The stereoisomers of metolachlor and its two polar metabolites [ethane sulfonic acid (ESA) and oxanilic acid (OXA)] were separated using liquid chromatography–mass spectrometry (LC–MS) and capillary zone electrophoresis (CZE), respectively. The separation of metolachlor enantiomers was achieved using a LC–MS equipped with a chiral stationary phase based on cellulose tris(3,5-dimethylphenyl carbamate) and an atmospheric pressure chemical ionization source operated under positive ion mode. The enantiomers of ESA and OXA were separated using CZE with gamma-cyclodextrin (γ-CD) as chiral selector. Various CZE conditions were investigated to achieve the best resolution of the ESA and OXA enantiomers. The optimum background CZE electrolyte was found to consist of borate buffer (pH = 9) containing 20% methanol (v/v) and 2.5% γ-CD (w/v). Maximum resolution of ESA and OXA enantiomers was achieved using a capillary temperature of 15 °C and applied voltage of 30 kV. The applicability of the LC–MS and CZE methods was demonstrated successfully on the enantiomeric analysis of metolachlor and its metabolites in samples from a soil and water degradation study that was set up to probe the stereoselectivity of metolachlor biodegradation. These techniques allow the enantiomeric ratios of the target analytes to be followed over time during the degradation process and thus will prove useful in determining the role of chirality in pesticide degradation and metabolite formation.
To characterize the linear adsorption phenomena in aqueous nonionic organic solute−mineral systems, the adsorption isotherms of some low-molecular-weight nonpolar nonionic solutes (1,2,3-trichlorobenzene, lindane, phenanthrene, and pyrene) and polar nonionic solutes (1,3-dinitrobenzene and 2,4-dinitrotoluene) from single- and binary-solute solutions on hydrophilic silica and alumina were established. Toward this objective, the influences of temperature, ionic strength, and pH on adsorption were also determined. It is found that linear adsorption exhibits low exothermic heats and practically no adsorptive competition. The solute−solid configuration and the adsorptive force consistent with these effects were hypothesized. For nonpolar solutes, the adsorption occurs presumably by London (dispersion) forces onto a water film above the mineral surface. For polar solutes, the adsorption is also assisted by polar-group interactions. The reduced adsorptive forces of solutes with hydrophilic minerals due to physical separation by the water film and the low fractions of the water-film surface covered by solutes offer a theoretical basis for linear solute adsorption, low exothermic heats, and no adsorptive competition. The postulated adsorptive forces are supported by observations that ionic strength or pH poses no effect on the adsorption of nonpolar solutes while it exhibits a significant effect on the uptake of polar solutes.
Acid mine drainage (AMD) contaminates thousands of kilometers of stream in the western United States. At the same time, nitrogen loading to many mountain watersheds is increasing because of atmospheric deposition of nitrate and increased human use. Relatively little is known about nitrogen cycling in acidic, heavy-metal-laden streams; however, it has been reported that one key process, denitrification, is inhibited under low pH conditions. The objective of this research was to investigate the capacity for denitrification in acidified streams. Denitrification potential was assessed in sediments from several Colorado AMD-impacted streams, ranging from pH 2.60 to 4.54, using microcosm incubations with fresh sediment. Added nitrate was immediately reduced to nitrogen gas without a lag period, indicating that denitrification enzymes were expressed and functional in these systems. First-order denitrification potential rate constants varied from 0.046 to 2.964 day−1. The pH of the microcosm water increased between 0.23 and 1.49 pH units during denitrification. Additional microcosm studies were conducted to examine the effects of initial pH, various electron donors, and iron (added as ferrous and ferric iron). Decreasing initial pH decreased denitrification; however, increasing pH had little effect on denitrification rates. The addition of ferric and ferrous iron decreased observed denitrification potential rate constants. The addition of glucose and natural organic matter stimulated denitrification potential. The addition of hydrogen had little effect, however, and denitrification activity in the microcosms decreased after acetate addition. These results suggest that denitrification can occur in AMD streams, and if stimulated within the environment, denitrification might reduce acidity.
Ultra-clean sampling methods and approaches typically used in pristine environments were applied to quantify concentrations of Hg species in water and microbial biomass from hot springs of Yellowstone National Park, features that are geologically enriched with Hg. Microbial populations of chemically-diverse hot springs were also characterized using modern methods in molecular biology as the initial step toward ongoing work linking Hg speciation with microbial processes. Molecular methods (amplification of environmental DNA using 16S rDNA primers, cloning, denatured gradient gel electrophoresis (DGGE) screening of clone libraries, and sequencing of representative clones) were used to examine the dominant members of microbial communities in hot springs. Total Hg (THg), monomethylated Hg (MeHg), pH, temperature, and other parameters influential to Hg speciation and microbial ecology are reported for hot springs water and associated microbial mats.
","language":"English","publisher":"Elsevier","doi":"10.1016/j.apgeochem.2006.08.004","issn":"08832927","usgsCitation":"King, S., Behnke, S., Slack, K., Krabbenhoft, D., Nordstrom, D.K., Burr, M., and Striegl, R.G., 2006, Mercury in water and biomass of microbial communities in hot springs of Yellowstone National Park, USA: Applied Geochemistry, v. 21, no. 11, p. 1868-1879, https://doi.org/10.1016/j.apgeochem.2006.08.004.","productDescription":"12 p.","startPage":"1868","endPage":"1879","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":236523,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":209804,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.apgeochem.2006.08.004"}],"volume":"21","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a541fe4b0c8380cd6ceb0","contributors":{"authors":[{"text":"King, S.A.","contributorId":74562,"corporation":false,"usgs":true,"family":"King","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":420724,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Behnke, S.","contributorId":62394,"corporation":false,"usgs":true,"family":"Behnke","given":"S.","email":"","affiliations":[],"preferred":false,"id":420722,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Slack, K.","contributorId":94484,"corporation":false,"usgs":true,"family":"Slack","given":"K.","affiliations":[],"preferred":false,"id":420727,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Krabbenhoft, D. P. 0000-0003-1964-5020","orcid":"https://orcid.org/0000-0003-1964-5020","contributorId":90765,"corporation":false,"usgs":true,"family":"Krabbenhoft","given":"D. P.","affiliations":[],"preferred":false,"id":420726,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"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":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":false,"id":420725,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Burr, M.D.","contributorId":58450,"corporation":false,"usgs":true,"family":"Burr","given":"M.D.","email":"","affiliations":[],"preferred":false,"id":420721,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Striegl, Robert G. 0000-0002-8251-4659 rstriegl@usgs.gov","orcid":"https://orcid.org/0000-0002-8251-4659","contributorId":1630,"corporation":false,"usgs":true,"family":"Striegl","given":"Robert","email":"rstriegl@usgs.gov","middleInitial":"G.","affiliations":[{"id":200,"text":"Coop Res Unit Seattle","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},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":false,"id":420723,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70028945,"text":"70028945 - 2006 - Possible linkages between lignite aquifers, pathogenic microbes, and renal pelvic cancer in northwestern Louisiana, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:20:59","indexId":"70028945","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1538,"text":"Environmental Geochemistry and Health","active":true,"publicationSubtype":{"id":10}},"title":"Possible linkages between lignite aquifers, pathogenic microbes, and renal pelvic cancer in northwestern Louisiana, USA","docAbstract":"In May and September, 2002, 14 private residential drinking water wells, one dewatering well at a lignite mine, eight surface water sites, and lignite from an active coal mine were sampled in five Parishes of northwestern Louisiana, USA. Using a geographic information system (GIS), wells were selected that were likely to draw water that had been in contact with lignite; control wells were located in areas devoid of lignite deposits. Well water samples were analyzed for pH, conductivity, organic compounds, and nutrient and anion concentrations. All samples were further tested for presence of fungi (cultures maintained for up to 28 days and colonies counted and identified microscopically) and for metal and trace element concentration by inductively-coupled plasma mass spectrometry and atomic emission spectrometry. Surface water samples were tested for dissolved oxygen and presence of pathogenic leptospiral bacteria. The Spearman correlation method was used to assess the association between the endpoints for these field/laboratory analyses and incidence of cancer of the renal pelvis (RPC) based on data obtained from the Louisiana Tumor Registry for the five Parishes included in the study. Significant associations were revealed between the cancer rate and the presence in drinking water of organic compounds, the fungi Zygomycetes, the nutrients PO4 and NH3, and 13 chemical elements. Presence of human pathogenic leptospires was detected in four out of eight (50%) of the surface water sites sampled. The present study of a stable rural population examined possible linkages between aquifers containing chemically reactive lignite deposits, hydrologic conditions favorable to the leaching and transport of toxic organic compounds from the lignite into the groundwater, possible microbial contamination, and RPC risk. ?? Springer Science+Business Media B.V. 2006.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Geochemistry and Health","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10653-006-9056-y","issn":"02694042","usgsCitation":"Bunnell, J., Tatu, C., Bushon, R., Stoeckel, D.M., Brady, A., Beck, M., Lerch, H., McGee, B., Hanson, B., Shi, R., and Orem, W., 2006, Possible linkages between lignite aquifers, pathogenic microbes, and renal pelvic cancer in northwestern Louisiana, USA: Environmental Geochemistry and Health, v. 28, no. 6, p. 577-587, https://doi.org/10.1007/s10653-006-9056-y.","startPage":"577","endPage":"587","numberOfPages":"11","costCenters":[],"links":[{"id":477490,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1007/s10653-006-9056-y","text":"Publisher Index Page"},{"id":236390,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":209705,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10653-006-9056-y"}],"volume":"28","issue":"6","noUsgsAuthors":false,"publicationDate":"2006-11-21","publicationStatus":"PW","scienceBaseUri":"505a7e29e4b0c8380cd7a3a2","contributors":{"authors":[{"text":"Bunnell, J.E.","contributorId":63512,"corporation":false,"usgs":true,"family":"Bunnell","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":420663,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tatu, C. A.","contributorId":89942,"corporation":false,"usgs":false,"family":"Tatu","given":"C. A.","affiliations":[],"preferred":false,"id":420669,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bushon, R.N.","contributorId":68086,"corporation":false,"usgs":true,"family":"Bushon","given":"R.N.","affiliations":[],"preferred":false,"id":420664,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Stoeckel, D. M.","contributorId":84855,"corporation":false,"usgs":true,"family":"Stoeckel","given":"D.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":420667,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Brady, A.M.G.","contributorId":9834,"corporation":false,"usgs":true,"family":"Brady","given":"A.M.G.","email":"","affiliations":[],"preferred":false,"id":420661,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Beck, M.","contributorId":88544,"corporation":false,"usgs":true,"family":"Beck","given":"M.","affiliations":[],"preferred":false,"id":420668,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Lerch, H.E.","contributorId":100371,"corporation":false,"usgs":true,"family":"Lerch","given":"H.E.","email":"","affiliations":[],"preferred":false,"id":420671,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"McGee, B.","contributorId":78522,"corporation":false,"usgs":true,"family":"McGee","given":"B.","email":"","affiliations":[],"preferred":false,"id":420666,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Hanson, B.C.","contributorId":58828,"corporation":false,"usgs":true,"family":"Hanson","given":"B.C.","email":"","affiliations":[],"preferred":false,"id":420662,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Shi, R.","contributorId":69345,"corporation":false,"usgs":true,"family":"Shi","given":"R.","email":"","affiliations":[],"preferred":false,"id":420665,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Orem, W. H. 0000-0003-4990-0539","orcid":"https://orcid.org/0000-0003-4990-0539","contributorId":93084,"corporation":false,"usgs":true,"family":"Orem","given":"W. H.","affiliations":[],"preferred":false,"id":420670,"contributorType":{"id":1,"text":"Authors"},"rank":11}]}} ,{"id":70030381,"text":"70030381 - 2006 - Evaluation of gridded snow water equivalent and satellite snow cover products for mountain basins in a hydrologic model","interactions":[],"lastModifiedDate":"2012-03-12T17:21:03","indexId":"70030381","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Evaluation of gridded snow water equivalent and satellite snow cover products for mountain basins in a hydrologic model","docAbstract":"The USGS precipitation-runoff modelling system (PRMS) hydrologic model was used to evaluate experimental, gridded, 1 km2 snow-covered area (SCA) and snow water equivalent (SWE) products for two headwater basins within the Rio Grande (i.e. upper Rio Grande River basin) and Salt River (i.e. Black River basin) drainages in the southwestern USA. The SCA product was the fraction of each 1 km2 pixel covered by snow and was derived from NOAA advanced very high-resolution radiometer imagery. The SWE product was developed by multiplying the SCA product by SWE estimates interpolated from National Resources Conservation Service snow telemetry point measurements for a 6 year period (1995-2000). Measured SCA and SWE estimates were consistently lower than values estimated from temperature and precipitation within PRMS. The greatest differences occurred in the relatively complex terrain of the Rio Grande basin, as opposed to the relatively homogeneous terrain of the Black River basin, where differences were small. Differences between modelled and measured snow were different for the accumulation period versus the ablation period and had an elevational trend. Assimilating the measured snowfields into a version of PRMS calibrated to achieve water balance without assimilation led to reduced performance in estimating streamflow for the Rio Grande and increased performance in estimating streamflow for the Black River basin. Correcting the measured SCA and SWE for canopy effects improved simulations by adding snow mostly in the mid-to-high elevations, where satellite estimates of SCA are lower than model estimates. Copyright ?? 2006 John Wiley & Sons, Ltd.","largerWorkTitle":"Hydrological Processes","language":"English","doi":"10.1002/hyp.6130","issn":"08856087","usgsCitation":"Dressler, K., Leavesley, G., Bales, R., and Fassnacht, S., 2006, Evaluation of gridded snow water equivalent and satellite snow cover products for mountain basins in a hydrologic model, in Hydrological Processes, v. 20, no. 4, p. 673-688, https://doi.org/10.1002/hyp.6130.","startPage":"673","endPage":"688","numberOfPages":"16","costCenters":[],"links":[{"id":211860,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/hyp.6130"},{"id":239232,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"20","issue":"4","noUsgsAuthors":false,"publicationDate":"2006-02-27","publicationStatus":"PW","scienceBaseUri":"505a0c7ee4b0c8380cd52b8e","contributors":{"authors":[{"text":"Dressler, K.A.","contributorId":9455,"corporation":false,"usgs":true,"family":"Dressler","given":"K.A.","email":"","affiliations":[],"preferred":false,"id":426926,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Leavesley, G.H.","contributorId":93895,"corporation":false,"usgs":true,"family":"Leavesley","given":"G.H.","email":"","affiliations":[],"preferred":false,"id":426929,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bales, R.C.","contributorId":10379,"corporation":false,"usgs":true,"family":"Bales","given":"R.C.","email":"","affiliations":[],"preferred":false,"id":426927,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Fassnacht, S.R.","contributorId":58842,"corporation":false,"usgs":true,"family":"Fassnacht","given":"S.R.","affiliations":[],"preferred":false,"id":426928,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70030379,"text":"70030379 - 2006 - The influence of fall-spawning coho salmon (Oncorhynchus kisutch) on growth and production of juvenile coho salmon rearing in beaver ponds on the Copper River Delta, Alaska","interactions":[],"lastModifiedDate":"2012-03-12T17:21:03","indexId":"70030379","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1169,"text":"Canadian Journal of Fisheries and Aquatic Sciences","active":true,"publicationSubtype":{"id":10}},"title":"The influence of fall-spawning coho salmon (Oncorhynchus kisutch) on growth and production of juvenile coho salmon rearing in beaver ponds on the Copper River Delta, Alaska","docAbstract":"This study examined the influence of fall-spawning coho salmon (Oncorhynchus kisutch) on the density, growth rate, body condition, and survival to outmigration of juvenile coho salmon on the Copper River Delta, Alaska, USA. During the fall of 1999 and 2000, fish rearing in beaver ponds that received spawning salmon were compared with fish from ponds that did not receive spawners and also with fish from ponds that were artificially enriched with salmon carcasses and eggs. The response to spawning salmon was variable. In some ponds, fall-spawning salmon increased growth rates and improved the condition of juvenile coho salmon. The enrichment with salmon carcasses and eggs significantly increased growth rates of fish in nonspawning ponds. However, there was little evidence that the short-term growth benefits observed in the fall led to greater overwinter growth or survival to outmigration when compared with fish from the nonspawning ponds. One potential reason for this result may be that nutrients from spawning salmon are widely distributed across the delta because of hydrologic connectivity and hyporheic flows. The relationship among spawning salmon, overwinter growth, and smolt production on the Copper River Delta does not appear to be limited entirely to a simple positive feedback loop. ?? 2006 NRC.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Canadian Journal of Fisheries and Aquatic Sciences","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1139/f05-268","issn":"0706652X","usgsCitation":"Lang, D., Reeves, G., Hall, J., and Wipfli, M., 2006, The influence of fall-spawning coho salmon (Oncorhynchus kisutch) on growth and production of juvenile coho salmon rearing in beaver ponds on the Copper River Delta, Alaska: Canadian Journal of Fisheries and Aquatic Sciences, v. 63, no. 4, p. 917-930, https://doi.org/10.1139/f05-268.","startPage":"917","endPage":"930","numberOfPages":"14","costCenters":[],"links":[{"id":239201,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":211831,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1139/f05-268"}],"volume":"63","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bad20e4b08c986b3239c1","contributors":{"authors":[{"text":"Lang, D.W.","contributorId":80078,"corporation":false,"usgs":true,"family":"Lang","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":426922,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reeves, G.H.","contributorId":37287,"corporation":false,"usgs":true,"family":"Reeves","given":"G.H.","email":"","affiliations":[],"preferred":false,"id":426919,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hall, J.D.","contributorId":67112,"corporation":false,"usgs":true,"family":"Hall","given":"J.D.","email":"","affiliations":[],"preferred":false,"id":426921,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Wipfli, M.S.","contributorId":51963,"corporation":false,"usgs":true,"family":"Wipfli","given":"M.S.","email":"","affiliations":[],"preferred":false,"id":426920,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70030866,"text":"70030866 - 2006 - Kinetics of sorption and abiotic oxidation of arsenic(III) by aquifer materials","interactions":[],"lastModifiedDate":"2018-10-22T10:07:42","indexId":"70030866","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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":"Kinetics of sorption and abiotic oxidation of arsenic(III) by aquifer materials","docAbstract":"The fate of arsenic in groundwater depends largely on its interaction with mineral surfaces. We investigated the kinetics of As(III) oxidation by aquifer materials collected from the USGS research site at Cape Cod, MA, USA, by conducting laboratory experiments. Five different solid samples with similar specific surface areas (0.6–0.9 m2 g−1) and reductively extractable iron contents (18–26 μmol m−2), but with varying total manganese contents (0.5–3.5 μmol m−2) were used. Both dissolved and adsorbed As(III) and As(V) concentrations were measured with time up to 250 h. The As(III) removal rate from solution increased with increasing solid manganese content, suggesting that manganese oxide is responsible for the oxidation of As(III). Under all conditions, dissolved As(V) concentrations were very low. A quantitative model was developed to simulate the extent and kinetics of arsenic transformation by aquifer materials. The model included: (1) reversible rate-limited adsorption of As(III) onto both oxidative and non-oxidative (adsorptive) sites, (2) irreversible rate-limited oxidation of As(III), and (3) equilibrium adsorption of As(V) onto adsorptive sites. Rate constants for these processes, as well as the total oxidative site densities were used as the fitting parameters. The total adsorptive site densities were estimated based on the measured specific surface area of each material. The best fit was provided by considering one fast and one slow site for each adsorptive and oxidative site. The fitting parameters were obtained using the kinetic data for the most reactive aquifer material at different initial As(III) concentrations. Using the same parameters to simulate As(III) and As(V) surface reactions, the model predictions were compared to observations for aquifer materials with different manganese contents. The model simulated the experimental data very well for all materials at all initial As(III) concentrations. The As(V) production rate was related to the concentrations of the free oxidative surface sites and dissolved As(III), as
Although surface water quality and its underlying processes vary over time scales ranging from seconds to decades, they have historically been studied at the lower (weekly to interannual) frequencies. The aim of this study was to investigate intradaily variability of three water quality parameters in a small freshwater tidal lagoon (Mildred Island, California). High frequency time series of specific conductivity, water temperature, and chlorophylla at two locations within the habitat were analyzed in conjunction with supporting hydrodynamic, meteorological, biological, and spatial mapping data. All three constituents exhibited large amplitude intradaily (e.g., semidiurnal tidal and diurnal) oscillations, and periodicity varied across constituents, space, and time. Like other tidal embayments, this habitat is influenced by several processes with distinct periodicities including physical controls, such as tides, solar radiation, and wind, and biological controls, such as photosynthesis, growth, and grazing. A scaling approach was developed to estimate individual process contributions to the observed variability. Scaling results were generally consistent with observations and together with detailed examination of time series and time derivatives, revealed specific mechanisms underlying the observed periodicities, including interactions between the tidal variability, heating, wind, and biology. The implications for monitoring were illustrated through subsampling of the data set. This exercise demonstrated how quantities needed by scientists and managers (e.g., mean or extreme concentrations) may be misrepresented by low frequency data and how short-duration high frequency measurements can aid in the design and interpretation of temporally coarser sampling programs. The dispersive export of chlorophylla from the habitat exhibited a fortnightly variability corresponding to the modulation of semidiurnal tidal currents with the diurnal cycle of phytoplankton variability, demonstrating how high frequency interactions can govern long-term trends. Process identification, as through the scaling analysis here, can help us anticipate changes in system behavior and adapt our own interactions with the system.
18O is an ideal tracer for characterizing hydrological processes because it can be reliably measured in several watershed hydrological compartments. Here, we present multiyear isotopic data, i.e. 18O variations (δ18O), for precipitation inputs, surface water and groundwater in the Shingobee River Headwaters Area (SRHA), a well-instrumented research catchment in north-central Minnesota. SRHA surface waters exhibit δ18O seasonal variations similar to those of groundwaters, and seasonal δ18O variations plotted versus time fit seasonal sine functions. These seasonal δ18O variations were interpreted to estimate surface water and groundwater mean residence times (MRTs) at sampling locations near topographically closed-basin lakes. MRT variations of about 1 to 16 years have been estimated over an area covering about 9 km2 from the basin boundary to the most downgradient well. Estimated MRT error (±0·3 to ±0·7 years) is small for short MRTs and is much larger (±10 years) for a well with an MRT (16 years) near the limit of the method. Groundwater transit time estimates based on Darcy's law, tritium content, and the seasonal δ18O amplitude approach appear to be consistent within the limits of each method. The results from this study suggest that use of the δ18O seasonal variation method to determine MRTs can help assess groundwater recharge areas in small headwaters catchments.
","language":"English","publisher":"Wiley","doi":"10.1002/hyp.5953","usgsCitation":"Reddy, M.M., Schuster, P.F., Kendall, C., and Reddy, M.B., 2006, Characterization of surface and ground water δ18O seasonal variation and its use for estimating groundwater residence times: Hydrological Processes, v. 20, no. 8, p. 1753-1772, https://doi.org/10.1002/hyp.5953.","productDescription":"20 p.","startPage":"1753","endPage":"1772","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":239168,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Minnesota","otherGeospatial":"Shingobee River Headwaters Area","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -95.152587890625,\n 46.33175800051563\n ],\n [\n -95.152587890625,\n 47.368594345213374\n ],\n [\n -93.69140625,\n 47.368594345213374\n ],\n [\n -93.69140625,\n 46.33175800051563\n ],\n [\n -95.152587890625,\n 46.33175800051563\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"20","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f4dde4b0c8380cd4bf85","contributors":{"authors":[{"text":"Reddy, Michael M. mmreddy@usgs.gov","contributorId":684,"corporation":false,"usgs":true,"family":"Reddy","given":"Michael","email":"mmreddy@usgs.gov","middleInitial":"M.","affiliations":[{"id":145,"text":"Branch of Regional Research-Central Region","active":false,"usgs":true}],"preferred":true,"id":426915,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Schuster, Paul F. 0000-0002-8314-1372 pschuste@usgs.gov","orcid":"https://orcid.org/0000-0002-8314-1372","contributorId":1360,"corporation":false,"usgs":true,"family":"Schuster","given":"Paul","email":"pschuste@usgs.gov","middleInitial":"F.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":426917,"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":426916,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Reddy, Micaela B.","contributorId":7947,"corporation":false,"usgs":true,"family":"Reddy","given":"Micaela","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":426918,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70030375,"text":"70030375 - 2006 - Occurrence of antibiotics in wastewater treatment facilities in Wisconsin, USA","interactions":[],"lastModifiedDate":"2018-10-26T08:55:32","indexId":"70030375","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3352,"text":"Science of the Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Occurrence of antibiotics in wastewater treatment facilities in Wisconsin, USA","docAbstract":"Samples from several wastewater treatment facilities in Wisconsin were screened for the presence of 21 antibiotic compounds. These facilities spanned a range of community size served (average daily flow from 0.0212 to 23.6 million gallons/day), secondary treatment processes, geographic locations across the state, and they discharged the treated effluents to both surface and ground waters (for ground water after a soil passage). A total of six antibiotic compounds were detected (1–5 compounds per site), including two sulfonamides (sulfamethazine, sulfamethoxazole), one tetracycline (tetracycline), fluoroquinolone (ciprofloxacin), macrolide (erythromycin-H2O) and trimethoprim. The frequency of detection of antibiotics was in the following order: tetracycline and trimethoprim (80%) > sulfamethoxazole (70%) > erythromycin-H2O (45%) > ciprofloxacin (40%) > sulfamethazine (10%). However, the soluble concentrations were in the parts-per-billion (ppb) range (≤ 1.3 μg/L), and importantly were unaffected by the size of the wastewater treatment facility. The concentrations detected were within an order of magnitude of those reported for similar systems in Europe and Canada: they were within a factor of two in comparison to those reported for Canada but generally lower relative to those measured in wastewater systems in Europe. Only sulfamethoxazole and tetracycline were detected in groundwater monitoring wells adjacent to the treatment systems. Future intensive wastewater monitoring programs in Wisconsin may be limited to the six antibiotic compounds detected in this study.
Ammonium (NH4+) is a major constituent of many contaminated groundwaters, but its movement through aquifers is complex and poorly documented. In this study, processes affecting NH4+ movement in a treated wastewater plume were studied by a combination of techniques including large‐scale monitoring of NH4+ distribution; isotopic analyses of coexisting aqueous NH4+, NO3−, N2, and sorbed NH4+; and in situ natural gradient 15NH4+tracer tests with numerical simulations of 15NH4+, 15NO3−, and 15N2 breakthrough data. Combined results indicate that the main mass of NH4+ was moving downgradient at a rate about 0.25 times the groundwater velocity. Retardation factors and groundwater ages indicate that much of the NH4+ in the plume was recharged early in the history of the wastewater disposal. NO3− and excess N2 gas, which were related to each other by denitrification near the plume source, were moving downgradient more rapidly and were largely unrelated to coexisting NH4+. The δ15N data indicate areas of the plume affected by nitrification (substantial isotope fractionation) and sorption (no isotope fractionation). There was no conclusive evidence for NH4+‐consuming reactions (nitrification or anammox) in the anoxic core of the plume. Nitrification occurred along the upper boundary of the plume but was limited by a low rate of transverse dispersive mixing of wastewater NH4+ and O2 from overlying uncontaminated groundwater. Without induced vertical mixing or displacement of plume water with oxic groundwater from upgradient sources, the main mass of NH4+ could reach a discharge area without substantial reaction long after the more mobile wastewater constituents are gone. Multiple approaches including in situ isotopic tracers and fractionation studies provided critical information about processes affecting NH4+ movement and N speciation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2005WR004349","usgsCitation":"Böhlke, J., Smith, R.L., and Miller, D.N., 2006, Ammonium transport and reaction in contaminated groundwater: Application of isotope tracers and isotope fractionation studies: Water Resources Research, v. 42, no. 5, W05411; 19 p., https://doi.org/10.1029/2005WR004349.","productDescription":"W05411; 19 p.","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":477593,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2005wr004349","text":"Publisher Index Page"},{"id":239546,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"42","issue":"5","noUsgsAuthors":false,"publicationDate":"2006-05-09","publicationStatus":"PW","scienceBaseUri":"5059e9c0e4b0c8380cd48425","contributors":{"authors":[{"text":"Böhlke, J.K. 0000-0001-5693-6455","orcid":"https://orcid.org/0000-0001-5693-6455","contributorId":96696,"corporation":false,"usgs":true,"family":"Böhlke","given":"J.K.","affiliations":[],"preferred":false,"id":426732,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Smith, Richard L. 0000-0002-3829-0125 rlsmith@usgs.gov","orcid":"https://orcid.org/0000-0002-3829-0125","contributorId":1592,"corporation":false,"usgs":true,"family":"Smith","given":"Richard","email":"rlsmith@usgs.gov","middleInitial":"L.","affiliations":[{"id":38175,"text":"Toxics Substances Hydrology Program","active":true,"usgs":true},{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true},{"id":36183,"text":"Hydro-Ecological Interactions Branch","active":true,"usgs":true}],"preferred":true,"id":426731,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Miller, Daniel N.","contributorId":140401,"corporation":false,"usgs":false,"family":"Miller","given":"Daniel","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":426730,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70028787,"text":"70028787 - 2006 - Applications of GIS and database technologies to manage a Karst Feature Database","interactions":[],"lastModifiedDate":"2012-03-12T17:21:00","indexId":"70028787","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2201,"text":"Journal of Cave and Karst Studies","active":true,"publicationSubtype":{"id":10}},"title":"Applications of GIS and database technologies to manage a Karst Feature Database","docAbstract":"This paper describes the management of a Karst Feature Database (KFD) in Minnesota. Two sets of applications in both GIS and Database Management System (DBMS) have been developed for the KFD of Minnesota. These applications were used to manage and to enhance the usability of the KFD. Structured Query Language (SQL) was used to manipulate transactions of the database and to facilitate the functionality of the user interfaces. The Database Administrator (DBA) authorized users with different access permissions to enhance the security of the database. Database consistency and recovery are accomplished by creating data logs and maintaining backups on a regular basis. The working database provides guidelines and management tools for future studies of karst features in Minnesota. The methodology of designing this DBMS is applicable to develop GIS-based databases to analyze and manage geomorphic and hydrologic datasets at both regional and local scales. The short-term goal of this research is to develop a regional KFD for the Upper Mississippi Valley Karst and the long-term goal is to expand this database to manage and study karst features at national and global scales.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Cave and Karst Studies","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"10906924","usgsCitation":"Gao, Y., Tipping, R., and Alexander, E., 2006, Applications of GIS and database technologies to manage a Karst Feature Database: Journal of Cave and Karst Studies, v. 68, no. 3, p. 144-152.","startPage":"144","endPage":"152","numberOfPages":"9","costCenters":[],"links":[{"id":236583,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"68","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ecc3e4b0c8380cd49486","contributors":{"authors":[{"text":"Gao, Y.","contributorId":82437,"corporation":false,"usgs":true,"family":"Gao","given":"Y.","email":"","affiliations":[],"preferred":false,"id":419751,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tipping, R.G.","contributorId":67272,"corporation":false,"usgs":true,"family":"Tipping","given":"R.G.","email":"","affiliations":[],"preferred":false,"id":419750,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Alexander, E.C. Jr.","contributorId":94062,"corporation":false,"usgs":true,"family":"Alexander","given":"E.C.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":419752,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70030904,"text":"70030904 - 2006 - Trophic transfer of trace metals: Subcellular compartmentalization in a polychaete and assimilation by a decapod crustacean","interactions":[],"lastModifiedDate":"2018-10-29T09:02:07","indexId":"70030904","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2663,"text":"Marine Ecology Progress Series","active":true,"publicationSubtype":{"id":10}},"title":"Trophic transfer of trace metals: Subcellular compartmentalization in a polychaete and assimilation by a decapod crustacean","docAbstract":"The chemical form of accumulated trace metal in prey is important in controlling the bioavailability of dietary metal to a predator. This study investigated the trophic transfer of radiolabelled Ag, Cd and Zn from the polychaete worm Nereis diversicolor to the decapod crustacean Palaemonetes varians. We used 2 populations of worms with different proportions of accumulated metals in different subcellular fractions as prey, and loaded the worms with radiolabelled metals either from sediment or from solution. Accumulated radiolabelled metals were fractionated into 5 components:metal-rich granules (MRG), cellular debris, organelles, metallothionein-like proteins (MTLP), and other (heat-sensitive) proteins (HSP). Assimilation efficiencies (AE) of the metals by P. varians were measured from the 4 categories of prey (i.e. 2 populations, radiolabelled from sediment or solution). There were significant differences for each metal between the AEs from the different prey categories, confirming that origin of prey and route of uptake of accumulated trace metal will cause intraspecific differences in subsequent metal assimilation. Correlations were sought between AEs and selected fractions or combinations of fractions of metals in the prey-MRG, Trophically Available Metal (TAM = MTLP + HSP + organelles) and total protein (MTLP + HSP). TAM explained 28% of the variance in AEs for Ag, but no consistent relationships emerged between AEs and TAM or total protein when the metals were considered separately. AEs did, however, show significant positive regressions with both TAM and total protein when the 3 metals were considered together, explaining only about 21% of the variance in each case. A significant negative relationship was observed between MRG and AE for all metals combined. The predator (P. varians) can assimilate dietary metal from a range of the fractions binding metals in the prey (N. diversicolor), with different assimilation efficiencies summated across these fractions. TAM and/or total protein may represent an approximate minimum for trophic availability but neither of these alone is a fully accurate predictor.
","language":"English","publisher":"Int Res","doi":"10.3354/meps308091","issn":"01718630","usgsCitation":"Rainbow, P., Poirier, L., Smith, B.D., Brix, K., and Luoma, S., 2006, Trophic transfer of trace metals: Subcellular compartmentalization in a polychaete and assimilation by a decapod crustacean: Marine Ecology Progress Series, v. 308, p. 91-100, https://doi.org/10.3354/meps308091.","productDescription":"10 p.","startPage":"91","endPage":"100","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":477706,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.3354/meps308091","text":"Publisher Index Page"},{"id":238769,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"308","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb890e4b08c986b327923","contributors":{"authors":[{"text":"Rainbow, P.S.","contributorId":46753,"corporation":false,"usgs":true,"family":"Rainbow","given":"P.S.","affiliations":[],"preferred":false,"id":429151,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Poirier, L.","contributorId":28053,"corporation":false,"usgs":true,"family":"Poirier","given":"L.","email":"","affiliations":[],"preferred":false,"id":429150,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Smith, B. D.","contributorId":71123,"corporation":false,"usgs":true,"family":"Smith","given":"B.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":429152,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Brix, K.V.","contributorId":99761,"corporation":false,"usgs":true,"family":"Brix","given":"K.V.","email":"","affiliations":[],"preferred":false,"id":429154,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":429153,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70030911,"text":"70030911 - 2006 - Chemical loading into surface water along a hydrological, biogeochemical, and land use gradient: A holistic watershed approach","interactions":[],"lastModifiedDate":"2021-05-27T14:44:49.143923","indexId":"70030911","displayToPublicDate":"2006-01-01T00:00:00","publicationYear":"2006","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":"Chemical loading into surface water along a hydrological, biogeochemical, and land use gradient: A holistic watershed approach","docAbstract":"Identifying the sources and impacts of organic and inorganic contaminants at the watershed scale is a complex challenge because of the multitude of processes occurring in time and space. Investigation of geochemical transformations requires a systematic evaluation of hydrologic, landscape, and anthropogenic factors. The 1160 km2 Boulder Creek Watershed in the Colorado Front Range encompasses a gradient of geology, ecotypes, climate, and urbanization. Streamflow originates primarily as snowmelt and shows substantial annual variation. Water samples were collected along a 70-km transect during spring-runoff and base-flow conditions, and analyzed for major elements, trace elements, bulk organics, organic wastewater contaminants (OWCs), and pesticides. Major-element and trace-element concentrations were low in the headwaters, increased through the urban corridor, and had a step increase downstream from the first major wastewater treatment plant (WWTP). Boron, gadolinium, and lithium were useful inorganic tracers of anthropogenic inputs. Effluent from the WWTP accounted for as much as 75% of the flow in Boulder Creek and was the largest chemical input. Under both hydrological conditions, OWCs and pesticides were detected in Boulder Creek downstream from the WWTP outfall as well as in the headwater region, and loads of anthropogenic-derived contaminants increased as basin population density increased. This report documents a suite of potential endocrine-disrupting chemicals in a reach of stream with native fish populations showing indication of endocrine disruption.
Nitrification was measured within a sand and gravel aquifer on Cape Cod, MA, using a series of single-well injection tests. The aquifer contained a wastewater-derived contaminant plume, the core of which was anoxic and contained ammonium. The study was conducted near the downgradient end of the ammonium zone, which was characterized by inversely trending vertical gradients of oxygen (270 to 0 μM) and ammonium (19 to 625 μM) and appeared to be a potentially active zone for nitrification. The tests were conducted by injecting a tracer solution (ambient ground water + added constituents) into selected locations within the gradients using multilevel samplers. After injection, the tracers moved by natural ground water flow and were sampled with time from the injection port. Rates of nitrification were determined from changes in nitrate and nitrite concentration relative to bromide. Initial tests were conducted with 15N-enriched ammonium; subsequent tests examined the effect of adding ammonium, nitrite, or oxygen above background concentrations and of adding difluoromethane, a nitrification inhibitor. In situ net nitrate production exceeded net nitrite production by 3- to 6- fold and production rates of both decreased in the presence of difluoromethane. Nitrification rates were 0.02–0.28 μmol (L aquifer)−1 h−1 with in situ oxygen concentrations and up to 0.81 μmol (L aquifer)−1 h−1 with non-limiting substrate concentrations. Geochemical considerations indicate that the rates derived from single-well injection tests yielded overestimates of in situ rates, possibly because the injections promoted small-scale mixing within a transport-limited reaction zone. Nonetheless, these tests were useful for characterizing ground water nitrification in situ and for comparing potential rates of activity when the tracer cloud included non-limiting ammonium and oxygen concentrations.
","language":"English","publisher":"Springer","doi":"10.1007/s00248-004-0159-7","issn":"00953628","usgsCitation":"Smith, R.L., Baumgartner, L., Miller, D., Repert, D., and Böhlke, J., 2006, Assessment of nitrification potential in ground water using short term, single-well injection experiments: Microbial Ecology, v. 51, no. 1, p. 22-35, https://doi.org/10.1007/s00248-004-0159-7.","productDescription":"14 p.","startPage":"22","endPage":"35","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":238932,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":211615,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s00248-004-0159-7"}],"volume":"51","issue":"1","noUsgsAuthors":false,"publicationDate":"2006-01-01","publicationStatus":"PW","scienceBaseUri":"5059ee43e4b0c8380cd49c71","contributors":{"authors":[{"text":"Smith, R. L.","contributorId":93904,"corporation":false,"usgs":true,"family":"Smith","given":"R.","email":"","middleInitial":"L.","affiliations":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"preferred":false,"id":429209,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Baumgartner, L.K.","contributorId":93695,"corporation":false,"usgs":true,"family":"Baumgartner","given":"L.K.","email":"","affiliations":[],"preferred":false,"id":429208,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Miller, D.N.","contributorId":36324,"corporation":false,"usgs":true,"family":"Miller","given":"D.N.","email":"","affiliations":[],"preferred":false,"id":429206,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Repert, D.A.","contributorId":78506,"corporation":false,"usgs":true,"family":"Repert","given":"D.A.","affiliations":[],"preferred":false,"id":429207,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Böhlke, J.K. 0000-0001-5693-6455","orcid":"https://orcid.org/0000-0001-5693-6455","contributorId":96696,"corporation":false,"usgs":true,"family":"Böhlke","given":"J.K.","affiliations":[],"preferred":false,"id":429210,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ]}