a loamy sand texture, are most vulnerable to soil compaction, and these soils are the most common in alluvial fans of the Mojave Desert. Recovery of compacted soil is expected to vary as a function of precipitation amounts, wetting-and-drying cycles, freeze-thaw cycles, and bioturbation, particularly root growth. Compaction recovery, as estimated using penetration depth and bulk density, was measured at 19 sites with 32 site-time combinations, including the former World War II Army sites of Camps Ibis, Granite, Iron Mountain, Clipper, and Essex. Although compaction at these sites was caused by a wide variety of forces, ranging from human trampling to tank traffic, the data do not allow segregation of differences in recovery rates for different compaction forces. The recovery rate appears to be logarithmic, with the highest rate of change occurring in the first few decades following abandonment. Some higher-elevation sites have completely recovered from soil compaction after 70 years. Using a linear model of recovery, the full recovery time ranges from 92 to 100 years; using a logarithmic model, which asymptotically approaches full recovery, the time required for 85% recovery ranges from 105-124 years.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Arid Land Research and Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1080/153249802760284829","issn":"15324982","usgsCitation":"Webb, R.H., 2002, Recovery of severely compacted soils in the Mojave Desert, California, USA: Arid Land Research and Management, v. 16, no. 3, p. 291-305, https://doi.org/10.1080/153249802760284829.","startPage":"291","endPage":"305","numberOfPages":"15","costCenters":[],"links":[{"id":207757,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1080/153249802760284829"},{"id":232946,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"16","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"50e4a33de4b0e8fec6cdb7d6","contributors":{"authors":[{"text":"Webb, R. H.","contributorId":13648,"corporation":false,"usgs":true,"family":"Webb","given":"R.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":401583,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ]}