The Wyoming snow fence (shield) has been widely used with precipitation gauges for snowfall measurement at more than 25 locations in Alaska since the late 1970s. This gauge's measurements have been taken as the reference for correcting wind‐induced gauge undercatch of snowfall in Alaska. Recently, this fence (shield) was tested in the World Meteorological Organization Solid Precipitation Measurement Intercomparison Project at four locations in the United States of America and Canada for six winter seasons. At the Intercomparison sites an octagonal vertical Double Fence with a Russian Tretyakov gauge or a Universal Belfort recording gauge was installed and used as the Intercomparison Reference (DFIR) to provide true snowfall amounts for this Intercomparison experiment. The Intercomparison data collected were compiled at the four sites that represent a variety of climate, terrain, and exposure. On the basis of these data sets the performance of the Wyoming gauge system for snowfall observations was carefully evaluated against the DFIR and snow cover data. The results show that (1) the mean snow catch efficiency of the Wyoming gauge compared with the DFIR is about 80–90%, (2) there exists a close linear relation between the measurements of the two gauge systems and this relation may serve as a transfer function to adjust the Wyoming gauge records to obtain an estimate of the true snowfall amount, (3) catch efficiency of the Wyoming gauge does not change with wind speed and temperature, and (4) Wyoming gauge measurements are generally compatible to the snowpack water equivalent at selected locations in northern Alaska. These results are important to our effort of determining true snowfall amounts in the high latitudes, and they are also useful for regional hydrologic and climatic analyses.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000WR900158","usgsCitation":"Yang, D., Kane, D.L., Hinzman, L.D., Goodison, B.E., Metcalfe, J.R., Louie, P.Y., Leavesley, G.H., Emerson, D.G., and Hanson, C.L., 2000, An evaluation of the Wyoming Gauge System for snowfall measurement: Water Resources Research, v. 36, no. 9, p. 2665-2677, https://doi.org/10.1029/2000WR900158.","productDescription":"13 p.","startPage":"2665","endPage":"2677","costCenters":[{"id":478,"text":"North Dakota Water Science Center","active":true,"usgs":true},{"id":34685,"text":"Dakota Water Science Center","active":true,"usgs":true}],"links":[{"id":233790,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"9","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"5059ea54e4b0c8380cd487b3","contributors":{"authors":[{"text":"Yang, Daqing","contributorId":203286,"corporation":false,"usgs":false,"family":"Yang","given":"Daqing","email":"","affiliations":[],"preferred":false,"id":394995,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kane, Douglas L.","contributorId":112099,"corporation":false,"usgs":true,"family":"Kane","given":"Douglas","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":394990,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hinzman, Larry D.","contributorId":97133,"corporation":false,"usgs":true,"family":"Hinzman","given":"Larry","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":394997,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Goodison, Barry E.","contributorId":203293,"corporation":false,"usgs":false,"family":"Goodison","given":"Barry","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":394996,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Metcalfe, John R.","contributorId":203294,"corporation":false,"usgs":false,"family":"Metcalfe","given":"John","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":394991,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Louie, Paul Y.T.","contributorId":60419,"corporation":false,"usgs":false,"family":"Louie","given":"Paul","email":"","middleInitial":"Y.T.","affiliations":[],"preferred":false,"id":394993,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Leavesley, George H. george@usgs.gov","contributorId":1202,"corporation":false,"usgs":true,"family":"Leavesley","given":"George","email":"george@usgs.gov","middleInitial":"H.","affiliations":[],"preferred":true,"id":394998,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Emerson, Douglas G.","contributorId":40579,"corporation":false,"usgs":true,"family":"Emerson","given":"Douglas","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":394992,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Hanson, Clayton L.","contributorId":203290,"corporation":false,"usgs":false,"family":"Hanson","given":"Clayton","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":394994,"contributorType":{"id":1,"text":"Authors"},"rank":9}]}} ,{"id":70022731,"text":"70022731 - 2000 - Detection of persistent organic pollutants in the Mississippi Delta using semipermeable membrane devices","interactions":[],"lastModifiedDate":"2018-12-12T08:27:28","indexId":"70022731","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":5331,"text":"Science of Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Detection of persistent organic pollutants in the Mississippi Delta using semipermeable membrane devices","docAbstract":"From semipermeable membrane devices (SPMDs) placed in five Mississippi Delta streams in 1996 and 1997, the persistent organic pollutants (POPs) aldrin, chlordane, DCPA, DDT, dieldrin, endrin, heptachlor, mirex, nonachlor, and toxaphene were detected. In addition, the insecticides chlorpyriphos, endosulfan, and hexachlorocyclohexanes were detected. Two low-solubility herbicides not detected commonly in surface water, pendimethalin and trifluralin, were also detected.
Sulfonylurea (SU), imidazolinone (IMI), and sulfonamide (SA) herbicides are new classes of low-application-rate herbicides increasingly used by farmers. Some of these herbicides affect both weed and crop species at low dosages and must be carefully used. Less is known about the effect of these compounds on non-crop plant species, but a concentration of 100 ng/l in water has been proposed as the threshold for possible plant toxicity for most of these herbicides. Hence, analytical methods must be capable of detecting SUs, IMIs, and SAs at concentrations less than 100 ng/l in ambient water samples. The authors developed a two-cartridge, solid-phase extraction method for isolating 12 SU, 3 IMI, and 1 SA herbicides by using high-performance liquid chromatography/electrospray ionization-mass spectrometry (HPLC/ESI-MS) to identify and quantify these herbicides to 10 ng/l. This method was used to analyze 196 surface- and ground-water samples collected from May to August 1998 throughout the Midwestern United States, and more than 100 quality-assurance and quality-control samples. During the 16 weeks of the study, the HPLC/ESI-MS maintained excellent calibration linearity across the calibration range from 5 to 500 ng/l, with correlation coefficients of 0.9975 or greater. Continuing calibration verification standards at 100-ng/l concentration were analyzed throughout the study, and the average measured concentrations for individual herbicides ranged from 93 to 100 ng/l. Recovery of herbicides from 27 reagent-water samples spiked at 50 and 100 ng/l ranged from 39 to 92%, and averaged 73%. The standard deviation of recoveries ranged from 14 to 26%, and averaged 20%. This variability reflects multiple instruments, operators, and the use of automated and manual sample preparation. Spiked environmental water samples had similar recoveries, although for some herbicides, the sample matrix enhanced recoveries by as much as 200% greater than the spiked concentration. This matrix enhancement was sample- and compound-dependent. Concentrations of herbicides in unspiked duplicate environmental samples were typically within 25% of each other. The results demonstrate the usefulness of HPLC/ESI-MS for determining low-application-rate herbicides at ambient concentrations.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0048-9697(99)00537-9","issn":"00489697","usgsCitation":"Furlong, E., Burkhardt, M., Gates, P.M., Werner, S., and Battaglin, W., 2000, Routine determination of sulfonylurea, imidazolinone, and sulfonamide herbicides at nanogram-per-liter concentrations by solid-phase extraction and liquid chromatography/mass spectrometry: Science of Total Environment, v. 248, no. 2-3, p. 135-146, https://doi.org/10.1016/S0048-9697(99)00537-9.","productDescription":"12 p.","startPage":"135","endPage":"146","costCenters":[{"id":452,"text":"National Water Quality Laboratory","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233528,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208095,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0048-9697(99)00537-9"}],"volume":"248","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aaeace4b0c8380cd8716c","contributors":{"authors":[{"text":"Furlong, E. T. 0000-0002-7305-4603","orcid":"https://orcid.org/0000-0002-7305-4603","contributorId":98346,"corporation":false,"usgs":true,"family":"Furlong","given":"E. T.","affiliations":[],"preferred":false,"id":394691,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Burkhardt, M.R.","contributorId":70410,"corporation":false,"usgs":true,"family":"Burkhardt","given":"M.R.","email":"","affiliations":[],"preferred":false,"id":394689,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gates, Paul M.","contributorId":31411,"corporation":false,"usgs":true,"family":"Gates","given":"Paul","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":394688,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Werner, S.L.","contributorId":82734,"corporation":false,"usgs":true,"family":"Werner","given":"S.L.","email":"","affiliations":[],"preferred":false,"id":394690,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Battaglin, W.A.","contributorId":16376,"corporation":false,"usgs":true,"family":"Battaglin","given":"W.A.","email":"","affiliations":[],"preferred":false,"id":394687,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70022674,"text":"70022674 - 2000 - Microbial H2 cycling does not affect δ2H values of ground water","interactions":[],"lastModifiedDate":"2018-12-10T09:06:58","indexId":"70022674","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"Microbial H2 cycling does not affect δ2H values of ground water","docAbstract":"Stable hydrogen-isotope values of ground water (δ2H) and dissolved hydrogen concentrations (H(2(aq)) were quantified in a petroleum-hydrocarbon contaminated aquifer to determine whether the production/consumption of H2 by subsurface microorganisms affects ground water &delta2H values. The range of &delta2H observed in monitoring wells sampled (-27.8 ‰c to -15.5 ‰c) was best explained, however, by seasonal differences in recharge temperature as indicated using ground water δ18O values, rather than isotopic exchange reactions involving the microbial cycling of H2 during anaerobic petroleum-hydrocarbon biodegradation. The absence of a measurable hydrogen-isotope exchange between microbially cycled H2 and ground water reflects the fact that the amount of H2 available from the anaerobic decomposition of petroleum hydrocarbons is small relative to the amount of hydrogen present in water, even though milligram per liter concentrations of readily biodegradable contaminants are present at the study site. Additionally, isotopic fractionation calculations indicate that in order for H2 cycling processes to affect δ2H values of ground water, relatively high concentrations of H2 (>0.080 M) would have to be maintained, considerably higher than the 0.2 to 26 nM present at this site and characteristic of anaerobic conditions in general. These observations suggest that the conventional approach of using δ2H and δ18O values to determine recharge history is appropriate even for those ground water systems characterized by anaerobic conditions and extensive microbial H2 cycling.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2000.tb00223.x","issn":"0017467X","usgsCitation":"Landmeyer, J., Chapelle, F.H., and Bradley, P., 2000, Microbial H2 cycling does not affect δ2H values of ground water: Ground Water, v. 38, no. 3, p. 376-380, https://doi.org/10.1111/j.1745-6584.2000.tb00223.x.","productDescription":"5 p.","startPage":"376","endPage":"380","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233819,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":276302,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1745-6584.2000.tb00223.x"}],"volume":"38","issue":"3","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"505a563ee4b0c8380cd6d456","contributors":{"authors":[{"text":"Landmeyer, J. E.","contributorId":91140,"corporation":false,"usgs":true,"family":"Landmeyer","given":"J. E.","affiliations":[],"preferred":false,"id":394498,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chapelle, F. H.","contributorId":101697,"corporation":false,"usgs":true,"family":"Chapelle","given":"F.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":394499,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bradley, P. M. 0000-0001-7522-8606","orcid":"https://orcid.org/0000-0001-7522-8606","contributorId":29465,"corporation":false,"usgs":true,"family":"Bradley","given":"P. M.","affiliations":[],"preferred":false,"id":394497,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022673,"text":"70022673 - 2000 - Isotope hydrology dynamics of riverine wetlands in the Kankakee Watershed, Indiana","interactions":[],"lastModifiedDate":"2022-08-25T15:52:46.173875","indexId":"70022673","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Isotope hydrology dynamics of riverine wetlands in the Kankakee Watershed, Indiana","docAbstract":"Wetland restoration activities may disturb shallow ground-water flow dynamics. There may be unintentional sources of water flowing into a constructed wetland that could compromise the long-term viability of a wetland function. Measurement of naturally-occurring isotopes in the hydrosphere can provide an indication of provenance, flow paths or components, and residence times or ages of wetland ground-water flow systems. Hydraulic head measurements may not provide sufficient detail of shallow flow disturbances and can be complemented by analyzing isotopes in waters flowing through the wetland. Two north-central Indiana wetlands in the Kankakee watershed are being studied to determine the adequacy of wetland restoration activities. The native LaSalle wetland and the restored Hog Marsh wetland have contrasting ground-water flow regimes. The conservative water isotopes 18O, 2H, and 3H, and selected solute isotopes 13C, 14C, 15N, 34S, 87Sr, and 206–208Pb, demonstrate the complexity of ground-water flow in Hog Marsh compared to the established flow regime at the LaSalle wetland.
","language":"English","publisher":"American Water Resources Association","publisherLocation":"Herndon, VA, United States","doi":"10.1111/j.1752-1688.2000.tb04305.x","issn":"1093474X","usgsCitation":"Sidle, W., Arihood, L., and Bayless, R., 2000, Isotope hydrology dynamics of riverine wetlands in the Kankakee Watershed, Indiana: Journal of the American Water Resources Association, v. 36, no. 4, p. 771-790, https://doi.org/10.1111/j.1752-1688.2000.tb04305.x.","productDescription":"20 p.","startPage":"771","endPage":"790","costCenters":[],"links":[{"id":233780,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Indiana","otherGeospatial":"Hog Marsh Wetland, Kankakee Watershed, LaSalle Wetland","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -87.506103515625,\n 40.697299008636755\n ],\n [\n -86.099853515625,\n 40.697299008636755\n ],\n [\n -86.099853515625,\n 41.75492216766298\n ],\n [\n -87.506103515625,\n 41.75492216766298\n ],\n [\n -87.506103515625,\n 40.697299008636755\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"36","issue":"4","noUsgsAuthors":false,"publicationDate":"2007-06-08","publicationStatus":"PW","scienceBaseUri":"505a3f8ae4b0c8380cd645e7","contributors":{"authors":[{"text":"Sidle, W.C.","contributorId":93911,"corporation":false,"usgs":true,"family":"Sidle","given":"W.C.","email":"","affiliations":[],"preferred":false,"id":394496,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Arihood, L.","contributorId":69752,"corporation":false,"usgs":true,"family":"Arihood","given":"L.","affiliations":[],"preferred":false,"id":394495,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bayless, R.","contributorId":18146,"corporation":false,"usgs":true,"family":"Bayless","given":"R.","email":"","affiliations":[],"preferred":false,"id":394494,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022645,"text":"70022645 - 2000 - Effect of a constructed wetland on disinfection byproducts: Removal processes and production of precursors","interactions":[],"lastModifiedDate":"2018-12-03T10:44:06","indexId":"70022645","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Effect of a constructed wetland on disinfection byproducts: Removal processes and production of precursors","docAbstract":"The fate of halogenated disinfection byproducts (DBPs) in treatment wetlands and the changes in the DBP formation potential as wastewater treatment plant (WWTP)-derived water moves through the wetlands were investigated. Wetland inlet and outlet samples were analyzed for total organic halide (TOX), trihalomethanes (TH M), haloacetic acids (HAA), dissolved organic carbon (DOC), and UV absorbance. Removal of DBPs by the wetland ranged from 13 to 55% for TOX, from 78 to 97% for THM, and from 67 to 96% for HAA. The 24-h and 7-day nonpurgeable total organic halide (NPTOX), THM, and HAA formation potential yields were determined at the inlet and outlet of these wetlands. The effect of wetlands on the production of DBP precursors and their DBP-formation potential yield from wastewater was dramatic. The wetlands increased DBP yield up to a factor of almost 30. Specific changes in the DOC precursors were identified using 13C NMR spectroscopy.The fate of halogenated disinfection byproducts (DBPs) in treatment wetlands and the changes in the DBP formation potential as wastewater treatment plant (WWTP)-derived water moves through the wetlands were investigated. Wetland inlet and outlet samples were analyzed for total organic halide (TOX), trihalomethanes (THM), haloacetic acids (HAA), dissolved organic carbon (DOC), and UV absorbance. Removal of DBPs by the wetland ranged from 13 to 55% for TOX, from 78 to 97% for THM, and from 67 to 96% for HAA. The 24-h and 7-day nonpurgeable total organic halide (NPTOX), THM, and HAA formation potential yields were determined at the inlet and outlet of these wetlands. The effect of wetlands on the production of DBP precursors and their DBP-formation potential yield from wastewater was dramatic. The wetlands increased DBP yield up to a factor of almost 30. Specific changes in the DOC precursors were identified using 13C NMR spectroscopy.","language":"English","publisher":"ACS","doi":"10.1021/es9900407","issn":"0013936X","usgsCitation":"Rostad, C., Martin, B., Barber, L.B., Leenheer, J., and Daniel, S., 2000, Effect of a constructed wetland on disinfection byproducts: Removal processes and production of precursors: Environmental Science & Technology, v. 34, no. 13, p. 2703-2710, https://doi.org/10.1021/es9900407.","productDescription":"8 p.","startPage":"2703","endPage":"2710","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":233851,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208241,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es9900407"}],"volume":"34","issue":"13","noUsgsAuthors":false,"publicationDate":"2000-05-31","publicationStatus":"PW","scienceBaseUri":"505a05bae4b0c8380cd50f14","contributors":{"authors":[{"text":"Rostad, C.E.","contributorId":50939,"corporation":false,"usgs":true,"family":"Rostad","given":"C.E.","email":"","affiliations":[],"preferred":false,"id":394363,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Martin, Barbara S.","contributorId":30398,"corporation":false,"usgs":true,"family":"Martin","given":"Barbara S.","affiliations":[],"preferred":false,"id":394362,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Barber, L. B.","contributorId":64602,"corporation":false,"usgs":true,"family":"Barber","given":"L.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":394364,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Leenheer, J.A.","contributorId":75123,"corporation":false,"usgs":true,"family":"Leenheer","given":"J.A.","affiliations":[],"preferred":false,"id":394365,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Daniel, S.R.","contributorId":28379,"corporation":false,"usgs":true,"family":"Daniel","given":"S.R.","email":"","affiliations":[],"preferred":false,"id":394361,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70022623,"text":"70022623 - 2000 - A field technique for estimating aquifer parameters using flow log data","interactions":[],"lastModifiedDate":"2018-12-10T07:27:11","indexId":"70022623","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"A field technique for estimating aquifer parameters using flow log data","docAbstract":"A numerical model is used to predict flow along intervals between producing zones in open boreholes for comparison with measurements of borehole flow. The model gives flow under quasi-steady conditions as a function of the transmissivity and hydraulic head in an arbitrary number of zones communicating with each other along open boreholes. The theory shows that the amount of inflow to or outflow from the borehole under any one flow condition may not indicate relative zone transmissivity. A unique inversion for both hydraulic-head and transmissivity values is possible if flow is measured under two different conditions such as ambient and quasi-steady pumping, and if the difference in open-borehole water level between the two flow conditions is measured. The technique is shown to give useful estimates of water levels and transmissivities of two or more water-producing zones intersecting a single interval of open borehole under typical field conditions. Although the modeling technique involves some approximation, the principle limit on the accuracy of the method under field conditions is the measurement error in the flow log data. Flow measurements and pumping conditions are usually adjusted so that transmissivity estimates are most accurate for the most transmissive zones, and relative measurement error is proportionately larger for less transmissive zones. The most effective general application of the borehole-flow model results when the data are fit to models that systematically include more production zones of progressively smaller transmissivity values until model results show that all accuracy in the data set is exhausted.A numerical model is used to predict flow along intervals between producing zones in open boreholes for comparison with measurements of borehole flow. The model gives flow under quasi-steady conditions as a function of the transmissivity and hydraulic head in an arbitrary number of zones communicating with each other along open boreholes. The theory shows that the amount of inflow to or outflow from the borehole under any one flow condition may not indicate relative zone transmissivity. A unique inversion for both hydraulic-head and transmissivity values is possible if flow is measured under two different conditions such as ambient and quasi-steady pumping, and if the difference in open-borehole water level between the two flow conditions is measured. The technique is shown to give useful estimates of water levels and transmissivities of two or more water-producing zones intersecting a single interval of open borehole under typical field conditions. Although the modeling technique involves some approximation, the principle limit on the accuracy of the method under field conditions is the measurement error in the flow log data. Flow measurements and pumping conditions are usually adjusted so that transmissivity estimates are most accurate for the most transmissive zones, and relative measurement error is proportionately larger for less transmissive zones. The most effective general application of the borehole-flow model results when the data are fit to models that symmetrically include more production zones of progressively smaller transmissivity values until model results show that all accuracy in the data set is exhausted.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2000.tb00243.x","issn":"0017467X","usgsCitation":"Paillet, F.L., 2000, A field technique for estimating aquifer parameters using flow log data: Ground Water, v. 38, no. 4, p. 510-521, https://doi.org/10.1111/j.1745-6584.2000.tb00243.x.","productDescription":"12 p.","startPage":"510","endPage":"521","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230473,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"38","issue":"4","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"5059e3d6e4b0c8380cd4624d","contributors":{"authors":[{"text":"Paillet, Frederick L.","contributorId":63820,"corporation":false,"usgs":true,"family":"Paillet","given":"Frederick","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":394289,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022591,"text":"70022591 - 2000 - REE speciation in low-temperature acidic waters and the competitive effects of aluminum","interactions":[],"lastModifiedDate":"2018-12-12T08:45:04","indexId":"70022591","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1213,"text":"Chemical Geology","active":true,"publicationSubtype":{"id":10}},"title":"REE speciation in low-temperature acidic waters and the competitive effects of aluminum","docAbstract":"The effect of simultaneous competitive speciation of dissolved rare earth elements (REEs) in acidic waters (pH 3.3 to 5.2) has been evaluated by applying the PHREEQE code to the speciation of water analyses from Spain, Brazil, USA, and Canada. The main ions that might affect REE are Al3+, F-, SO42-, and PO43-. Fluoride, normally a significant complexer of REEs, is strongly associated with Al3+ in acid waters and consequently has little influence on REEs. The inclusion of aluminum concentrations in speciation calculations for acidic waters is essential for reliable speciation of REEs. Phosphate concentrations are too low (10-4 to 10-7 m) to affect REE speciation. Consequently, SO42- is the only important complexing ligand for REEs under these conditions. According to Millero [Millero, F.J., 1992. Stability constants for the formation of rare earth inorganic complexes as a function of ionic strength. Geochim. Cosmochim. Acta, 56, 3123-3132], the lanthanide sulfate stability constants are nearly constant with increasing atomic number so that no REE fractionation would be anticipated from aqueous complexation in acidic waters. Hence, REE enrichments or depletions must arise from mass transfer reactions.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0009-2541(99)00166-7","issn":"00092541","usgsCitation":"Gimeno, S.M., Auque, S.L., and Nordstrom, D.K., 2000, REE speciation in low-temperature acidic waters and the competitive effects of aluminum: Chemical Geology, v. 165, no. 3-4, p. 167-180, https://doi.org/10.1016/S0009-2541(99)00166-7.","productDescription":"14 p.","startPage":"167","endPage":"180","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230547,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206683,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0009-2541(99)00166-7"}],"volume":"165","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a9339e4b0c8380cd80cb1","contributors":{"authors":[{"text":"Gimeno, Serrano M.J.","contributorId":82182,"corporation":false,"usgs":true,"family":"Gimeno","given":"Serrano","email":"","middleInitial":"M.J.","affiliations":[],"preferred":false,"id":394178,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Auque, Sanz L.F.","contributorId":47245,"corporation":false,"usgs":true,"family":"Auque","given":"Sanz","email":"","middleInitial":"L.F.","affiliations":[],"preferred":false,"id":394177,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nordstrom, D. Kirk 0000-0003-3283-5136 dkn@usgs.gov","orcid":"https://orcid.org/0000-0003-3283-5136","contributorId":749,"corporation":false,"usgs":true,"family":"Nordstrom","given":"D.","email":"dkn@usgs.gov","middleInitial":"Kirk","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":false,"id":394179,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70022588,"text":"70022588 - 2000 - Dating young groundwater with sulfur hexafluoride: Natural and anthropogenic sources of sulfur hexafluoride","interactions":[],"lastModifiedDate":"2018-12-07T06:25:39","indexId":"70022588","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Dating young groundwater with sulfur hexafluoride: Natural and anthropogenic sources of sulfur hexafluoride","docAbstract":"Sulfur hexafluoride (SF6) is primarily of anthropogenic origin but also occurs naturally. The troposphere concentration of SF6 has increased from a steady state value of 0.054±0.009 to more than 4 parts per trillion volume during the past 40 years. An analytical procedure was developed for measuring concentrations of SF6 to less than 0.01 fmol/L in water. Groundwater can be dated with SF6 if it is in equilibrium with atmospheric SF6 at the time of recharge and does not contain significant SF6 from other sources. The dating range of SF6 is currently 0 to 30 years. The tracer was successfully used to date shallow groundwater of the Atlantic Coastal Plain sand aquifers of the United States and springs issuing near the top of the Blue Ridge Mountains of Virginia. Significant concentrations of naturally occurring SF6 were found in some igneous, volcanic, and sedimentary rocks and in some hydrothermal fluids.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000WR900151","usgsCitation":"Busenberg, E., and Plummer, N., 2000, Dating young groundwater with sulfur hexafluoride: Natural and anthropogenic sources of sulfur hexafluoride: Water Resources Research, v. 36, no. 10, p. 3011-3030, https://doi.org/10.1029/2000WR900151.","productDescription":"20 p.","startPage":"3011","endPage":"3030","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":487378,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000wr900151","text":"Publisher Index Page"},{"id":230471,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fde4e4b0c8380cd4e9d5","contributors":{"authors":[{"text":"Busenberg, Eurybiades ebusenbe@usgs.gov","contributorId":2271,"corporation":false,"usgs":true,"family":"Busenberg","given":"Eurybiades","email":"ebusenbe@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":394167,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Plummer, Niel 0000-0002-4020-1013 nplummer@usgs.gov","orcid":"https://orcid.org/0000-0002-4020-1013","contributorId":190100,"corporation":false,"usgs":true,"family":"Plummer","given":"Niel","email":"nplummer@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":394168,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70188322,"text":"70188322 - 2000 - Determining timescales for groundwater flow and solute transport","interactions":[],"lastModifiedDate":"2018-09-10T07:56:00","indexId":"70188322","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Determining timescales for groundwater flow and solute transport","docAbstract":"One of the principal uses of environmental tracers is for determining the ages of soil waters and groundwaters. (We may refer to this as ‘hydrochronology’by analogy with the dating of solid materials known as geochronology.) Information on soil water and groundwater age enables timescales for a range of subsurface processes to be determined. For example, ‘groundwater stratigraphy’is used increasingly to decipher past recharge rates and conditions in unconfined aquifers, in much the same way that sedimentary stratigraphy yields information about past depositional environments. The use of environmental tracers to determine water ages allows groundwater recharge rates and flow velocities to be determined independently, and commonly more accurately, than with traditional hydraulic methods where hydraulic properties of aquifers are poorly known or spatially variable. Studies of groundwater residence times in association with groundwater contamination studies can enable historic release rates of contaminants and contaminant transport rates to be determined. Where input rates are known, measurements of groundwater contaminant concentrations, together with groundwater dating, can sometimes be used for estimating chemical reaction rates. The combination of these dating methods with stable isotope measurements has sometimes allowed changes in contaminant sources over time to be determined.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Environmental tracers in subsurface hydrology","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Springer","publisherLocation":"Boston","doi":"10.1007/978-1-4615-4557-6_1","isbn":"978-1-4613-7057-4","usgsCitation":"Cook, P.G., and Bohlke, J., 2000, Determining timescales for groundwater flow and solute transport, chap. of Environmental tracers in subsurface hydrology, p. 1-30, https://doi.org/10.1007/978-1-4615-4557-6_1.","productDescription":"30 p.","startPage":"1","endPage":"30","costCenters":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":342145,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5937bf32e4b0f6c2d0d9c7c6","contributors":{"editors":[{"text":"Cook, Peter G.","contributorId":192638,"corporation":false,"usgs":false,"family":"Cook","given":"Peter","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":697213,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Herczeg, Andrew L.","contributorId":83007,"corporation":false,"usgs":true,"family":"Herczeg","given":"Andrew","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":697214,"contributorType":{"id":2,"text":"Editors"},"rank":2}],"authors":[{"text":"Cook, Peter G.","contributorId":192638,"corporation":false,"usgs":false,"family":"Cook","given":"Peter","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":697211,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bohlke, J.K. 0000-0001-5693-6455 jkbohlke@usgs.gov","orcid":"https://orcid.org/0000-0001-5693-6455","contributorId":191103,"corporation":false,"usgs":true,"family":"Bohlke","given":"J.K.","email":"jkbohlke@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true},{"id":36183,"text":"Hydro-Ecological Interactions Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":true,"id":697212,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022567,"text":"70022567 - 2000 - Determination of hydrologic pathways during snowmelt for alpine/subalpine basins, Rocky Mountain National Park, Colorado","interactions":[],"lastModifiedDate":"2018-04-02T16:52:49","indexId":"70022567","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Determination of hydrologic pathways during snowmelt for alpine/subalpine basins, Rocky Mountain National Park, Colorado","docAbstract":"Alpine/subalpine ecosystems in Rocky Mountain National Park may be sensitive to atmospherically derived acidic deposition. Two‐ and three‐component hydrograph separation analyses and correlation analyses were performed for six basins to provide insight into streamflow generation during snowmelt and to assess basin sensitivity to acidic deposition. Three‐component hydrograph separation results for five basins showed that streamflow contained from 42 to 57% direct snowmelt runoff, 37 to 54% subsurface water, and 4 to 13% direct rain runoff for the May through October 1994 study period. Subsurface contributions were 89% of total flow for the sixth basin. The reliability of hydrograph separation model assumptions was explored. Subsurface flow was positively correlated with the amount of surficial material in a basin and was negatively correlated with basin slope. Basins with extensive surficial material and shallow slopes are less susceptible to ecosystem changes due to acidic deposition than basins with less surficial material and steeper slopes. This study was initiated to expand the intensive hydrologic research that has been conducted in Loch Vale basin to a more regional scale.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1999WR900296","usgsCitation":"Suecker, J.K., Ryan, J.N., Kendall, C., and Jarrett, R.D., 2000, Determination of hydrologic pathways during snowmelt for alpine/subalpine basins, Rocky Mountain National Park, Colorado: Water Resources Research, v. 36, no. 1, p. 63-75, https://doi.org/10.1029/1999WR900296.","productDescription":"13 p.","startPage":"63","endPage":"75","costCenters":[],"links":[{"id":487328,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/1999wr900296","text":"Publisher Index Page"},{"id":230767,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ffabe4b0c8380cd4f30a","contributors":{"authors":[{"text":"Suecker, Julie K.","contributorId":124572,"corporation":false,"usgs":false,"family":"Suecker","given":"Julie","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":394102,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ryan, Joseph N.","contributorId":54290,"corporation":false,"usgs":false,"family":"Ryan","given":"Joseph","email":"","middleInitial":"N.","affiliations":[{"id":604,"text":"University of Colorado- Boulder","active":false,"usgs":true}],"preferred":false,"id":394103,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kendall, Carol 0000-0002-0247-3405 ckendall@usgs.gov","orcid":"https://orcid.org/0000-0002-0247-3405","contributorId":1462,"corporation":false,"usgs":true,"family":"Kendall","given":"Carol","email":"ckendall@usgs.gov","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":394100,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Jarrett, Robert D. rjarrett@usgs.gov","contributorId":2260,"corporation":false,"usgs":true,"family":"Jarrett","given":"Robert","email":"rjarrett@usgs.gov","middleInitial":"D.","affiliations":[],"preferred":true,"id":394101,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022332,"text":"70022332 - 2000 - Geochemical and microbiological methods for evaluating anaerobic processes in an aquifer contaminated by landfill leachate","interactions":[],"lastModifiedDate":"2018-12-10T08:22:49","indexId":"70022332","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Geochemical and microbiological methods for evaluating anaerobic processes in an aquifer contaminated by landfill leachate","docAbstract":"Extended tailing of tracer breakthrough is often observed in pulse injection tracer tests conducted in fractured geologic media. This behavior has been attributed to diffusive exchange of tracer between mobile fluids traveling through channels in fractures and relatively stagnant fluid between fluid channels, along fracture walls, or within the bulk matrix. We present a field example where tracer breakthrough tailing apparently results from nondiffusive transport. Tracer tests were conducted in a fractured crystalline rock using both a convergent and weak dipole injection and pumping scheme. Deuterated water, bromide, and pentafluorobenzoic acid were selected as tracers for their wide range in molecular diffusivity. The late time behavior of the normalized breakthrough curves were consistent for all tracers, even when the pumping rate was changed. The lack of separation between tracers of varying diffusivity indicates that strong breakthrough tailing in fractured geologic media may be caused by advective transport processes. This finding has implications for the interpretation of tracer tests designed to measure matrix diffusion in situ and the prediction of contaminant transport in fractured rock.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2000WR900080","usgsCitation":"Becker, M.W., and Shapiro, A.M., 2000, Tracer transport in fractured crystalline rock: Evidence of nondiffusive breakthrough tailing: Water Resources Research, v. 36, no. 7, p. 1677-1686, https://doi.org/10.1029/2000WR900080.","productDescription":"10 p.","startPage":"1677","endPage":"1686","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":479291,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2000wr900080","text":"Publisher Index Page"},{"id":230765,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb68ae4b08c986b326d17","contributors":{"authors":[{"text":"Becker, Matthew W.","contributorId":124569,"corporation":false,"usgs":false,"family":"Becker","given":"Matthew","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":394094,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shapiro, Allen M. 0000-0002-6425-9607 ashapiro@usgs.gov","orcid":"https://orcid.org/0000-0002-6425-9607","contributorId":2164,"corporation":false,"usgs":true,"family":"Shapiro","given":"Allen","email":"ashapiro@usgs.gov","middleInitial":"M.","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":394095,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022523,"text":"70022523 - 2000 - Negative pH and extremely acidic mine waters from Iron Mountain, California","interactions":[],"lastModifiedDate":"2018-12-07T05:58:04","indexId":"70022523","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Negative pH and extremely acidic mine waters from Iron Mountain, California","docAbstract":"Extremely acidic mine waters with pH values as low as -3.6, total dissolved metal concentrations as high as 200 g/L, and sulfate concentrations as high as 760 g/L, have been encountered underground in the Richmond Mine at Iron Mountain, CA. These are the most acidic waters known. The pH measurements were obtained by using the Pitzer method to define pH for calibration of glass membrane electrodes. The calibration of pH below 0.5 with glass membrane electrodes becomes strongly nonlinear but is reproducible to a pH as low as -4. Numerous efflorescent minerals were found forming from these acid waters. These extreme acid waters were formed primarily by pyrite oxidation and concentration by evaporation with minor effects from aqueous ferrous iron oxidation and efflorescent mineral formation.","language":"English","publisher":"ACS","doi":"10.1021/es990646v","issn":"0013936X","usgsCitation":"Nordstrom, D.K., Alpers, C.N., Ptacek, C., and Blowes, D., 2000, Negative pH and extremely acidic mine waters from Iron Mountain, California: Environmental Science & Technology, v. 34, no. 2, p. 254-258, https://doi.org/10.1021/es990646v.","productDescription":"5 p.","startPage":"254","endPage":"258","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230727,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206759,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es990646v"}],"volume":"34","issue":"2","noUsgsAuthors":false,"publicationDate":"1999-12-10","publicationStatus":"PW","scienceBaseUri":"505a643ae4b0c8380cd72942","contributors":{"authors":[{"text":"Nordstrom, D. Kirk 0000-0003-3283-5136 dkn@usgs.gov","orcid":"https://orcid.org/0000-0003-3283-5136","contributorId":749,"corporation":false,"usgs":true,"family":"Nordstrom","given":"D.","email":"dkn@usgs.gov","middleInitial":"Kirk","affiliations":[{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":false,"id":393939,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Alpers, Charles N. 0000-0001-6945-7365 cnalpers@usgs.gov","orcid":"https://orcid.org/0000-0001-6945-7365","contributorId":411,"corporation":false,"usgs":true,"family":"Alpers","given":"Charles","email":"cnalpers@usgs.gov","middleInitial":"N.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":393940,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ptacek, C.J.","contributorId":88616,"corporation":false,"usgs":true,"family":"Ptacek","given":"C.J.","affiliations":[],"preferred":false,"id":393938,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Blowes, D.W.","contributorId":21392,"corporation":false,"usgs":true,"family":"Blowes","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":393937,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022522,"text":"70022522 - 2000 - Debris flow monitoring in the Acquabona watershed on the Dolomites (Italian Alps)","interactions":[],"lastModifiedDate":"2022-08-16T18:05:08.732868","indexId":"70022522","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3068,"text":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","active":true,"publicationSubtype":{"id":10}},"title":"Debris flow monitoring in the Acquabona watershed on the Dolomites (Italian Alps)","docAbstract":"In 1997 a field monitoring system was installed in Acquabona Creek in the Dolomites (Eastern Italian Alps) to observe the hydrologic conditions for debris flow occurrence and some dynamic properties of debris flow. The monitoring system consists of three remote stations: an upper one located at the head of a deeply-incised channel and two others located downstream. The system is equipped with sensors for measuring rainfall, pore pressures in the mobile channel bottom, ground vibrations, debris flow depth, total normal stress and fluid pore-pressure at the base of the flow. Two video cameras record events at the upper channel station and one video is installed at the lowermost station. During summer 1998, three debris flows (volumes from less than 1000 m3 up to 9000 m3) occurred at Acquabona. The following results were obtained from a preliminary analysis of the data: 1) All of the flows were triggered by rainfalls of less than 1 hour duration, with peak rainfall intensities ranging from 4.8 to 14.7 mm / 10 minute. 2) Debris flows initiated in several reaches of the channel, including the head of the talus slope. 3) The initial surges of the mature flows had a higher solid concentration and a lower velocity (up to 4 m/s) than succeeding, more dilute surges (more than 7 m/s). 4) Total normal stress and pore fluid pressures measured at the base of the flow. (mean depth about 1.1 m) were similar (about 15 kPa), indicating a completely liquefied flow. 5) Peak flows entrained debris at a rate of about 6 m 3/m of channel length and channel bed scouring was proportional to the local slope gradient and was still evident in the lower channel where the slope was 7°.
","language":"English","publisher":"Elsevier","doi":"10.1016/S1464-1909(00)00090-3","issn":"14641909","usgsCitation":"Berti, M., Genevois, R., LaHusen, R., Simoni, A., and Tecca, P., 2000, Debris flow monitoring in the Acquabona watershed on the Dolomites (Italian Alps): Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere, v. 25, no. 9, p. 707-715, https://doi.org/10.1016/S1464-1909(00)00090-3.","productDescription":"9 p.","startPage":"707","endPage":"715","costCenters":[],"links":[{"id":230726,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Italy","otherGeospatial":"Acquabona Creek, Alps, Boite River, Dolomites","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n 12.126502990722656,\n 46.48231911886259\n ],\n [\n 12.214393615722654,\n 46.48231911886259\n ],\n [\n 12.214393615722654,\n 46.521784367720734\n ],\n [\n 12.126502990722656,\n 46.521784367720734\n ],\n [\n 12.126502990722656,\n 46.48231911886259\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"25","issue":"9","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fdf0e4b0c8380cd4ea0e","contributors":{"authors":[{"text":"Berti, M.","contributorId":22935,"corporation":false,"usgs":true,"family":"Berti","given":"M.","email":"","affiliations":[],"preferred":false,"id":393933,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Genevois, R.","contributorId":48728,"corporation":false,"usgs":true,"family":"Genevois","given":"R.","email":"","affiliations":[],"preferred":false,"id":393936,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"LaHusen, R.","contributorId":7446,"corporation":false,"usgs":true,"family":"LaHusen","given":"R.","email":"","affiliations":[],"preferred":false,"id":393932,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Simoni, A.","contributorId":25319,"corporation":false,"usgs":true,"family":"Simoni","given":"A.","email":"","affiliations":[],"preferred":false,"id":393935,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Tecca, P.R.","contributorId":24123,"corporation":false,"usgs":true,"family":"Tecca","given":"P.R.","email":"","affiliations":[],"preferred":false,"id":393934,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70022504,"text":"70022504 - 2000 - Calcite crystal growth inhibition by humic substances with emphasis on hydrophobic acids from the Florida Everglades","interactions":[],"lastModifiedDate":"2018-12-03T10:26:41","indexId":"70022504","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Calcite crystal growth inhibition by humic substances with emphasis on hydrophobic acids from the Florida Everglades","docAbstract":"The crystallization of calcium carbonate minerals plays an integral role in the water chemistry of terrestrial ecosystems. Humic substances, which are ubiquitous in natural waters, have been shown to reduce or inhibit calcite crystal growth in experiments. The purpose of this study is to quantify and understand the kinetic effects of hydrophobic organic acids isolated from the Florida Everglades and a fulvic acid from Lake Fryxell, Antarctica, on the crystal growth of calcite (CaCO3). Highly reproducible calcite growth experiments were performed in a sealed reactor at constant pH, temperature, supersaturation (Ω = 4.5), PCO2(10−3.5atm), and ionic strength (0.1 M) with various concentrations of organic acids. Higher plant-derived aquatic hydrophobic acids from the Everglades were more effective growth inhibitors than microbially derived fulvic acid from Lake Fryxell. Organic acid aromaticity correlated strongly with growth inhibition. Molecular weight and heteroatom content correlated well with growth inhibition, whereas carboxyl content and aliphatic nature did not.
Gram quantities of aquatic humic substances (AHS) were extracted from the Wakarusa River−Clinton Lake Reservoir system, near Lawrence, KS, to support nuclear magnetic resonance (NMR) experimental studies, report concentrations of dissolved organic carbon (DOC) and AHS, define sources of the AHS, and determine if the AHS yield sufficient quantities of haloacetic acids (HAA5) and trihalomethanes (THM4) that exceed U.S. Environmental Protection Agency (EPA) Maximum Contaminant Levels (MCL) in drinking water. AHS from the Wakarusa River and Clinton Lake originated from riparian forest vegetation, reflected respective effects of soil organic matter and aquatic algal/bacterial sources, and bore evidence of biological degradation and photodegradation. AHS from the Wakarusa River showed the effect of terrestrial sources, whereas Clinton Lake humic acid also reflected aquatic algal/bacterial sources. Greater amounts of carbon attributable to tannin-derived chemical structures may correspond with higher HAA5 and THM4 yields for Clinton Lake fulvic acid. Prior to appreciable leaf-fall from deciduous trees, the combined (humic and fulvic acid) THM4 formation potentials for the Wakarusa River approached the proposed EPA THM4 Stage I MCL of 80 μg/L, and the combined THM4 formation potential for Clinton Lake slightly exceeded the proposed THM4 Stage II MCL of 40 μg/L. Finally, AHS from Clinton Lake could account for most (>70%) of the THM4 concentrations in finished water from the Clinton Lake Water Treatment Plant based on September 23, 1996, THM4 results.
No abstract available.
","language":"English","publisher":"Wiley","doi":"10.1002/1099-1085(20001030)14:15<2797::AID-HYP402>3.0.CO;2-6","issn":"08856087","usgsCitation":"Bencala, K., 2000, Hyporheic zone hydrological processes: Hydrological Processes, v. 14, no. 15, p. 2797-2798, https://doi.org/10.1002/1099-1085(20001030)14:15<2797::AID-HYP402>3.0.CO;2-6.","productDescription":"2 p.","startPage":"2797","endPage":"2798","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230625,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"14","issue":"15","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a37bee4b0c8380cd61111","contributors":{"authors":[{"text":"Bencala, K.E.","contributorId":105312,"corporation":false,"usgs":true,"family":"Bencala","given":"K.E.","email":"","affiliations":[],"preferred":false,"id":392165,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022063,"text":"70022063 - 2000 - Hydrological responses to dynamically and statistically downscaled climate model output","interactions":[],"lastModifiedDate":"2012-03-12T17:19:44","indexId":"70022063","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1807,"text":"Geophysical Research Letters","active":true,"publicationSubtype":{"id":10}},"title":"Hydrological responses to dynamically and statistically downscaled climate model output","docAbstract":"Daily rainfall and surface temperature series were simulated for the Animas River basin, Colorado using dynamically and statistically downscaled output from the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) re-analysis. A distributed hydrological model was then applied to the downscaled data. Relative to raw NCEP output, downscaled climate variables provided more realistic stimulations of basin scale hydrology. However, the results highlight the sensitivity of modeled processes to the choice of downscaling technique, and point to the need for caution when interpreting future hydrological scenarios.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geophysical Research Letters","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/1999GL006078","issn":"00948276","usgsCitation":"Wilby, R., Hay, L., Gutowski, W., Arritt, R., Takle, E., Pan, Z., Leavesley, G., and Clark, M., 2000, Hydrological responses to dynamically and statistically downscaled climate model output: Geophysical Research Letters, v. 27, no. 8, p. 1199-1202, https://doi.org/10.1029/1999GL006078.","startPage":"1199","endPage":"1202","numberOfPages":"4","costCenters":[],"links":[{"id":489175,"rank":10000,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=1129&context=ge_at_pubs","text":"External Repository"},{"id":230850,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206812,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/1999GL006078"}],"volume":"27","issue":"8","noUsgsAuthors":false,"publicationDate":"2000-04-15","publicationStatus":"PW","scienceBaseUri":"505a36b0e4b0c8380cd6090b","contributors":{"authors":[{"text":"Wilby, R.L.","contributorId":96043,"corporation":false,"usgs":true,"family":"Wilby","given":"R.L.","email":"","affiliations":[],"preferred":false,"id":392229,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hay, L.E.","contributorId":54253,"corporation":false,"usgs":true,"family":"Hay","given":"L.E.","email":"","affiliations":[],"preferred":false,"id":392227,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gutowski, W.J. Jr.","contributorId":48344,"corporation":false,"usgs":true,"family":"Gutowski","given":"W.J.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":392225,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Arritt, R.W.","contributorId":39544,"corporation":false,"usgs":true,"family":"Arritt","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":392224,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Takle, E.S.","contributorId":7033,"corporation":false,"usgs":true,"family":"Takle","given":"E.S.","email":"","affiliations":[],"preferred":false,"id":392222,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Pan, Z.","contributorId":13006,"corporation":false,"usgs":true,"family":"Pan","given":"Z.","email":"","affiliations":[],"preferred":false,"id":392223,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Leavesley, G.H.","contributorId":93895,"corporation":false,"usgs":true,"family":"Leavesley","given":"G.H.","email":"","affiliations":[],"preferred":false,"id":392228,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Clark, M.P.","contributorId":49558,"corporation":false,"usgs":true,"family":"Clark","given":"M.P.","affiliations":[],"preferred":false,"id":392226,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70022068,"text":"70022068 - 2000 - Microbial degradation of chloroethenes in groundwater systems","interactions":[],"lastModifiedDate":"2021-04-06T14:55:25.903833","indexId":"70022068","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1923,"text":"Hydrogeology Journal","active":true,"publicationSubtype":{"id":10}},"title":"Microbial degradation of chloroethenes in groundwater systems","docAbstract":"The chloroethenes, tetrachloroethene (PCE) and trichloroethene (TCE) are among the most common contaminants detected in groundwater systems. As recently as 1980, the consensus was that chloroethene compounds were not significantly biodegradable in groundwater. Consequently, efforts to remediate chloroethene-contaminated groundwater were limited to largely unsuccessful pump-and-treat attempts. Subsequent investigation revealed that under reducing conditions, aquifer microorganisms can reductively dechlorinate PCE and TCE to the less chlorinated daughter products dichloroethene (DCE) and vinyl chloride (VC). Although recent laboratory studies conducted with halorespiring microorganisms suggest that complete reduction to ethene is possible, in the majority of groundwater systems reductive dechlorination apparently stops at DCE or VC. However, recent investigations conducted with aquifer and stream-bed sediments have demonstrated that microbial oxidation of these reduced daughter products can be significant under anaerobic redox conditions. The combination of reductive dechlorination of PCE and TCE under anaerobic conditions followed by anaerobic microbial oxidation of DCE and VC provides a possible microbial pathway for complete degradation of chloroethene contaminants in groundwater systems.
","language":"English","publisher":"Elsevier","doi":"10.1007/s100400050011","usgsCitation":"Bradley, P.M., 2000, Microbial degradation of chloroethenes in groundwater systems: Hydrogeology Journal, v. 8, no. 1, p. 104-111, https://doi.org/10.1007/s100400050011.","productDescription":"8 p.","startPage":"104","endPage":"111","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230279,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"8","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a564ae4b0c8380cd6d4b0","contributors":{"authors":[{"text":"Bradley, Paul M. 0000-0001-7522-8606 pbradley@usgs.gov","orcid":"https://orcid.org/0000-0001-7522-8606","contributorId":204639,"corporation":false,"usgs":true,"family":"Bradley","given":"Paul","email":"pbradley@usgs.gov","middleInitial":"M.","affiliations":[{"id":13634,"text":"South Atlantic Water Science Center","active":true,"usgs":true}],"preferred":true,"id":392241,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70022169,"text":"70022169 - 2000 - Fractionation of selenium isotopes during bacterial respiratory reduction of selenium oxyanions","interactions":[],"lastModifiedDate":"2018-12-12T08:49:02","indexId":"70022169","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Fractionation of selenium isotopes during bacterial respiratory reduction of selenium oxyanions","docAbstract":"Reduction of selenium oxyanions by microorganisms is an important process in the biogeochemical cycling of selenium. Numerous bacteria can reduce Se oxyanions, which are used as electron acceptors during the oxidation of organic matter in anoxic environments. In this study, we used a double spike (82Se and 74Se) thermal ionization mass spectrometry technique to quantify the isotopic fractionation achieved by three different species of anaerobic bacteria capable of accomplishing growth by respiratory reduction of selenate [SeO42− or Se(VI)] or selenite [SeO32− or Se(IV)] to Se(IV) or elemental selenium [Se(0)] coupled with the oxidation of lactate. Isotopic discrimination in these closed system experiments was evaluated by Rayleigh fractionation equations and numerical models. Growing cultures of Bacillus selenitireducens, a haloalkaliphile capable of growth using Se(IV) as an electron acceptor, induced a 80Se/76Se fractionation of −8.0 ± 0.4‰ (instantaneous ϵ value) during reduction of Se(IV) to Se(0). With Bacillus arsenicoselenatis, a haloalkaliphile capable of growth using Se(VI) as an electron acceptor, fractionations of −5.0 ± 0.5‰ and −6.0 ± 1.0‰ were observed for reduction of Se(VI) to Se(IV) and reduction of Se(IV) to Se(0), respectively. In growing cultures of Sulfurospirillum barnesii, a freshwater species capable of growth using Se(VI), fractionation was small initially, but near the end of the log growth phase, it increased to −4.0 ± 1.0‰ and −8.4 ± 0.4‰ for reduction of Se(VI) to Se(IV) and reduction of Se(IV) to Se(0), respectively. Washed cell suspensions of S. barnesii induced fractionations of −1.1 ± 0.4‰ during Se(VI) reduction, and −9.1 ± 0.5% for Se(IV) reduction, with some evidence for smaller values (e.g., −1.7‰) in the earliest-formed Se(0) results. These results demonstrate that dissimilatory reduction of selenate or selenite induces significant isotopic fractionation, and suggest that significant Se isotope ratio variation will be found in nature.
As part of the effort to restore the ∼10 000-km2 Everglades drainage in southern Florida, USA, we developed spatially explicit species index (SESI) models of a number of species and species groups. In this paper we describe the methodology and results of three such models: those for the Cape Sable Seaside Sparrow and the Snail Kite, and the species group model of long-legged wading birds. SESI models are designed to produce relative comparisons of one management alternative to a base scenario or to another alternative. The model outputs do not provide an exact quantitative prediction of future biotic group responses, but rather, when applying the same input data and different hydrologic plans, the models provide the best available means to compare the relative response of the biotic groups. We compared four alternative hydrologic management scenarios to a base scenario (i.e., predicted conditions assuming that current water management practices continue). We ranked the results of the comparisons for each set of models. No one scenario was beneficial to all species; however, they provide a uniform assessment, based on the best available observational information, of relative species responses to alternative water-management plans. As such, these models were used extensively in the restoration planning.
","language":"English","publisher":"Ecological Society of America","doi":"10.1890/1051-0761(2000)010[1849:LBSESI]2.0.CO;2","issn":"10510761","usgsCitation":"Curnutt, J.L., Comiskey, J., Nott, M., and Gross, L., 2000, Landscape-based spatially explicit species index models for everglades restoration: Ecological Applications, v. 10, no. 6, p. 1849-1860, https://doi.org/10.1890/1051-0761(2000)010[1849:LBSESI]2.0.CO;2.","productDescription":"12 p.","startPage":"1849","endPage":"1860","costCenters":[],"links":[{"id":230666,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Big Cypress National Preserve, Everglades National Park","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -81.38534545898438,\n 26.257704515406648\n ],\n [\n -81.38259887695312,\n 26.236765673594668\n ],\n [\n -81.43341064453125,\n 26.237997474610452\n ],\n [\n -81.43203735351562,\n 26.2145910237943\n ],\n [\n -81.55288696289062,\n 26.204734267107604\n ],\n [\n -81.61056518554688,\n 26.199805575765804\n ],\n [\n -81.72317504882812,\n 26.168996529230178\n ],\n [\n -81.72317504882812,\n 25.888878582127084\n ],\n [\n -81.67373657226562,\n 25.830797170738858\n ],\n [\n -81.64764404296875,\n 25.88393659458397\n ],\n [\n -81.48422241210938,\n 25.80112757645447\n ],\n [\n -81.3702392578125,\n 25.697225529877763\n ],\n [\n -81.27273559570311,\n 25.62914524992192\n ],\n [\n -81.221923828125,\n 25.507742380531404\n ],\n [\n -81.15600585937499,\n 25.37256835379414\n ],\n [\n -81.18621826171875,\n 25.224820176765036\n ],\n [\n -81.15188598632812,\n 25.152743274854956\n ],\n [\n -81.09695434570312,\n 25.10798445491342\n ],\n [\n -80.71792602539062,\n 25.111714982906328\n ],\n [\n -80.48721313476562,\n 25.191272441616\n ],\n [\n -80.43777465820312,\n 25.25960064916269\n ],\n [\n -80.44464111328125,\n 25.29437116258816\n ],\n [\n -80.57098388671874,\n 25.2918878849706\n ],\n [\n -80.56549072265625,\n 25.41722976060518\n ],\n [\n -80.54489135742188,\n 25.575891798572776\n ],\n [\n -80.4803466796875,\n 25.667522551344298\n ],\n [\n -80.48446655273438,\n 25.890114046690094\n ],\n [\n -80.43090820312499,\n 25.94816628853973\n ],\n [\n -80.43365478515625,\n 26.10612083235552\n ],\n [\n -80.44326782226562,\n 26.145576207592274\n ],\n [\n -80.34576416015625,\n 26.12091815959972\n ],\n [\n -80.34439086914062,\n 26.144343428856374\n ],\n [\n -80.29220581054688,\n 26.1899475672235\n ],\n [\n -80.28945922851562,\n 26.351267272877074\n ],\n [\n -80.24139404296875,\n 26.341422119377988\n ],\n [\n -80.20156860351562,\n 26.48532391504829\n ],\n [\n -80.20706176757812,\n 26.518506504902675\n ],\n [\n -80.23040771484375,\n 26.583614813585854\n ],\n [\n -80.29632568359375,\n 26.686729520004036\n ],\n [\n -80.44876098632812,\n 26.681821407205977\n ],\n [\n -80.46798706054688,\n 26.517277690994334\n ],\n [\n -80.49819946289062,\n 26.39925039312297\n ],\n [\n -80.58609008789062,\n 26.395560091430248\n ],\n [\n -80.65750122070312,\n 26.493927728762568\n ],\n [\n -80.80581665039062,\n 26.496385842983383\n ],\n [\n -80.8538818359375,\n 26.480407161007275\n ],\n [\n -80.958251953125,\n 26.466885003671486\n ],\n [\n -80.98434448242186,\n 26.436146919246013\n ],\n [\n -80.9857177734375,\n 26.261399213411483\n ],\n [\n -81.38534545898438,\n 26.257704515406648\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"10","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a441fe4b0c8380cd6689d","contributors":{"authors":[{"text":"Curnutt, J. L.","contributorId":97845,"corporation":false,"usgs":false,"family":"Curnutt","given":"J.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":392615,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Comiskey, J.","contributorId":54758,"corporation":false,"usgs":true,"family":"Comiskey","given":"J.","email":"","affiliations":[],"preferred":false,"id":392612,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nott, M.P.","contributorId":78677,"corporation":false,"usgs":true,"family":"Nott","given":"M.P.","email":"","affiliations":[],"preferred":false,"id":392614,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gross, L.J.","contributorId":65030,"corporation":false,"usgs":true,"family":"Gross","given":"L.J.","email":"","affiliations":[],"preferred":false,"id":392613,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70022202,"text":"70022202 - 2000 - Differences in topographic characteristics computed from 100- and 1000-m resolution digital elevation model data","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022202","displayToPublicDate":"2000-01-01T00:00:00","publicationYear":"2000","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"Differences in topographic characteristics computed from 100- and 1000-m resolution digital elevation model data","docAbstract":"Topographic characteristics computed from 100- and 1000-m resolution digital elevation model (DEM) data are compared for 50 locations representing varied terrain in the conterminous USA. The topographic characteristics are three parameters used extensively in hydrological research and modelling - slope (S), specific catchment area (A(s)) and a wetness index computed as the logarithm of the specific catchment area divided by slope [ln(A(s)/S)]. Slope values computed from 1000-m DEMs are smaller than those computed from 100-m DEMs; specific catchment area and the wetness index are larger for the 1000-m DEMs compared with the 100-m DEMs. Most of the differences between the 100- and 1000-m resolution DEMs can be attributed to terrain-discretization effects in the computation of the topographic characteristics and are not the result of smoothing or loss of terrain detail in the coarse data. In general, the terrain-discretization effects are greatest on flat terrain with long length-scale features, and the smoothing effects are greatest on steep terrain with short length-scale features. For the most part, the differences in the average values of the topographic characteristics computed from 100- and 1000-m resolution DEMs are predictable; that is, biases in the mean values for the characteristics computed from a 1000-m DEM can be corrected with simple linear equations. Copyright (C) 2000 John Wiley and Sons, Ltd.Topographic characteristics computed from 100- and 1000-m resolution digital elevation model (DEM) data are compared for 50 locations representing varied terrain in the conterminous USA. The topographic characteristics are three parameters used extensively in hydrological research and modelling - slope (S), specific catchment area (As) and a wetness index computed as the logarithm of the specific catchment area divided by slope [In(As/S)]. Slope values computed from 1000-m DEMs are smaller than those computed from 100-m DEMs; specific catchment area and the wetness index are larger for the 1000-m DEMs compared with the 100-m DEMs. Most of the differences between the 100- and 1000-m resolution DEMs can be attributed to terrain-discretization effects in the computation of the topographic characteristics and are not the result of smoothing or loss of terrain detail in the coarse data. In general, the terrain-discretization effects are greatest on flat terrain with long length-scale features, and the smoothing effects are greatest on steep terrain with short length-scale features. For the most part, the differences in the average values of the topographic characteristics computed from 100- and 1000-m resolution DEMs are predictable; that is, biases in the mean values for the characteristics computed from a 1000-m DEM can be corrected with simple linear equations.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrological Processes","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"John Wiley & Sons Ltd","publisherLocation":"Chichester, United Kingdom","doi":"10.1002/(SICI)1099-1085(20000430)14:6<987::AID-HYP980>3.0.CO;2-A","issn":"08856087","usgsCitation":"Wolock, D., and McCabe, G., 2000, Differences in topographic characteristics computed from 100- and 1000-m resolution digital elevation model data: Hydrological Processes, v. 14, no. 6, p. 987-1002, https://doi.org/10.1002/(SICI)1099-1085(20000430)14:6<987::AID-HYP980>3.0.CO;2-A.","startPage":"987","endPage":"1002","numberOfPages":"16","costCenters":[],"links":[{"id":479339,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1002/(sici)1099-1085(20000430)14:6<987::aid-hyp980>3.0.co;2-a","text":"Publisher Index Page"},{"id":206642,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/(SICI)1099-1085(20000430)14:6<987::AID-HYP980>3.0.CO;2-A"},{"id":230446,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"14","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a00f2e4b0c8380cd4f9e2","contributors":{"authors":[{"text":"Wolock, D.M. 0000-0002-6209-938X","orcid":"https://orcid.org/0000-0002-6209-938X","contributorId":36601,"corporation":false,"usgs":true,"family":"Wolock","given":"D.M.","affiliations":[],"preferred":false,"id":392694,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McCabe, G.J. 0000-0002-9258-2997","orcid":"https://orcid.org/0000-0002-9258-2997","contributorId":12961,"corporation":false,"usgs":true,"family":"McCabe","given":"G.J.","affiliations":[],"preferred":false,"id":392693,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ]}