This map is a product of the Black Hills Hydrology Study, which was initiated in 1990 to assess the quantity, quality, and distribution of surface water and groundwater in the Black Hills area of South Dakota (Driscoli, 1992). This long-term study is a cooperative effort between the U.S. Geological Survey (USGS), the South Dakota Department of environment and Natural Resources, and the West Dakota Water development District, which represents various local and county cooperators. This map is part of a series of 1:100,000-scale maps for the study. The maps include a hydrogeologic map, structure-contour maps (altitudes of the tops of formations) for five formations that contain major aquifers in the study area, and potentiometric maps for these five major aquifers (the Inyan Kara. Minnekahta, Minnelusa, Madison, and Deadwood aquifers).
The study area consists of the topographically defined Black Hills and adjacent areas located in western South Dakota. The Black Hills area is an elongated, dome-shaped feature, about 125 miles long and 60 miles wide, which was uplifted during the Laramide orogeny (Feldman and Heimlich, 1980). The oldest geologic units in the study area are Precambrian metamorphic and igneous rocks, which are exposed in the central core of the Black Hills. Surrounding the Precambrian core is a layered series of sedimentary rocks including limestones, sandstones, and shales that are exposed in roughly concentric rings around the uplifted flanks of the Black Hills. The bedrock sedimentary units typically dip away from the uplifted Black Hills at angles that approach or exceed 10 degrees near the outcrops, and decrease with distance from the uplift. Many of the sedimentary units contain aquifers, both within and beyond the study area. Recharge to these aquifers occurs from infiltration of precipitation upon the outcrops and, in some cases, from infiltration of streamflow (Hortness and Driscoll, 1998). Artesian conditions generally exist within these aquifers where an upper confining layer is present. Flowing wells and artesian springs that originate from confined aquifers are common around the periphery of the Black Hills.
The purpose of this map is to show the altitude of the top(structure contours) of the Minnekahta limestone within the area of the Black Hills Hydrology Study. The depth to the top of the Minnekahta Limestone can be estimated at a specific site by subtracting the altitude of the top of the formation from the topographic elevation. However, caution is urged in determining the depth to the top of the formation in areas on the map where the contours are approximately located.
Research on the effects of vegetation manipulation on snowpack, soil water, and streamwater chemistry and flux has been underway at the Fraser Experimental Forest (FEF), CO, since 1982. Greater than 95% of FEF snowmelt passes through watersheds as subsurface flow where soil processes significantly alter meltwater chemistry. To better understand the mechanisms accounting for annual variation in watershed streamwater ion concentration and flux with snowmelt, we studied subsurface water flow, its ion concentration, and flux in conterminous forested and clear cut plots. Repetitive patterns in subsurface flow and chemistry were apparent. Control plot subsurface flow chemistry had the highest ion concentrations in late winter and fall. When shallow subsurface flow occurred, its Ca2+, SO42−, and HCO3− concentrations were lower and K+ higher than deep flow. The percentage of Ca2+, NO3−, SO42−, and HCO3− flux in shallow depths was less and K+ slightly greater than the percentage of total flow. Canopy removal increased precipitation reaching the forest floor by about 40%, increased peak snowpack water equivalent (SWE)>35%, increased the average snowpack Ca2+, NO3−, and NH4+ content, reduced the snowpack K+ content, and increased the runoff four-fold. Clear cutting doubled the percentage of subsurface flow at shallow depths, and increased K+ concentration in shallow subsurface flow and NO3− concentrations in both shallow and deep flow. The percentage change in total Ca2+, SO42−, and HCO3− flux in shallow depths was less than the change in water flux, while that of K+ and NO3− flux was greater. Relative to the control, in the clear cut the percentage of total Ca2+ flux at shallow depths increased from 5 to 12%, SO42− 5·4 to 12%, HCO3− from 5·6 to 8·7%, K+ from 6 to 35%, and NO3− from 2·7 to 17%. The increases in Ca2+ and SO42− flux were proportional to the increase in water flux, the flux of HCO3− increased proportionally less than water flux, and NO3− and K+ were proportionally greater than water flux. Increased subsurface flow accounted for most of the increase in non-limiting nutrient loss. For limiting nutrients, loss of plant uptake and increased shallow subsurface flow accounted for the greater loss. Seasonal ion concentration patterns in streamwater and subsurface flow were similar .
Hydroxyatrazine (HA) is the major metabolite of atrazine in most surface soils. Knowledge of HA sorption to soils, and its pattern of stream water contamination suggest that it is persistent in the environment. Soils with different atrazine use histories were collected from four sites, and sediments were collected from an agricultural watershed. Samples were exhaustively extracted with a mixed—mode extractant, and HA was quantitated using high performance liquid chromatography with UV detection. Atrazine, deethylatrazine (DEA), and deisopropylatrazine (DIA) were also measured in all samples. Concentrations of HA were considerably greater than concentrations of atrazine, DEA, and DIA in all soils and sediments studied. Soil concentrations of HA ranged from 14 to 640 μg/kg with a median concentration of 84 μg/kg. Sediment concentrations of HA ranged from 11 to 96 μg/kg, with a median concentration of 14 μg/kg. Correlations of HA and atrazine concentrations to soil properties indicated that HA levels in soils were controlled by sorption of atrazine. Because atrazine hydrolysis is known to be enhanced by sorption and pH extremes, soils with high organic matter (OM) and clay content and low pH will result in greater atrazine sorption and subsequent hydrolysis. Significant correlation of HA concentrations to OM, pH, and cation exchange capacity of sediments indicated that mixed—mode sorption (i.e., binding by cation exchange and hydrophobic interactions) was the mechanism controlling HA levels in sediment. The presence of HA in soils and stream sediments at the levels observed support existing hypotheses regarding its transport in surface runoff. These results also indicated that persistence of HA in terrestrial and aquatic ecosystems is an additional risk factor associated with atrazine usage.
","language":"English","publisher":"Wiley","doi":"10.1002/etc.5620181007","issn":"07307268","usgsCitation":"Lerch, R., Thurman, E., and Blanchard, P., 1999, Hydroxyatrazine in soils and sediments: Environmental Toxicology and Chemistry, v. 18, no. 10, p. 2161-2168, https://doi.org/10.1002/etc.5620181007.","productDescription":"8 p.","startPage":"2161","endPage":"2168","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230139,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"18","issue":"10","noUsgsAuthors":false,"publicationDate":"1999-10-01","publicationStatus":"PW","scienceBaseUri":"505a37b3e4b0c8380cd610aa","contributors":{"authors":[{"text":"Lerch, R.N.","contributorId":88504,"corporation":false,"usgs":true,"family":"Lerch","given":"R.N.","email":"","affiliations":[],"preferred":false,"id":388986,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":388987,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Blanchard, P.E.","contributorId":76900,"corporation":false,"usgs":true,"family":"Blanchard","given":"P.E.","email":"","affiliations":[],"preferred":false,"id":388985,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021285,"text":"70021285 - 1999 - Enzymatic and histopathologic biomarkers as indicators of contaminant exposure and effect in Asian clam (Potamocorbula amurensis)","interactions":[],"lastModifiedDate":"2018-12-21T06:20:22","indexId":"70021285","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1034,"text":"Biomarkers","active":true,"publicationSubtype":{"id":10}},"title":"Enzymatic and histopathologic biomarkers as indicators of contaminant exposure and effect in Asian clam (Potamocorbula amurensis)","docAbstract":"Enzymatic and histopathologic alterations of the digestive gland, gill, gonad, and kidney were studied in Asian clam (Potamocorbula amurensis) in April, 1997 from each of four United States Geological Survey (USGS) stations in the San Francisco Estuary. Stations were selected based on differing body burdens of metallic contaminants in clams (Stn 4.1>6.1>8.1>12.5) observed over 7 years. Because no pristine sites are known within the estuary and because no laboratory-reared stocks of P. amurensis were available, clams from station 12.5 served as reference animals. Histopathologic analysis revealed no lesions in clams collected from station 12.5. Mild digestive gland atrophy and moderate distal kidney tubular vacuolation were seen in clams collected from station 8.1. Mild digestive gland atrophy, moderate kidney tubular atrophy, and moderate gill inflammation were seen in clams collected from station 6.1. Lesions found only in clams from station 4.1 were: (1) severe inflammation and moderate atrophy of primary ducts and diverticula, and decreased numbers of heterophagosomes and heterolysosomes in diverticula of the digestive gland; (2) severe gill inflammation; (3) severe kidney tubular atrophy; (4) severe ovarian and testicular inflammation and necrosis (5) decreased numbers of mature ova; and (6) decreased number of glycogen storage cells in the ovary and testis. Localization of specific enzymes including adenosine triphosphatase (ATP), acid phosphatase (ACP), alkaline phosphatase (ALKP), gamma-glutamyl transpeptidase (GGT), and glucose-6-phosphate dehydrogenase (G6PDH) was performed and correlated, in serial sections with glycogen (PAS) and haematoxylin and eosin stains. Enzymatic analysis revealed: (1) increased digestive diverticula ATP in stations 6.1 and 4.1; (2) decreased digestive diverticula ACP in stations 6.1 and 4.1 and proximal kidney tubular ACP deficiency in station 4.1; (3) no ALKP differences among stations; (4) increased distal kidney tubular GGT at station 12.5 and decreased distal kidney tubular GGT at station 4.1; (5) decreased digestive diverticula G6PDH G6PDH in all stations except 12.5 and decreased proximal kidney tubular G6PDH in stations 8.1 and 6.1. It is possible that other anthropogenic and natural stressors may have affected the results in this study. However, the prevalence and increased severity of lesions in clams with highest metal body burden suggests a contaminant- associated etiology. Enzymatic and histopathologic biomarker alterations identified in this study were positively correlated with the metal body burden. Clams with the higher prevalence of diseases and enzyme alterations also showed a lower condition index and glycogen content in the month when histopathological assessment was performed. Further study will seek to develop enzymatic and histopathologic biomarkers for use in controlled laboratory conditions to help validate the field study.
","language":"English","publisher":"Taylor and Francis","doi":"10.1080/135475099230660","usgsCitation":"Teh, S., Clark, S., Brown, C.L., Luoma, S., and Hinton, D., 1999, Enzymatic and histopathologic biomarkers as indicators of contaminant exposure and effect in Asian clam (Potamocorbula amurensis): Biomarkers, v. 4, no. 6, p. 497-509, https://doi.org/10.1080/135475099230660.","productDescription":"13 p.","startPage":"497","endPage":"509","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":229946,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"4","issue":"6","noUsgsAuthors":false,"publicationDate":"2008-09-29","publicationStatus":"PW","scienceBaseUri":"505a09f0e4b0c8380cd52110","contributors":{"authors":[{"text":"Teh, S.J.","contributorId":29596,"corporation":false,"usgs":true,"family":"Teh","given":"S.J.","email":"","affiliations":[],"preferred":false,"id":389345,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Clark, S.L.","contributorId":88113,"corporation":false,"usgs":true,"family":"Clark","given":"S.L.","email":"","affiliations":[],"preferred":false,"id":389349,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Brown, C. L.","contributorId":35678,"corporation":false,"usgs":true,"family":"Brown","given":"C.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":389346,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":389348,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Hinton, D.E.","contributorId":75489,"corporation":false,"usgs":true,"family":"Hinton","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":389347,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70021233,"text":"70021233 - 1999 - Importance of microscopy in durability studies of solidified and stabilized contaminated soils","interactions":[],"lastModifiedDate":"2020-09-25T19:44:10.290872","indexId":"70021233","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3420,"text":"Soil Science Society of America Journal","active":true,"publicationSubtype":{"id":10}},"title":"Importance of microscopy in durability studies of solidified and stabilized contaminated soils","docAbstract":"Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical, thermal, or biological means. Despite the increased use of S/S technologies, little research has been conducted on the weathering and degradation of solidified and stabilized wastes once the treated materials have been buried. Published data to verify the performance and durability of landfilled treated wastes over time are rare. In this preliminary study, optical and electron microscopy (scanning electron microscopy [SEM], transmission electron microscopy [TEM] and electron probe microanalyses [EPMA]) were used to evaluate weathering features associated with metal-bearing contaminated soil that had been solidified and stabilized with Portland cement and subsequently buried on site, stored outdoors aboveground, or achieved in a laboratory warehouse for up to 6 yr. Physical and chemical alteration processes identified include: freeze-thaw cracking, cracking caused by the formation of expansive minerals such as ettringite, carbonation, and the movement of metals from waste aggregates into the cement micromass. Although the extent of degradation after 6 yr is considered slight to moderate, results of this study show that the same environmental concerns that affect the durability of concrete must be considered when evaluating the durability and permanence of the solidification and stabilization of contaminated soils with cement. In addition, such evaluations cannot be based on leaching and chemical analyses alone. The use of all levels of microscopic analyses must be incorporated into studies of the long-term performance of S/S technologies.Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical, thermal, or biological means. Despite the increased use of S/S technologies, little research has been conducted on the weathering and degradation of solidified and stabilized wastes once the treated materials have been buried. Published data to verify the performance and durability of landfilled treated wastes over time are rare. In this preliminary study, optical and electron microscopy (scanning electron microscopy [SEM], transmission electron microscopy [TEM] and electron probe microanalyses [EPMA]) were used to evaluate weathering features associated with metal-bearing contaminated soil that had been solidified and stabilized with Portland cement and subsequently buried on site, stored outdoors aboveground, or archived in a laboratory, warehouse for up to 6 yr. Physical and chemical alteration processes identified include: freeze-thaw cracking, cracking caused by the formation of expansive minerals such as ettringite, carbonation, and the movement of metals from waste aggregates into the cement micromass. Although the extent of degradation after 6 yr is considered slight to moderate, results of this study show that the same environmental concerns that affect the durability of concrete must be considered when evaluating the durability and permanence of the solidification and stabilization of contaminated soils with cement. In addition, such evaluations cannot be based on leaching and chemical analyses alone. The use of all levels of microscopic analyses must be incorporated into studies of the long-term performance of S/S technologies.","language":"English","publisher":"Wiley","doi":"10.2136/sssaj1999.6351274x","issn":"03615995","usgsCitation":"Klich, I., Wilding, L., Drees, L., and Landa, E.R., 1999, Importance of microscopy in durability studies of solidified and stabilized contaminated soils: Soil Science Society of America Journal, v. 63, no. 5, p. 1274-1283, https://doi.org/10.2136/sssaj1999.6351274x.","productDescription":"10 p.","startPage":"1274","endPage":"1283","numberOfPages":"10","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":229665,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"63","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a393de4b0c8380cd61863","contributors":{"authors":[{"text":"Klich, I.","contributorId":68911,"corporation":false,"usgs":true,"family":"Klich","given":"I.","email":"","affiliations":[],"preferred":false,"id":389150,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wilding, L.P.","contributorId":74534,"corporation":false,"usgs":true,"family":"Wilding","given":"L.P.","email":"","affiliations":[],"preferred":false,"id":389151,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Drees, L.R.","contributorId":101833,"corporation":false,"usgs":true,"family":"Drees","given":"L.R.","email":"","affiliations":[],"preferred":false,"id":389153,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Landa, E. R.","contributorId":100002,"corporation":false,"usgs":true,"family":"Landa","given":"E.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":389152,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021122,"text":"70021122 - 1999 - Variations in trace element geochemistry in the Seine River Basin based on floodplain deposits and bed sediments","interactions":[],"lastModifiedDate":"2024-03-26T11:18:57.222739","indexId":"70021122","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Variations in trace element geochemistry in the Seine River Basin based on floodplain deposits and bed sediments","docAbstract":"Between 1990 and 1995 a series of bed sediment, suspended sediment and fresh floodplain samples were collected within the Seine River Basin, in France, to evaluate variations in trace element geochemistry. Average background trace element levels for the basin were determined from the collection and subsequent analyses of bed sediment samples from small rural watersheds and from a prehistoric (5000 BP) site in Paris. Concentrations are relatively low, and similar to those observed for fine-grained bed sediments from unaffected areas in the United States and Canada. However, the concentrations are somewhat higher than the reference levels presently adopted by French water authorities for areas north of the Seine Basin, which have similar bedrock lithologies. Downstream trace element variations were monitored in 1994 and 1995 using fresh surficial floodplain samples that were collected either as dried deposits a few days after peak discharge, or immediately after peak discharge (under ≤30 cm of water). Chemical comparisons between fresh floodplain deposits, and actual suspended sediments collected during flood events, indicate that, with some caveats, the former can be used as surrogates for the latter. The floodplain sediment chemical data indicate that within the Seine Basin, from the relatively unaffected headwaters through heavily affected urban streams, trace element concentrations vary by as much as three orders of magnitude. These trace element changes appear to be the result of both increases in population as well as concomitant increases in industrial activity. (This article is a US government work and is in the public domain in the United States.)
This map is a product of the Black Hills Hydrology Study, which was initiated in 1990 to assess the quantity, quality, and distribution of surface water and ground water in the Black Hills area of South Dakota (Driscoll, 1992). This long-term study is a cooperative effort between the U.S. Geological Survey (USGS), the South Dakota Department of Environment and Natural Resources, and the West Dakota Water Development District, which represents various local and county cooperators. This map is part of a series of 1:100,000-scale maps for the study. The maps include a hydrogeologic map, structure-contour maps (altitudes of the tops of formations) for five formations that contain major aquifers in the study area, and potentiometric maps for these five major aquifers (the Inyan Kara, Minnekahta, Minnelusa, Madison, and Deadwood aquifers).
The study area consists of the topographically defined Black Hills and adjacent areas located in western South Dakota. The Black Hills area is an elongated, dome-shaped feature, about 125 miles long and 60 miles wide, which was uplifted during the Laramide orogeny (Feldman and Heimlich, 1980). The oldest geologic units in the study area are Precambrian metamorphic and igneous rocks, which are exposed in the central core of the Black Hills. Surrounding the Precambrian core is a layered series of sedimentary rocks including limestones, sandstones, and shales that are exposed in roughly concentric rings around the uplifted flanks of the Black Hills. The bedrock sedimentary units typically dip away from the uplifted Black Hills at angles that approach or exceed 10 degrees near the outcrops, and decrease with distance from the uplift. Many of the sedimentary units contain aquifers, both within and beyond the study area. Recharge to these aquifers occurs from infiltration of precipitation upon the outcrops and, in some cases, from infiltration of streamflow (Hortness and Driscoll, 1998). Artesian conditions generally exist within these aquifers where an upper confining layer is present. Flowing wells and artesian springs that originate from confined aquifers are common around the periphery of the Black Hills.
The purpose of this map is to show the altitude of the top (structure contours) of the Deadwood Formation within the area of the Black Hills Hydrology Study. The depth to the top of the Deadwood Formation can be estimated at a specific site by subtracting the altitude of the top of the formation from the topographic elevation, However, caution is urged in determining the depth to the top of the formation in areas on the map where the contours are approximately located.
Selenium (Se) can be oxidized by nitrate (NO−3) from irrigation on Cretaceous marine shale in western Colorado. Dissolved Se concentrations are positively correlated with dissolved NO−3concentrations in surface water and ground water samples from irrigated areas. Redox conditions dominate in the mobilization of Se in marine shale hydrogeologic settings; dissolved Se concentrations increase with increasing platinum-electrode potentials. Theoretical calculations for the oxidation of Se by NO−3 and oxygen show favorable Gibbs free energies for the oxidation of Se by NO−3, indicating NO−3 can act as an electron acceptor for the oxidation of Se. Laboratory batch experiments were performed by adding Mancos Shale samples to zero-dissolved-oxygen water containing 0, 5, 50, and 100 mg/L NO−3 as N (mg N/L). Samples were incubated in airtight bottles at 25°C for 188 d; samples collected from the batch experiment bottles show increased Se concentrations over time with increased NO−3 concentrations. Pseudo first-order rate constants for NO−3 oxidation of Se ranged from 0.0007 to 0.0048/d for 0 to 100 mg N/L NO−3 concentrations, respectively. Management of N fertilizer applications in Cretaceous shale settings might help to control the oxidation and mobilization of Se and other trace constituents into the environment.
","language":"English","publisher":"ACSESS","doi":"10.2134/jeq1999.00472425002800040019x","issn":"00472425","usgsCitation":"Wright, W.G., 1999, Oxidation and mobilization of selenium by nitrate in irrigation drainage: Journal of Environmental Quality, v. 28, no. 4, p. 1182-1187, https://doi.org/10.2134/jeq1999.00472425002800040019x.","productDescription":"6 p.","startPage":"1182","endPage":"1187","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":229571,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"28","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7261e4b0c8380cd76a6e","contributors":{"authors":[{"text":"Wright, W. G.","contributorId":19582,"corporation":false,"usgs":true,"family":"Wright","given":"W.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":391844,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70021955,"text":"70021955 - 1999 - Evaluating the use of “goodness‐of‐fit” measures in hydrologic and hydroclimatic model validation","interactions":[],"lastModifiedDate":"2018-03-20T15:26:29","indexId":"70021955","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Evaluating the use of “goodness‐of‐fit” measures in hydrologic and hydroclimatic model validation","docAbstract":"Correlation and correlation‐based measures (e.g., the coefficient of determination) have been widely used to evaluate the “goodness‐of‐fit” of hydrologic and hydroclimatic models. These measures are oversensitive to extreme values (outliers) and are insensitive to additive and proportional differences between model predictions and observations. Because of these limitations, correlation‐based measures can indicate that a model is a good predictor, even when it is not. In this paper, useful alternative goodness‐of‐fit or relative error measures (including the coefficient of efficiency and the index of agreement) that overcome many of the limitations of correlation‐based measures are discussed. Modifications to these statistics to aid in interpretation are presented. It is concluded that correlation and correlation‐based measures should not be used to assess the goodness‐of‐fit of a hydrologic or hydroclimatic model and that additional evaluation measures (such as summary statistics and absolute error measures) should supplement model evaluation tools.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1998WR900018","usgsCitation":"Legates, D.R., and McCabe, G.J., 1999, Evaluating the use of “goodness‐of‐fit” measures in hydrologic and hydroclimatic model validation: Water Resources Research, v. 35, no. 1, p. 233-241, https://doi.org/10.1029/1998WR900018.","productDescription":"9 p.","startPage":"233","endPage":"241","costCenters":[],"links":[{"id":229570,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"35","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0c01e4b0c8380cd529c2","contributors":{"authors":[{"text":"Legates, David R.","contributorId":194273,"corporation":false,"usgs":false,"family":"Legates","given":"David","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":391842,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McCabe, Gregory J. Jr.","contributorId":124577,"corporation":false,"usgs":false,"family":"McCabe","given":"Gregory","suffix":"Jr.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":391843,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021932,"text":"70021932 - 1999 - A record of hydrocarbon input to San Francisco Bay as traced by biomarker profiles in surface sediment and sediment cores","interactions":[],"lastModifiedDate":"2020-01-04T14:46:58","indexId":"70021932","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2662,"text":"Marine Chemistry","active":true,"publicationSubtype":{"id":10}},"title":"A record of hydrocarbon input to San Francisco Bay as traced by biomarker profiles in surface sediment and sediment cores","docAbstract":"San Francisco Bay is one of the world's largest urbanized estuarine systems. Its water and sediment receive organic input from a wide variety of sources; much of this organic material is anthropogenically derived. To document the spatial and historical record of the organic contaminant input, surficial sediment from 17 sites throughout San Francisco Bay and sediment cores from two locations Richardson Bay and San Pablo Bay were analyzed for biomarker constituents. Biomarkers, that is, 'molecular fossils', primarily hopanes, steranes, and n-alkanes, provide information on anthropogenic contamination, especially that related to petrogenic sources, as well as on recent input of biogenic material. The biomarker parameters from the surficial sediment and the upper horizons of the cores show a dominance of anthropogenic input, whereas the biomarker profiles at the lower horizons of the cores indicate primarily biogenic input. In the Richardson Bay core the gradual upcore transition from lower maturity background organics to a dominance of anthropogenic contamination occurred about 70-100 years ago and corresponds to the industrial development of the San Francisco Bay area. In San Pablo Bay, the transition was very abrupt, reflecting the complex depositional history of the area. This sharp transition, perhaps indicating a depositional hiatus or erosional period, dated at pre-1952, is clearly visible. Below, the hiatus the biomarker parameters are immature; above, they are mature and show an anthropogenic overlay. Higher concentrations of terrigenous n-alkanes in the upper horizons in this core are indicative of an increase in terrigenous organic matter input in San Pablo Bay, possibly a result of water diversion projects and changes in the fresh water flow into the Bay from the Delta. Alternatively, it could reflect a dilution of organic material in the lower core sections with hydraulic mining debris.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0304-4203(98)00088-7","issn":"03044203","usgsCitation":"Hostettler, F., Pereira, W.E., Kvenvolden, K., VanGeen, A., Luoma, S., Fuller, C.C., and Anima, R., 1999, A record of hydrocarbon input to San Francisco Bay as traced by biomarker profiles in surface sediment and sediment cores: Marine Chemistry, v. 64, no. 1-2, p. 115-127, https://doi.org/10.1016/S0304-4203(98)00088-7.","productDescription":"13 p.","startPage":"115","endPage":"127","numberOfPages":"13","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":229421,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -123.81591796875,\n 36.56260003738545\n ],\n [\n -120.234375,\n 36.56260003738545\n ],\n [\n -120.234375,\n 39.40224434029275\n ],\n [\n -123.81591796875,\n 39.40224434029275\n ],\n [\n -123.81591796875,\n 36.56260003738545\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"64","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e53ce4b0c8380cd46c12","contributors":{"authors":[{"text":"Hostettler, F. 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The sedimentary record of PAHs in Richardson Bay shows that anthropogenic inputs have increased since the turn of the century, presumably as a result of increasing urbanization and industrialization around the Bay Area. Concentrations range from about 0.04-6.3 ??g g-1. The dominant origin of the PAHs contributing to this modern contamination is from combustion processes. Depth profiles in San Pablo Bay indicate higher concentrations of PAHs since the 1950s than during the late 1800s, also presumably resulting from an increase in urbanization and industrialization. Total PAHs in San Pablo Bay range from about 0.04-1.3 ??g g-1. The ratios of methylphenanthrenes/phenanthrene and (methylfluoranthenes + methylpyrenes)/fluoranthene were sensitive indicators of anthropogenic influences in the estuary. Variations in the ratio of 1,7-dimethylphenanthrene/2,6-dimethylphenanthrene indicate a gradual replacement of wood by fossil-fuel as the main combustion source of PAHs in. San Francisco Bay sediments. The profile of perylene may be an indicator of eroding peat from marshlands.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0304-4203(98)00087-5","issn":"03044203","usgsCitation":"Pereira, W.E., Hostettler, F.D., Luoma, S.N., VanGeen, A., Fuller, C.C., and Anima, R.J., 1999, Sedimentary record of anthropogenic and biogenic polycyclic aromatic hydrocarbons in San Francisco Bay, California: Marine Chemistry, v. 64, no. 1-2, p. 99-113, https://doi.org/10.1016/S0304-4203(98)00087-5.","productDescription":"15 p.","startPage":"99","endPage":"113","numberOfPages":"15","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":229453,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -123.0908203125,\n 37.29153547292737\n ],\n [\n -121.78344726562499,\n 37.29153547292737\n ],\n [\n -121.78344726562499,\n 38.30718056188316\n ],\n [\n -123.0908203125,\n 38.30718056188316\n ],\n [\n -123.0908203125,\n 37.29153547292737\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"64","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8a35e4b08c986b3170b5","contributors":{"authors":[{"text":"Pereira, W. 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We provide some constraints on the onset of these erosional disturbances with 10Be data for three sediment cores: two from Richardson Bay, a small embayment near the mouth of San Francisco Bay, and one from San Pablo Bay, mid-way between the river delta and the mouth. Comparison of pre-disturbance sediment accumulation determined from three 14C-dated mollusk shells in one Richardson Bay core with more recent conditions determined from the distribution of 210Pb and 234Th [Fuller, C.C., van Geen, A., Baskaran, M, Anima, R.J., 1999. Sediment chronology in San Francisco Bay, California, defined by 210Pb, 234Th, 239,240Pu.] shows that the accumulation rate increased by an order of magnitude at this particular site. All three cores from San Francisco Bay show subsurface maxima in 10Be concentrations ranging in magnitude from 170 to 520 x 106 atoms/g. The transient nature of the increased 10Be input suggests that deforestation and agricultural develop- ment caused basin-wide erosion of surface soils enriched in 10Be. probably before the turn of the century.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0304-4203(98)00082-6","issn":"03044203","usgsCitation":"VanGeen, A., Valette-Silver, N.J., Luoma, S., Fuller, C.C., Baskaran, M., Tera, F., and Klein, J., 1999, Constraints on the sedimentation history of San Francisco Bay from 14C and 10Be: Marine Chemistry, v. 64, no. 1-2, p. 29-38, https://doi.org/10.1016/S0304-4203(98)00082-6.","productDescription":"10 p.","startPage":"29","endPage":"38","numberOfPages":"10","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":479503,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1016/s0304-4203(98)00082-6","text":"Publisher Index Page"},{"id":229603,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -123.81591796875,\n 36.56260003738545\n ],\n [\n -120.234375,\n 36.56260003738545\n ],\n [\n -120.234375,\n 39.40224434029275\n ],\n [\n -123.81591796875,\n 39.40224434029275\n ],\n [\n -123.81591796875,\n 36.56260003738545\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"64","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fa0fe4b0c8380cd4d8f7","contributors":{"authors":[{"text":"VanGeen, A.","contributorId":84086,"corporation":false,"usgs":true,"family":"VanGeen","given":"A.","email":"","affiliations":[],"preferred":false,"id":391543,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Valette-Silver, N. J.","contributorId":100140,"corporation":false,"usgs":true,"family":"Valette-Silver","given":"N.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":391547,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":391544,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Fuller, C. C.","contributorId":29858,"corporation":false,"usgs":true,"family":"Fuller","given":"C.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":391542,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Baskaran, M.","contributorId":96627,"corporation":false,"usgs":true,"family":"Baskaran","given":"M.","affiliations":[],"preferred":false,"id":391546,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Tera, F.","contributorId":18102,"corporation":false,"usgs":true,"family":"Tera","given":"F.","email":"","affiliations":[],"preferred":false,"id":391541,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Klein, J.","contributorId":90885,"corporation":false,"usgs":true,"family":"Klein","given":"J.","email":"","affiliations":[],"preferred":false,"id":391545,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70021864,"text":"70021864 - 1999 - Carbon isotopic constraints on the contribution of plant material to the natural precursors of trihalomethanes","interactions":[],"lastModifiedDate":"2018-12-14T07:32:15","indexId":"70021864","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2958,"text":"Organic Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Carbon isotopic constraints on the contribution of plant material to the natural precursors of trihalomethanes","docAbstract":"The δ13C values of individual trihalomethanes (THM) formed on reaction of chlorine with dissolved organic carbon (DOC) leached from maize (corn; Zea maize L.) and Scirpus acutus(an aquatic bulrush), and with DOC extracted from agricultural drainage waters were determined using purge and trap introduction into a gas chromatograph-combustion-isotope ratio monitoring mass spectrometer. We observed a 16.8‰ difference between the δ13C values of THM produced from the maize and Scirpus leachates, similar to the isotopic difference between the whole plant materials. Both maize and Scirpus formed THM 12‰ lower in 13C than whole plant material. We suggest that the low value of the THM relative to the whole plant material is evidence of distinct pools of THM-forming DOC, representing different biochemical types or chemical structures, and possessing different environmental reactivity.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0146-6380(99)00066-2","issn":"01466380","usgsCitation":"Bergamaschi, B., Fram, M., Kendall, C., Silva, S.R., Aiken, G., and Fujii, R., 1999, Carbon isotopic constraints on the contribution of plant material to the natural precursors of trihalomethanes: Organic Geochemistry, v. 30, no. 8 A, p. 835-842, https://doi.org/10.1016/S0146-6380(99)00066-2.","productDescription":"8 p.","startPage":"835","endPage":"842","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":229340,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206298,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0146-6380(99)00066-2"}],"volume":"30","issue":"8 A","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f368e4b0c8380cd4b7bb","contributors":{"authors":[{"text":"Bergamaschi, B.A. 0000-0002-9610-5581","orcid":"https://orcid.org/0000-0002-9610-5581","contributorId":22401,"corporation":false,"usgs":true,"family":"Bergamaschi","given":"B.A.","affiliations":[],"preferred":false,"id":391476,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fram, M.S. 0000-0002-6337-059X","orcid":"https://orcid.org/0000-0002-6337-059X","contributorId":88406,"corporation":false,"usgs":true,"family":"Fram","given":"M.S.","affiliations":[],"preferred":false,"id":391480,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kendall, C. 0000-0002-0247-3405","orcid":"https://orcid.org/0000-0002-0247-3405","contributorId":35050,"corporation":false,"usgs":true,"family":"Kendall","given":"C.","affiliations":[],"preferred":false,"id":391479,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Silva, S. R.","contributorId":27474,"corporation":false,"usgs":true,"family":"Silva","given":"S.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":391477,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Aiken, G. R. 0000-0001-8454-0984","orcid":"https://orcid.org/0000-0001-8454-0984","contributorId":14452,"corporation":false,"usgs":true,"family":"Aiken","given":"G. R.","affiliations":[],"preferred":false,"id":391475,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Fujii, R.","contributorId":32278,"corporation":false,"usgs":true,"family":"Fujii","given":"R.","email":"","affiliations":[],"preferred":false,"id":391478,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70022194,"text":"70022194 - 1999 - Simulations of snow distribution and hydrology in a mountain basin","interactions":[],"lastModifiedDate":"2018-03-16T10:16:46","indexId":"70022194","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Simulations of snow distribution and hydrology in a mountain basin","docAbstract":"We applied a version of the Regional Hydro-Ecologic Simulation System (RHESSys) that implements snow redistribution, elevation partitioning, and wind-driven sublimation to Loch Vale Watershed (LVWS), an alpine-subalpine Rocky Mountain catchment where snow accumulation and ablation dominate the hydrologic cycle. We compared simulated discharge to measured discharge and the simulated snow distribution to photogrammetrically rectified aerial (remotely sensed) images. Snow redistribution was governed by a topographic similarity index. We subdivided each hillslope into elevation bands that had homogeneous climate extrapolated from observed climate. We created a distributed wind speed field that was used in conjunction with daily measured wind speeds to estimate sublimation. Modeling snow redistribution was critical to estimating the timing and magnitude of discharge. Incorporating elevation partitioning improved estimated timing of discharge but did not improve patterns of snow cover since wind was the dominant controller of areal snow patterns. Simulating wind-driven sublimation was necessary to predict moisture losses.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1998WR900096","usgsCitation":"Hartman, M.D., Baron, J., Lammers, R.B., Cline, D., Band, L.E., Liston, G.E., and Tague, C.L., 1999, Simulations of snow distribution and hydrology in a mountain basin: Water Resources Research, v. 35, no. 5, p. 1587-1603, https://doi.org/10.1029/1998WR900096.","productDescription":"17 p.","startPage":"1587","endPage":"1603","costCenters":[],"links":[{"id":479642,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/1998wr900096","text":"Publisher Index Page"},{"id":230329,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"35","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b90cbe4b08c986b319675","contributors":{"authors":[{"text":"Hartman, Melannie D.","contributorId":98836,"corporation":false,"usgs":true,"family":"Hartman","given":"Melannie","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":392671,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Baron, Jill 0000-0002-5902-6251 jill_baron@usgs.gov","orcid":"https://orcid.org/0000-0002-5902-6251","contributorId":194124,"corporation":false,"usgs":true,"family":"Baron","given":"Jill","email":"jill_baron@usgs.gov","affiliations":[{"id":291,"text":"Fort Collins Science Center","active":true,"usgs":true}],"preferred":true,"id":392673,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lammers, Richard B.","contributorId":169796,"corporation":false,"usgs":false,"family":"Lammers","given":"Richard","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":392674,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Cline, Donald W.","contributorId":193495,"corporation":false,"usgs":false,"family":"Cline","given":"Donald W.","affiliations":[],"preferred":false,"id":392677,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Band, Larry E.","contributorId":193494,"corporation":false,"usgs":false,"family":"Band","given":"Larry","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":392675,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Liston, Glen E.","contributorId":26244,"corporation":false,"usgs":true,"family":"Liston","given":"Glen","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":392676,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Tague, Christina L.","contributorId":54493,"corporation":false,"usgs":true,"family":"Tague","given":"Christina","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":392672,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70021845,"text":"70021845 - 1999 - Chemical weathering in a tropical watershed, Luquillo Mountains, Puerto Rico III: Quartz dissolution rates","interactions":[],"lastModifiedDate":"2012-03-12T17:19:37","indexId":"70021845","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Chemical weathering in a tropical watershed, Luquillo Mountains, Puerto Rico III: Quartz dissolution rates","docAbstract":"The paucity of weathering rates for quartz in the natural environment stems both from the slow rate at which quartz dissolves and the difficulty in differentiating solute Si contributed by quartz from that derived from other silicate minerals. This study, a first effort in quantifying natural rates of quartz dissolution, takes advantage of extremely rapid tropical weathering, simple regolith mineralogy, and detailed information on hydrologic and chemical transport. Quartz abundances and grain sizes are relatively constant with depth in a thick saprolite. Limited quartz dissolution is indicated by solution rounding of primary angularity and by the formation of etch pits. A low correlation of surface area (0.14 and 0.42 m2 g-1) with grain size indicates that internal microfractures and pitting are the principal contributors to total surface area. Pore water silica concentration increases linearly with depth. On a molar basis, between one and three quarters of pore water silica is derived from quartz with the remainder contributed from biotite weathering. Average solute Si remains thermodynamically undersaturated with respect to recently revised estimates of quartz solubility (<180 ??M) but exceeds estimated critical saturation concentrations controlling the initiation of etch pit formation (>17-81 ??M). Etch pitting is more abundant on grains in the upper saprolite and is associated with pore waters lower in dissolved silica. Rate constants describing quartz dissolution increase with decreasing depth (from 10-14.5-10-15.1 mol m-2 s-1), which correlate with both greater thermodynamic undersaturation and increasing etch pit densities. Unlike for many aluminosilicates, the calculated natural weathering rates of quartz fall slightly below the rate constants previously reported for experimental studies (10-12.4-10-14.2 mol m-2 s-1). This agreement reflects the structural simplicity of quartz, dilute solutes, and near-hydrologic saturation.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Geochimica et Cosmochimica Acta","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0016-7037(99)00056-3","issn":"00167037","usgsCitation":"Schulz, M.S., and White, A.F., 1999, Chemical weathering in a tropical watershed, Luquillo Mountains, Puerto Rico III: Quartz dissolution rates: Geochimica et Cosmochimica Acta, v. 63, no. 3-4, p. 337-350, https://doi.org/10.1016/S0016-7037(99)00056-3.","startPage":"337","endPage":"350","numberOfPages":"14","costCenters":[],"links":[{"id":206385,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0016-7037(99)00056-3"},{"id":229600,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"63","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f598e4b0c8380cd4c2e8","contributors":{"authors":[{"text":"Schulz, M. 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Total DDTs (DDT = 2,4'- and 4,4'-dichlorodiphenyltrichloroethane and the metabolites, 2,4'- and 4,4'-DDE, -DDD) range in concentration from 4-21 ng/g and constitute a major fraction (> 84%) of the total pesticides in the top 70 cm of Richardson Bay sediment. A subsurface maximum corresponds to a peak deposition date of 1969-1974. The first measurable DDT levels are found in sediment deposited in the late 1930's. The higher DDT inventory in the San Pablo relative to the Richardson Bay core probably reflects the greater proximity of San Pablo Bay to agricultural activities in the watershed of the Sacramento and San Joaquin rivers. Total polychlorinated biphenyls (PCBs) occur at comparable levels in the two Bays (< 1-34 ng/g). PCBs are first detected in sediment deposited during the 1930's in Richardson Bay, about a decade earlier than the onset of detectable levels of DDTs. PCB inventories in San Pablo Bay are about a factor of four higher in the last four decades than in Richardson Bay, suggesting a distribution of inputs not as strongly weighed towards the upper reaches of the estuary as DDTs. The shallower subsurface maximum in PCBs compared to DDT in the San Pablo Bay core is consistent with the imposition of drastic source control measures four these constituents in 1970 and 1977 respectively. The observed decline in DDT and PCB levels towards the surface of both cores is consistent with a dramatic drop in the input of these pollutants once the effect of sediment resuspension and mixing is taken into account.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0304-4203(98)90086-X","issn":"03044203","usgsCitation":"Venkatesan, M., De Leon, R.P., VanGeen, A., and Luoma, S.N., 1999, Chlorinated hydrocarbon pesticides and polychlorinated biphenyls in sediment cores from San Francisco Bay: Marine Chemistry, v. 64, no. 1-2, p. 85-97, https://doi.org/10.1016/S0304-4203(98)90086-X.","productDescription":"13 p.","startPage":"85","endPage":"97","numberOfPages":"13","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":229526,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206359,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0304-4203(98)90086-X"}],"country":"United States","state":"California","otherGeospatial":"San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -123.0908203125,\n 37.29153547292737\n ],\n [\n -121.78344726562499,\n 37.29153547292737\n ],\n [\n -121.78344726562499,\n 38.30718056188316\n ],\n [\n -123.0908203125,\n 38.30718056188316\n ],\n [\n -123.0908203125,\n 37.29153547292737\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"64","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f5c8e4b0c8380cd4c3fb","contributors":{"authors":[{"text":"Venkatesan, M.I.","contributorId":12998,"corporation":false,"usgs":true,"family":"Venkatesan","given":"M.I.","email":"","affiliations":[],"preferred":false,"id":391258,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"De Leon, R. 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Two-component isotopic hydrograph separation showed that event-water contributions near the time of peakflow ranged from 49% to 62% in the 7 catchments during the highest intensity event. The proportion of event water in stormflow was greater than could be accounted for by direct precipitation onto saturated areas. DOC concentrations in stormflow were strongly correlated with stream 18O composition. Bivariate mixing diagrams indicated that the large event water contributions were likely derived from flow through the soil O-horizon. Results from two-tracer, three-component hydrograph separations showed that the throughfall and O-horizon soil-water components together could account for the estimated contributions of event water to stormflow. End-member mixing analysis confirmed these results. Estimated event-water contributions were inversely related to catchment size, but the relation was significant for only the event with greatest rainfall intensity. Our results suggest that perched, shallow subsurface flow provides a substantial contribution to summer stormflow in these small catchments, but the relative contribution of this component decreases with catchment size.Seven nested headwater catchments (8 to 161 ha) were monitored during five summer rain events to evaluate storm runoff components and the effect of catchment size on water sources. Two-component isotopic hydrograph separation showed that event-water contributions near the time of peakflow ranged from 49% to 62% in the 7 catchments during the highest intensity event. The proportion of event water in stormflow was greater than could be accounted for by direct precipitation onto saturated areas. DOC concentrations in stormflow were strongly correlated with stream 18O composition. Bivariate mixing diagrams indicated that the large event water contributions were likely derived from flow through the soil O-horizon. Results from two-tracer, three-component hydrograph separations showed that the throughfall and O-horizon soil-water components together could account for the estimated contributions of event water to stormflow. End-member mixing analysis confirmed these results. Estimated event-water contributions were inversely related to catchment size, but the relation was significant for only the event with greatest rainfall intensity. Our results suggest that perched, shallow subsurface flow provides a substantial contribution to summer stormflow in these small catchments, but the relative contribution of this component decreases with catchment size.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"conferenceTitle":"Proceedings of the 1997 Fifth Scientific Assembley of the International Association of Hydrological Sciences, IAHS-97","conferenceDate":"28 April 1997 through 29 April 1997","conferenceLocation":"Rabat","language":"English","publisher":"Elsevier Science B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0022-1694(98)00247-9","issn":"00221694","usgsCitation":"Brown, V., McDonnell, J.J., Burns, D.A., and Kendall, C., 1999, The role of event water, a rapid shallow flow component, and catchment size in summer stormflow: Journal of Hydrology, v. 217, no. 3-4, p. 171-190, https://doi.org/10.1016/S0022-1694(98)00247-9.","startPage":"171","endPage":"190","numberOfPages":"20","costCenters":[],"links":[{"id":229264,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206266,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(98)00247-9"}],"volume":"217","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baf6be4b08c986b3247a0","contributors":{"authors":[{"text":"Brown, V.A.","contributorId":64414,"corporation":false,"usgs":true,"family":"Brown","given":"V.A.","email":"","affiliations":[],"preferred":false,"id":391186,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McDonnell, Jeffery J. 0000-0002-3880-3162","orcid":"https://orcid.org/0000-0002-3880-3162","contributorId":62723,"corporation":false,"usgs":false,"family":"McDonnell","given":"Jeffery","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":391185,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Burns, Douglas A. 0000-0001-6516-2869","orcid":"https://orcid.org/0000-0001-6516-2869","contributorId":29450,"corporation":false,"usgs":true,"family":"Burns","given":"Douglas","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":391183,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kendall, C. 0000-0002-0247-3405","orcid":"https://orcid.org/0000-0002-0247-3405","contributorId":35050,"corporation":false,"usgs":true,"family":"Kendall","given":"C.","affiliations":[],"preferred":false,"id":391184,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021753,"text":"70021753 - 1999 - Simulating the water balance of the Aral Sea with a coupled regional climate-lake model","interactions":[],"lastModifiedDate":"2024-05-02T16:24:19.700447","indexId":"70021753","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2316,"text":"Journal of Geophysical Research D: Atmospheres","active":true,"publicationSubtype":{"id":10}},"title":"Simulating the water balance of the Aral Sea with a coupled regional climate-lake model","docAbstract":"Before coupled atmosphere-lake models can be used to study the response of large lake systems to climatic forcings, we must first evaluate how well they simulate the water balance and associated lake atmosphere interactions under present-day conditions. We evaluate the hydrology simulated by a lake model coupled to NCAR's regional climate model (RegCM2) in a study of the Aral Sea. The meteorological variables that are input to the lake model are simulated well by RegCM2. Simulated surface air temperatures closely match observed values, except during spring and fall when the simulated temperatures are too cold. The magnitude of precipitation is too high in the region surrounding the Aral Sea during summer and fall. On a yearly basis, RegCM2 produces a reasonable amount of runoff throughout the drainage basin. The lake model coupled to RegCM2 accurately simulates Aral Sea surface temperatures (SSTs). The lake model also simulates observed mid-winter ice fraction well, although the onset of ice growth occurs too late in the year and the ice melts too rapidly in the spring. The simulated annual evaporation from the Aral Sea is consistent with observed estimates; however, the simulated evaporation is greater than observed during summer and less than observed during winter. In a “stand-alone” lake model simulation, the simulated Aral Sea hydrology does not match observations as closely as in the coupled model experiment. These results suggest that a stand-alone lake model would not accurately simulate the hydrologic response of the Aral Sea to various forcings.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98JD02348","issn":"01480227","usgsCitation":"Small, E., Sloan, L., Hostetler, S., and Giorgi, F., 1999, Simulating the water balance of the Aral Sea with a coupled regional climate-lake model: Journal of Geophysical Research D: Atmospheres, v. 104, no. D6, p. 6583-6602, https://doi.org/10.1029/98JD02348.","productDescription":"20 p.","startPage":"6583","endPage":"6602","numberOfPages":"20","costCenters":[],"links":[{"id":479458,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/98jd02348","text":"Publisher Index Page"},{"id":229263,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"104","issue":"D6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8fdee4b08c986b3191b3","contributors":{"authors":[{"text":"Small, E.E.","contributorId":56403,"corporation":false,"usgs":true,"family":"Small","given":"E.E.","email":"","affiliations":[],"preferred":false,"id":391018,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sloan, L.C.","contributorId":83688,"corporation":false,"usgs":true,"family":"Sloan","given":"L.C.","email":"","affiliations":[],"preferred":false,"id":391019,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hostetler, S. 0000-0003-2272-8302","orcid":"https://orcid.org/0000-0003-2272-8302","contributorId":30336,"corporation":false,"usgs":true,"family":"Hostetler","given":"S.","affiliations":[],"preferred":false,"id":391017,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Giorgi, F.","contributorId":24924,"corporation":false,"usgs":false,"family":"Giorgi","given":"F.","affiliations":[],"preferred":false,"id":391016,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021751,"text":"70021751 - 1999 - Influence of diameter on particle transport in a fractured shale saprolite","interactions":[],"lastModifiedDate":"2012-03-12T17:19:37","indexId":"70021751","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Influence of diameter on particle transport in a fractured shale saprolite","docAbstract":"Experiments in an undisturbed, saturated column of weathered and fractured shale saprolite using fluorescent carboxylate-coated latex microspheres as tracers indicate that particle diameter plays a major role in controlling transport. In this study the optimum microsphere diameter for transport was approximately 0.5 ??m. Microspheres larger than the optimum size were present in the effluent at lower relative concentrations, apparently because of greater retention due to gravitational settling and/or physical straining. The smaller than optimum microspheres also experienced greater retention, apparently related to their higher rates of diffusion. Faster diffusion can lead to more frequent collisions with, and attachment to, fracture walls and may also lead to movement of particles into zones of relatively immobile pore water in the fractures or in the fine pore structure of the clay-rich matrix between fractures. Dismantling of the soil column and mapping of the distribution of retained microspheres indicated that there was substantial size-segregation of the microspheres between different fractures or in 'channels' within a fracture. Examination of small core samples showed that the smallest microspheres (0.05-0.1 ??m) were present in the fine pores of the matrix at distances of up to 3-4 mm from the nearest fracture, which supports the hypothesis that small particles can be retained by diffusion into the matrix. Calculations of settling velocity and diffusion rate using simple 1D approaches suggest that these processes could both cause significant retention of the larger and smaller particles, respectively, even for the fast advective transport rates (up to 32 m/day) observed during the experiments. Copyright (C) 1999 Elsevier Science B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0169-7722(98)00156-9","issn":"01697722","usgsCitation":"Cumbie, D., and McKay, L., 1999, Influence of diameter on particle transport in a fractured shale saprolite: Journal of Contaminant Hydrology, v. 37, no. 1-2, p. 139-157, https://doi.org/10.1016/S0169-7722(98)00156-9.","startPage":"139","endPage":"157","numberOfPages":"19","costCenters":[],"links":[{"id":206252,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0169-7722(98)00156-9"},{"id":229224,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"37","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3b21e4b0c8380cd62265","contributors":{"authors":[{"text":"Cumbie, D.H.","contributorId":78497,"corporation":false,"usgs":true,"family":"Cumbie","given":"D.H.","email":"","affiliations":[],"preferred":false,"id":391013,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McKay, L.D.","contributorId":10185,"corporation":false,"usgs":true,"family":"McKay","given":"L.D.","email":"","affiliations":[],"preferred":false,"id":391012,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ]}