This chapter aims to describe advances in analytical instrumentation and methods for the analyses of herbicides and their degradation products and to assess their impact on major findings of broad surveys of herbicides in water conducted by the U.S. Geological Survey(USGS) over the last two decades. Standards for water purity have been set and continually revised by governments as new contaminants that may impact human health are identified. These water-purity standards have brought continued improvement in water quality of existing water sources by reducing the amount of pollution in drinking water, treating wastewater, diverting wastewater discharge from drinking-water supplies, implementing new filtration practices, and other innovative techniques. It is vital that state-of-the-art instrumentation for analyzing organic contaminants continually be introduced into the marketplace the advancement of analytical instrumentation has given scientists the capability to continually broaden their studies of the fate of herbicides and their degradation products over the last two decades. Studies by many scientists have continually expanded the knowledge of the occurrence, persistence, and transport of herbicides and their degradation products in the hydrologic environment.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Handbook of water purity and quality","language":"English","publisher":"Academic Press","publisherLocation":"Amsterdam","doi":"10.1016/B978-0-12-374192-9.00013-3","usgsCitation":"Meyer, M.T., and Scribner, E.A., 2009, The Evolution of analytical technology and its impact on water-quality studies for selected herbicides and their degradation products in water, chap. 13 of Handbook of water purity and quality, p. 289-313, https://doi.org/10.1016/B978-0-12-374192-9.00013-3.","productDescription":"25 p.","startPage":"289","endPage":"313","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":356790,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5b98ba2ee4b0702d0e845330","contributors":{"editors":[{"text":"Ahuja, Satinder","contributorId":59343,"corporation":false,"usgs":true,"family":"Ahuja","given":"Satinder","affiliations":[],"preferred":false,"id":743556,"contributorType":{"id":2,"text":"Editors"},"rank":1}],"authors":[{"text":"Meyer, Michael T. 0000-0001-6006-7985 mmeyer@usgs.gov","orcid":"https://orcid.org/0000-0001-6006-7985","contributorId":866,"corporation":false,"usgs":true,"family":"Meyer","given":"Michael","email":"mmeyer@usgs.gov","middleInitial":"T.","affiliations":[{"id":353,"text":"Kansas Water Science Center","active":false,"usgs":true}],"preferred":true,"id":743554,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Scribner, Elisabeth A.","contributorId":80265,"corporation":false,"usgs":true,"family":"Scribner","given":"Elisabeth","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":743555,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70230294,"text":"70230294 - 2009 - Approaches to modeling weathered regolith","interactions":[],"lastModifiedDate":"2022-04-06T16:25:16.225578","indexId":"70230294","displayToPublicDate":"2009-01-01T10:43:06","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3281,"text":"Reviews in Mineralogy and Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Approaches to modeling weathered regolith","docAbstract":"Sustainable soils are a requirement for maintaining human civilizations (Carter and Dale 1974; Lal 1989). However, as the “most complicated biomaterial on the planet” (Young and Crawford 2004), soils represent one of the most difficult systems to understand and model with respect to chemical, physical, and biological coupling over time (Fig. 1).
Despite the complexity of these interactions, certain patterns in soil properties and development are universally observed and have been used in soil science as a means for classification. Elemental, mineralogical, or isotopic concentrations in soils plotted versus depth beneath the land surface comprise such patterns. Soil depth profiles are often reported for solid soil materials, and, less frequently, for solutes in soil pore waters. These profiles cross a large range in spatial scales that traditionally have been studied by different disciplines. For example, shallow, biologically active horizons are commonly defined as the soil zone in agronomic studies whereas the mobile layer of the regolith is referred to as soil in geomorphological studies. In contrast, many geochemical studies target chemical weathering to tens or even hundreds of meters in depth, sometimes extending the definition of “soils” to include the entire regolith down to parent bedrock or alluvium.
Soil profiles also exhibit a large range in temporal scales (Amundson 2004; Brantley 2008b). Solid-state profiles document chemical and mineralogical changes integrated over the time scales of evolution of regolith from protolith. This “geologic time” can vary from tens to hundreds of years for weathered material developed on moraines deposited by active glaciers (Anderson et al. 1997), to millions or possibly hundreds of millions of years of regolith evolution as documented in laterites and bauxites on stable cratons (Nahon 1986). In contrast, solute profiles reflect much shorter time scales corresponding to the residence time of the soil water which commonly ranges from days to decades (Stonestrom et al. 1998). Factors impacting soil minerals can therefore be related to geologically old processes while those impacting pore waters are related to contemporary processes.
We first discuss a geochemical frame work for modeling soil profiles, including a simple scheme that depends on the extent of enrichment or depletion. Such profiles are comprised of reaction fronts affected by chemical, hydrologic, geologic and biologic processes that control soil evolution. We then present a hierarchy of models that have been used to interpret both solid state and solute compositions in regolith. The more simple approaches to model depletion in soils, using analytical models, are first described. The most elementary of these is a linear model that calculates rate constants from the slopes of either solid or solute weathering gradients: these rate constants represent lumped parameters that describe weathering in terms of an integrated reaction rate. Two other analytical models are then presented that have been used to fit solid state elemental profiles with exponential and sigmoidal functions. All of these analytical approaches are derived for models of soils as containing a limited number of components, phases, and species.
At a more complex level, numerical models are then presented to elucidate how kinetic and transport parameters as well as chemical, hydrologic, and physical soil data can be incorporated. We consider two forms of these models, first relatively simple spreadsheet calculators and then more sophisticated multi-component, multi-phase reactive-transport numerical codes. Our treatment of reactive transport modeling is relatively cursory, in recognition of the treatment in the chapter by Steefel and Maher (2009, this volume). Because these models incorporate more phases, components, and species than the other approaches and explicitly model the more fundamental reaction mechanisms involved, they generally have a greater need for parameterization. In our conclusion section, we discuss how this hierarchy of approaches can yield generalizations about soils that are often complementary.
Environmental radionuclides—in combination with stable isotopes, geochemistry, and other hydrological techniques—provide a powerful tool, often indispensable, for studying the cycling of water in continental hydrological systems. The use of environmental radionuclides in surface water studies is reviewed in the chapter. The chapter also briefly discusses groundwater and geothermal water taking into consideration the fact that most applications in groundwater and geothermal water studies require the combined use of radioactive and stable isotopes. There are several sources of radionuclides in the environment, and the sources control the ways in which isotopes can be applied to hydrologic systems. Another group of radionuclides that can be utilized are those produced by cosmic-ray spallationin the atmosphere or near-surface lithosphere. Many of these nuclides, such as carbon-14 (14C) and tritium (3H), are also produced by nuclear weapons testing, and it is necessary to separate the two source functions when using them.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Radioactivity in the environment","language":"English","publisher":"Elsevier","doi":"10.1016/S1569-4860(09)01605-2","usgsCitation":"Michel, R.L., 2009, Radionuclides as tracers and timers in surface and groundwater, chap. 5 of Radioactivity in the environment, v. 16, p. 139-230, https://doi.org/10.1016/S1569-4860(09)01605-2.","productDescription":"92 p.","startPage":"139","endPage":"230","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":357044,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"16","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5b98ba2ee4b0702d0e845332","contributors":{"authors":[{"text":"Michel, Robert L. rlmichel@usgs.gov","contributorId":823,"corporation":false,"usgs":true,"family":"Michel","given":"Robert","email":"rlmichel@usgs.gov","middleInitial":"L.","affiliations":[{"id":148,"text":"Branch of Regional Research-Western Region","active":false,"usgs":true}],"preferred":true,"id":744111,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70200362,"text":"70200362 - 2009 - Investigation of river eutrophication as part of a low dissolved oxygen total maximum daily load implementation","interactions":[],"lastModifiedDate":"2018-10-15T10:36:47","indexId":"70200362","displayToPublicDate":"2009-01-01T10:32:05","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3724,"text":"Water Science and Technology","active":true,"publicationSubtype":{"id":10}},"title":"Investigation of river eutrophication as part of a low dissolved oxygen total maximum daily load implementation","docAbstract":"In the United States, environmentally impaired rivers are subject to regulation under total maximum daily load (TMDL) regulations that specify watershed wide water quality standards. In California, the setting of TMDL standards is accompanied by the development of scientific and management plans directed at achieving specific water quality objectives. The San Joaquin River (SJR) in the Central Valley of California now has a TMDL for dissolved oxygen (DO). Low DO conditions in the SJR are caused in part by excessive phytoplankton growth (eutrophication) in the shallow, upstream portion of the river that create oxygen demand in the deeper estuary. This paper reports on scientific studies that were conducted to develop a mass balance on nutrients and phytoplankton in the SJR. A mass balance model was developed using WARMF, a model specifically designed for use in TMDL management applications. It was demonstrated that phytoplankton biomass accumulates rapidly in a 88 km reach where plankton from small, slow moving tributaries are diluted and combined with fresh nutrient inputs in faster moving water. The SJR-WARMF model was demonstrated to accurately predict phytoplankton growth in the SJR. Model results suggest that modest reductions in nutrients alone will not limit algal biomass accumulation, but that combined strategies of nutrient reduction and algal control in tributaries may have benefit. The SJR-WARMF model provides stakeholders a practical, scientific tool for setting remediation priorities on a watershed scale.
","language":"English","publisher":"IWA","doi":"10.2166/wst.2009.739","usgsCitation":"Stringfellow, W., Litton, G., Borglin, S., Hanlon, J.R., Chen, C., Graham, J., Burks, R., Dahlgren, R., Kendall, C., Brown, R., and Quinn, N., 2009, Investigation of river eutrophication as part of a low dissolved oxygen total maximum daily load implementation: Water Science and Technology, v. 59, no. 1, p. 9-14, https://doi.org/10.2166/wst.2009.739.","productDescription":"6 p.","startPage":"9","endPage":"14","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":487896,"rank":0,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://scholarlycommons.pacific.edu/soecs-facarticles/192","text":"External Repository"},{"id":358367,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"59","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5c10cd71e4b034bf6a7f8b59","contributors":{"authors":[{"text":"Stringfellow, W.","contributorId":41709,"corporation":false,"usgs":true,"family":"Stringfellow","given":"W.","affiliations":[],"preferred":false,"id":748499,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Litton, Gary","contributorId":209646,"corporation":false,"usgs":false,"family":"Litton","given":"Gary","email":"","affiliations":[],"preferred":false,"id":748500,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Borglin, Sharon","contributorId":175251,"corporation":false,"usgs":false,"family":"Borglin","given":"Sharon","email":"","affiliations":[],"preferred":false,"id":748501,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hanlon, James R. jrhanlon@usgs.gov","contributorId":4598,"corporation":false,"usgs":true,"family":"Hanlon","given":"James","email":"jrhanlon@usgs.gov","middleInitial":"R.","affiliations":[],"preferred":true,"id":748502,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Chen, C.","contributorId":98490,"corporation":false,"usgs":true,"family":"Chen","given":"C.","email":"","affiliations":[],"preferred":false,"id":748503,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Graham, J.","contributorId":73826,"corporation":false,"usgs":true,"family":"Graham","given":"J.","email":"","affiliations":[],"preferred":false,"id":748504,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Burks, Remie","contributorId":209647,"corporation":false,"usgs":false,"family":"Burks","given":"Remie","email":"","affiliations":[],"preferred":false,"id":748505,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Dahlgren, Randy A.","contributorId":48630,"corporation":false,"usgs":true,"family":"Dahlgren","given":"Randy A.","affiliations":[],"preferred":false,"id":748506,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"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":748507,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Brown, R.","contributorId":101419,"corporation":false,"usgs":true,"family":"Brown","given":"R.","affiliations":[],"preferred":false,"id":748508,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Quinn, Nigel","contributorId":58169,"corporation":false,"usgs":true,"family":"Quinn","given":"Nigel","affiliations":[],"preferred":false,"id":748509,"contributorType":{"id":1,"text":"Authors"},"rank":11}]}} ,{"id":70200359,"text":"70200359 - 2009 - Ingredients in sustainably managing water in semi-arid environments","interactions":[],"lastModifiedDate":"2018-10-15T09:49:35","indexId":"70200359","displayToPublicDate":"2009-01-01T09:48:50","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1563,"text":"Environmental Science and Policy","active":true,"publicationSubtype":{"id":10}},"title":"Ingredients in sustainably managing water in semi-arid environments","docAbstract":"The lessons learned from CALFED indicate that ingredients important in the long-term resolution of water management issues may not result in short-term “solutions”. The value of this special issue lies in its identification of ingredients that stimulate re-framing of issues, adapting to new knowledge and innovative decisions. But sustainable water management also requires the political patience to sustain those processes as a means of perpetuating the long-term decision-making necessary to anticipate and/or respond to an ever-changing environment.
Livestock grazing is a common land use across the western United States, but concerns have been raised regarding its potential to affect amphibian populations. We studied the short-term effects of full and partial livestock grazing exclosures on Rana luteiventris (Columbia Spotted Frog) populations using a controlled manipulative field experiment with pre- and posttreatment data (2002–2006). Despite a significant increase in vegetation height within grazing exclosures, we did not find treatment effects for egg mass counts, larval survival, or size at metamorphosis 1–2 years following grazing exclosure installation. Water samples taken in late summer showed concentrations of nitrite, nitrate, ammonia, and orthophosphate that were low or near detection limits across all ponds and years. The results of this experiment do not support a hypothesis that limiting cattle access to breeding ponds will help conserve R. luteiventris populations in our study area. Further research is needed to evaluate regional variation and long-term effects of grazing exclosures on R. luteiventrispopulations.
","language":"English","publisher":"The Society for the Study of Amphibians and Reptiles","doi":"10.1670/08-016R2.1","usgsCitation":"Adams, M.J., Pearl, C., McCreary, B., Galvan, S., Wessell, S.J., Wente, W., Anderson, C.W., and Kuehl, A.B., 2009, Short-term effect of cattle exclosures on Columbia Spotted Frog (Rana luteiventris) populations and habitat in northeastern Oregon: Journal of Herpetology, v. 43, no. 1, p. 132-138, https://doi.org/10.1670/08-016R2.1.","productDescription":"7 p.","startPage":"132","endPage":"138","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":358234,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"43","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5c10cd72e4b034bf6a7f8b5d","contributors":{"authors":[{"text":"Adams, M. J. 0000-0001-8844-042X mjadams@usgs.gov","orcid":"https://orcid.org/0000-0001-8844-042X","contributorId":3133,"corporation":false,"usgs":false,"family":"Adams","given":"M.","email":"mjadams@usgs.gov","middleInitial":"J.","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true},{"id":200,"text":"Coop Res Unit Seattle","active":true,"usgs":true},{"id":289,"text":"Forest and Rangeland Ecosys Science Center","active":true,"usgs":true}],"preferred":true,"id":747672,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Pearl, Christopher 0000-0003-2943-7321 christopher_pearl@usgs.gov","orcid":"https://orcid.org/0000-0003-2943-7321","contributorId":172669,"corporation":false,"usgs":true,"family":"Pearl","given":"Christopher","email":"christopher_pearl@usgs.gov","affiliations":[{"id":289,"text":"Forest and Rangeland Ecosys Science Center","active":true,"usgs":true},{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"preferred":true,"id":747673,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McCreary, Brome 0000-0002-0313-7796 brome_mccreary@usgs.gov","orcid":"https://orcid.org/0000-0002-0313-7796","contributorId":3130,"corporation":false,"usgs":true,"family":"McCreary","given":"Brome","email":"brome_mccreary@usgs.gov","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true},{"id":289,"text":"Forest and Rangeland Ecosys Science Center","active":true,"usgs":true}],"preferred":true,"id":747674,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Galvan, Stephanie 0000-0002-9864-3674 stephanie_galvan@usgs.gov","orcid":"https://orcid.org/0000-0002-9864-3674","contributorId":3135,"corporation":false,"usgs":true,"family":"Galvan","given":"Stephanie","email":"stephanie_galvan@usgs.gov","affiliations":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true},{"id":289,"text":"Forest and Rangeland Ecosys Science Center","active":true,"usgs":true}],"preferred":true,"id":747675,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Wessell, Stephanie J.","contributorId":208552,"corporation":false,"usgs":false,"family":"Wessell","given":"Stephanie","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":747676,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Wente, Wendy","contributorId":60497,"corporation":false,"usgs":true,"family":"Wente","given":"Wendy","email":"","affiliations":[],"preferred":false,"id":747677,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Anderson, Chauncey W. 0000-0002-1016-3781 chauncey@usgs.gov","orcid":"https://orcid.org/0000-0002-1016-3781","contributorId":140160,"corporation":false,"usgs":true,"family":"Anderson","given":"Chauncey","email":"chauncey@usgs.gov","middleInitial":"W.","affiliations":[{"id":518,"text":"Oregon Water Science Center","active":true,"usgs":true}],"preferred":true,"id":747678,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Kuehl, Allison B.","contributorId":208553,"corporation":false,"usgs":false,"family":"Kuehl","given":"Allison","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":747679,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70199993,"text":"70199993 - 2009 - Dietary segregation of pelagic and littoral fish assemblages in a highly modified tidal freshwater estuary","interactions":[],"lastModifiedDate":"2018-10-10T09:42:28","indexId":"70199993","displayToPublicDate":"2009-01-01T09:41:16","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2680,"text":"Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science","active":true,"publicationSubtype":{"id":10}},"title":"Dietary segregation of pelagic and littoral fish assemblages in a highly modified tidal freshwater estuary","docAbstract":"Estuarine food webs are highly variable and complex, making identification of their trophic pathways difficult. Energy for the food web of the San Francisco Estuary is thought to be based largely on in situ phytoplankton production, but little attention has been paid to littoral habitats, where other energy sources may be important. We analyzed the stomach contents of over 960 juvenile fishes and the stable carbon and nitrogen isotope ratios of these fishes and their potential food resources in pelagic and littoral habitats from the tidal freshwater area of the estuary. The mixing model IsoSource was used to examine energy sources important to consumers. Our results show evidence of two predominant food web pathways. Pelagic fishes and some littoral fishes showed strong dependence on a zooplankton–phytoplankton trophic pathway. However, the majority of fishes in littoral habitats had diets and carbon isotope ratios consistent with energy arising from submerged aquatic vegetation and epiphytic macroalgae. IsoSource revealed that the overall majority of nutrition of littoral fishes originated from consumption of grazer amphipods. Examining both stable isotopes and stomach contents allowed us to identify a food web with contributions to resident fishes that had been previously underestimated in the estuary. This study provides insight to how estuarine food webs have changed over the last few decades and highlights why the functions of habitats must be understood for effective restoration planning.
With phase inversion, one can estimate subsurface velocities using the phases of first-arriving waves, which are the frequency-domain equivalents of the traveltimes. Phase inversion is modified to make it suitable for processing traveltimes from near-surface refraction surveys. The modifications include parameterizing the model, correcting the observed phases, and selecting the complex frequency. This modified phase inversion is compared to traveltime tomography. For two comparisons using computer-simulated traveltimes, the difference between the estimated and correct models, the residual mean, and the residual standard deviation are smaller for the phase inversion than they are for the traveltime tomography. For a comparison using field data from an S-wave refraction survey, both methods estimate models that are consistent with the known geology. Nonetheless, the phase-inversion model includes small-scale features in the bedrock that are geologically plausible; the residual mean and the residual standard deviation are smaller for the phase inversion than they are for the traveltime tomography.
","language":"English","publisher":"GeoScienceWorld","doi":"10.1190/1.3196857","usgsCitation":"Ellefsen, K.J., 2009, A comparison of phase inversion and traveltime tomography for processing near-surface refraction traveltimes: Geophysical Journal, v. 74, no. 6, p. WCB11-WCB24, https://doi.org/10.1190/1.3196857.","productDescription":"14 p.","startPage":"WCB11","endPage":"WCB24","costCenters":[{"id":211,"text":"Crustal Geophysics and Geochemistry Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":358231,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"74","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5c10cd72e4b034bf6a7f8b61","contributors":{"authors":[{"text":"Ellefsen, Karl J. 0000-0003-3075-4703 ellefsen@usgs.gov","orcid":"https://orcid.org/0000-0003-3075-4703","contributorId":789,"corporation":false,"usgs":true,"family":"Ellefsen","given":"Karl","email":"ellefsen@usgs.gov","middleInitial":"J.","affiliations":[{"id":82803,"text":"Geology, Geophysics, and Geochemistry Science Center","active":true,"usgs":false}],"preferred":true,"id":747656,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70199984,"text":"70199984 - 2009 - What does \"water quality\" mean?","interactions":[],"lastModifiedDate":"2018-10-10T08:39:13","indexId":"70199984","displayToPublicDate":"2009-01-01T08:30:48","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"title":"What does \"water quality\" mean?","docAbstract":"No abstract available.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.2009.00569.x","usgsCitation":"Chapelle, F.H., Bradley, P.M., McMahon, P.B., and Lindsey, B.D., 2009, What does \"water quality\" mean?: Groundwater, v. 47, no. 6, p. 752-754, https://doi.org/10.1111/j.1745-6584.2009.00569.x.","productDescription":"3 p.","startPage":"752","endPage":"754","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":358223,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"47","issue":"6","noUsgsAuthors":false,"publicationDate":"2009-10-16","publicationStatus":"PW","scienceBaseUri":"5c10cd72e4b034bf6a7f8b69","contributors":{"authors":[{"text":"Chapelle, Francis H. chapelle@usgs.gov","contributorId":1350,"corporation":false,"usgs":true,"family":"Chapelle","given":"Francis","email":"chapelle@usgs.gov","middleInitial":"H.","affiliations":[{"id":13634,"text":"South Atlantic Water Science Center","active":true,"usgs":true},{"id":559,"text":"South Carolina Water Science Center","active":true,"usgs":true}],"preferred":true,"id":747621,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bradley, Paul M. 0000-0001-7522-8606 pbradley@usgs.gov","orcid":"https://orcid.org/0000-0001-7522-8606","contributorId":204639,"corporation":false,"usgs":true,"family":"Bradley","given":"Paul","email":"pbradley@usgs.gov","middleInitial":"M.","affiliations":[{"id":13634,"text":"South Atlantic Water Science Center","active":true,"usgs":true}],"preferred":true,"id":747622,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McMahon, Peter B. 0000-0001-7452-2379 pmcmahon@usgs.gov","orcid":"https://orcid.org/0000-0001-7452-2379","contributorId":724,"corporation":false,"usgs":true,"family":"McMahon","given":"Peter","email":"pmcmahon@usgs.gov","middleInitial":"B.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":747623,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Lindsey, Bruce D. 0000-0002-7180-4319 blindsey@usgs.gov","orcid":"https://orcid.org/0000-0002-7180-4319","contributorId":206667,"corporation":false,"usgs":true,"family":"Lindsey","given":"Bruce","email":"blindsey@usgs.gov","middleInitial":"D.","affiliations":[{"id":451,"text":"National Water Quality Assessment Program","active":true,"usgs":true}],"preferred":true,"id":747624,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70199982,"text":"70199982 - 2009 - Dual nitrate isotopes in dry deposition: Utility for partitioning NOx source contributions to landscape nitrogen deposition","interactions":[],"lastModifiedDate":"2018-10-10T08:27:23","indexId":"70199982","displayToPublicDate":"2009-01-01T08:22:07","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2320,"text":"Journal of Geophysical Research: Biogeosciences","active":true,"publicationSubtype":{"id":10}},"title":"Dual nitrate isotopes in dry deposition: Utility for partitioning NOx source contributions to landscape nitrogen deposition","docAbstract":"Dry deposition is a major component of total atmospheric nitrogen deposition and thus an important source of bioavailable nitrogen to ecosystems. However, relative to wet deposition, less is known regarding the sources and spatial variability of dry deposition. This is in part due to difficulty in measuring dry deposition and associated deposition velocities. Passive sampling techniques offer potential for improving our understanding of the spatial distribution and sources of gaseous and aerosol N species, referred to here as dry deposition. We report dual nitrate isotopic composition (δ15N and δ18O) in actively collected dry and wet deposition across the high‐deposition region of Ohio, New York, and Pennsylvania. We also present results from initial tests to examine the efficacy of using passive nitric acid collectors as a collection medium for isotopic analysis at a site in New York. Isotopic values in actively collected dry deposition, including particulate nitrate and gaseous nitric acid, are compared with those in wet nitrate deposition and surrounding NOx emission sources. δ15N values in dry and wet fractions are highest at the westernmost sites and lowest at the easternmost sites, and stationary source NOx emissions (e.g., power plants and incinerators) appear to be the primary control on δ15N spatial variability. In contrast, δ18O values show a less consistent spatial pattern in dry deposition. Both δ15N and δ18O show strong seasonality, with higher values in winter than summer. Seasonal variations in stationary source NOxemissions appear to be the most likely explanation for seasonal variations in δ15N, whereas seasonal variations in air temperature and solar radiation indicate variable chemical oxidation pathways control δ18O patterns. Additionally, we demonstrate the utility of passive samplers for collecting the nitric acid (HNO3) component of dry deposition suitable for isotopic analysis. We observe slight differences in δ15N‐HNO3values between simultaneous samples collected actively and passively (0.6‰). However, we observe a larger offset in δ18O values between actively and passively collected samples; the causes for this offset warrant further investigation. Nonetheless, passive sample collection represents a significant cost savings over active sampling techniques and could allow a more extensive understanding of patterns of dry deposition and associated insights to nitrogen sources across landscapes.
","language":"English","publisher":"AGU","doi":"10.1029/2008JG000889","usgsCitation":"Elliott, E., Kendall, C., Boyer, E., Burns, D.A., Lear, G., Golden, H., Harlin, K., Bytnerowicz, A., Butler, T., and Glatz, R., 2009, Dual nitrate isotopes in dry deposition: Utility for partitioning NOx source contributions to landscape nitrogen deposition: Journal of Geophysical Research: Biogeosciences, v. 114, no. 4, G04020, https://doi.org/10.1029/2008JG000889.","productDescription":"G04020","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":358222,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"114","issue":"4","noUsgsAuthors":false,"publicationDate":"2009-12-11","publicationStatus":"PW","scienceBaseUri":"5c10cd73e4b034bf6a7f8b6b","contributors":{"authors":[{"text":"Elliott, E.M.","contributorId":78064,"corporation":false,"usgs":true,"family":"Elliott","given":"E.M.","email":"","affiliations":[],"preferred":false,"id":747611,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"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":747612,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Boyer, E.W.","contributorId":56358,"corporation":false,"usgs":false,"family":"Boyer","given":"E.W.","email":"","affiliations":[{"id":6738,"text":"The Pennsylvania State University","active":true,"usgs":false}],"preferred":false,"id":747613,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Burns, Douglas A. 0000-0001-6516-2869 daburns@usgs.gov","orcid":"https://orcid.org/0000-0001-6516-2869","contributorId":1237,"corporation":false,"usgs":true,"family":"Burns","given":"Douglas","email":"daburns@usgs.gov","middleInitial":"A.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":747614,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Lear, Gary","contributorId":37362,"corporation":false,"usgs":true,"family":"Lear","given":"Gary","email":"","affiliations":[],"preferred":false,"id":747615,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Golden, H.E.","contributorId":204050,"corporation":false,"usgs":false,"family":"Golden","given":"H.E.","email":"","affiliations":[{"id":36810,"text":"U.S. EPA Office of Research and Development, National Exposure Research Laboratory","active":true,"usgs":false}],"preferred":false,"id":747616,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Harlin, K.","contributorId":107498,"corporation":false,"usgs":true,"family":"Harlin","given":"K.","email":"","affiliations":[],"preferred":false,"id":747617,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Bytnerowicz, A.","contributorId":30027,"corporation":false,"usgs":true,"family":"Bytnerowicz","given":"A.","email":"","affiliations":[],"preferred":false,"id":747618,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Butler, T.J.","contributorId":86973,"corporation":false,"usgs":true,"family":"Butler","given":"T.J.","email":"","affiliations":[],"preferred":false,"id":747619,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Glatz, R.","contributorId":208542,"corporation":false,"usgs":false,"family":"Glatz","given":"R.","email":"","affiliations":[],"preferred":false,"id":747620,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}} ,{"id":70199980,"text":"70199980 - 2009 - Response to \"comment on 'bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure'\"","interactions":[],"lastModifiedDate":"2018-10-10T07:52:50","indexId":"70199980","displayToPublicDate":"2009-01-01T07:47:32","publicationYear":"2009","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":"Response to \"comment on 'bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure'\"","docAbstract":"No abstract available.
","language":"English","publisher":"ACS","doi":"10.1021/es802721d","usgsCitation":"Kinney, C.A., Furlong, E.T., Kolpin, D.W., Burkhardt, M.R., Zaugg, S.D., Werner, S.L., Bossio, J., and Benotti, M.J., 2009, Response to \"comment on 'bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure'\": Environmental Science & Technology, v. 43, no. 2, p. 545-547, https://doi.org/10.1021/es802721d.","productDescription":"3 p.","startPage":"545","endPage":"547","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":358218,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"43","issue":"2","noUsgsAuthors":false,"publicationDate":"2008-12-12","publicationStatus":"PW","scienceBaseUri":"5c10cd73e4b034bf6a7f8b6f","contributors":{"authors":[{"text":"Kinney, Chad A.","contributorId":198086,"corporation":false,"usgs":false,"family":"Kinney","given":"Chad","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":747595,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Furlong, Edward T. 0000-0002-7305-4603 efurlong@usgs.gov","orcid":"https://orcid.org/0000-0002-7305-4603","contributorId":740,"corporation":false,"usgs":true,"family":"Furlong","given":"Edward","email":"efurlong@usgs.gov","middleInitial":"T.","affiliations":[{"id":27111,"text":"National Water Quality Program","active":true,"usgs":true},{"id":5046,"text":"Branch of Analytical Serv (NWQL)","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true},{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":747596,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kolpin, Dana W. 0000-0002-3529-6505 dwkolpin@usgs.gov","orcid":"https://orcid.org/0000-0002-3529-6505","contributorId":1239,"corporation":false,"usgs":true,"family":"Kolpin","given":"Dana","email":"dwkolpin@usgs.gov","middleInitial":"W.","affiliations":[{"id":351,"text":"Iowa Water Science Center","active":true,"usgs":true}],"preferred":true,"id":747597,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Burkhardt, Mark R.","contributorId":27872,"corporation":false,"usgs":true,"family":"Burkhardt","given":"Mark","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":747598,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Zaugg, Steven D. sdzaugg@usgs.gov","contributorId":768,"corporation":false,"usgs":true,"family":"Zaugg","given":"Steven","email":"sdzaugg@usgs.gov","middleInitial":"D.","affiliations":[],"preferred":true,"id":747599,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Werner, Stephen L. slwerner@usgs.gov","contributorId":1199,"corporation":false,"usgs":true,"family":"Werner","given":"Stephen","email":"slwerner@usgs.gov","middleInitial":"L.","affiliations":[],"preferred":true,"id":747600,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Bossio, J.P.","contributorId":37959,"corporation":false,"usgs":true,"family":"Bossio","given":"J.P.","email":"","affiliations":[],"preferred":false,"id":747601,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Benotti, Mark J.","contributorId":190783,"corporation":false,"usgs":false,"family":"Benotti","given":"Mark","email":"","middleInitial":"J.","affiliations":[{"id":35387,"text":"Southern Nevada Water Authority","active":true,"usgs":false}],"preferred":false,"id":747602,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70037420,"text":"70037420 - 2009 - Alligators and crocodiles as indicators for restoration of Everglades ecosystems","interactions":[],"lastModifiedDate":"2014-04-11T11:03:46","indexId":"70037420","displayToPublicDate":"2009-01-01T07:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1456,"text":"Ecological Indicators","active":true,"publicationSubtype":{"id":10}},"title":"Alligators and crocodiles as indicators for restoration of Everglades ecosystems","docAbstract":"Alligators and crocodiles integrate biological impacts of hydrological operations, affecting them at all life stages through three key aspects of Everglades ecology: (1) food webs, (2) diversity and productivity, and (3) freshwater flow. Responses of crocodilians are directly related to suitability of environmental conditions and hydrologic change. Correlations between biological responses and environmental conditions contribute to an understanding of species' status and trends over time. Positive or negative trends of crocodilian populations relative to hydrologic changes permit assessment of positive or negative trends in restoration.
\nThe crocodilian indicator uses monitoring parameters (performance measures) that have been shown to be both effective and efficient in tracking trends. The alligator component uses relative density (reported as an encounter rate), body condition, and occupancy rates of alligator holes; the crocodile component uses juvenile growth and hatchling survival. We hypothesize that these parameters are correlated with hydrologic conditions including depth, duration, timing, spatial extent and water quality. Salinity is a critical parameter in estuarine habitats. Assessments of parameters defined for crocodilian performance measures support these hypotheses.
\nAlligators and crocodiles are the charismatic megafauna of the Everglades. They are both keystone and flagship species to which the public can relate. In addition, the parameters used to track trends are easy to understand. They provide answers to the following questions: How has the number of alligators or crocodiles changed? Are the animals fatter or thinner than they should be? Are the animals in the places (in terms of habitat and geography) where they should be?
\nAs surely as there is no other Everglades, no other single species defines the Everglades as does the American alligator. The Everglades is the only place in the world where both alligators and crocodiles exist. Crocodilians clearly respond to changes in hydrologic parameters of management interest. These relationships are easy to communicate and mean something to managers, decision makers, and the public. Having crocodilians on the list of system-wide, general indicators provides us with one of the most powerful tools we have to communicate progress of ecosystem restoration in Greater Everglades ecosystems to diverse audiences.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ecological Indicators","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.ecolind.2008.06.008","issn":"1470160X","usgsCitation":"Mazzotti, F., Best, G.R., Brandt, L., Cherkiss, M.S., Jeffery, B.M., and Rice, K.G., 2009, Alligators and crocodiles as indicators for restoration of Everglades ecosystems: Ecological Indicators, v. 9, no. 6 SUPPL., p. S137-S149, https://doi.org/10.1016/j.ecolind.2008.06.008.","productDescription":"15 p.","startPage":"S137","endPage":"S149","costCenters":[],"links":[{"id":217265,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.ecolind.2008.06.008"},{"id":245197,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Everglades","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -81.393156,25.842687 ], [ -81.393156,25.873513 ], [ -81.379211,25.873513 ], [ -81.379211,25.842687 ], [ -81.393156,25.842687 ] ] ] } } ] }","volume":"9","issue":"6 SUPPL.","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e96ce4b0c8380cd4828d","contributors":{"authors":[{"text":"Mazzotti, Frank J.","contributorId":100018,"corporation":false,"usgs":false,"family":"Mazzotti","given":"Frank J.","affiliations":[{"id":12557,"text":"University of Florida, FLREC","active":true,"usgs":false}],"preferred":false,"id":460974,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Best, G. Ronnie ronnie_best@usgs.gov","contributorId":4282,"corporation":false,"usgs":true,"family":"Best","given":"G.","email":"ronnie_best@usgs.gov","middleInitial":"Ronnie","affiliations":[{"id":5064,"text":"Southeast Regional Director's Office","active":true,"usgs":true}],"preferred":true,"id":460970,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Brandt, Laura A.","contributorId":18608,"corporation":false,"usgs":false,"family":"Brandt","given":"Laura A.","affiliations":[{"id":6987,"text":"U.S. Fish and Wildlife Sevice","active":true,"usgs":false}],"preferred":false,"id":460973,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Cherkiss, Michael S. 0000-0002-7802-6791 mcherkiss@usgs.gov","orcid":"https://orcid.org/0000-0002-7802-6791","contributorId":4571,"corporation":false,"usgs":true,"family":"Cherkiss","given":"Michael","email":"mcherkiss@usgs.gov","middleInitial":"S.","affiliations":[{"id":566,"text":"Southeast Ecological Science Center","active":true,"usgs":true},{"id":17705,"text":"Wetland and Aquatic Research Center","active":true,"usgs":true}],"preferred":true,"id":460971,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Jeffery, Brian M.","contributorId":16511,"corporation":false,"usgs":false,"family":"Jeffery","given":"Brian","email":"","middleInitial":"M.","affiliations":[{"id":12557,"text":"University of Florida, FLREC","active":true,"usgs":false}],"preferred":false,"id":460972,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Rice, Kenneth G. 0000-0001-8282-1088 krice@usgs.gov","orcid":"https://orcid.org/0000-0001-8282-1088","contributorId":117,"corporation":false,"usgs":true,"family":"Rice","given":"Kenneth","email":"krice@usgs.gov","middleInitial":"G.","affiliations":[{"id":566,"text":"Southeast Ecological Science Center","active":true,"usgs":true},{"id":17705,"text":"Wetland and Aquatic Research Center","active":true,"usgs":true}],"preferred":true,"id":460969,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70034882,"text":"70034882 - 2009 - Simulating hydrologic and hydraulic processes throughout the Amazon River Basin","interactions":[],"lastModifiedDate":"2017-04-03T14:57:17","indexId":"70034882","displayToPublicDate":"2009-01-01T00:00:00","publicationYear":"2009","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":"Simulating hydrologic and hydraulic processes throughout the Amazon River Basin","docAbstract":"Presented here is a model framework based on a land surface topography that can be represented with various degrees of resolution and capable of providing representative channel/floodplain hydraulic characteristics on a daily to hourly scale. The framework integrates two models: (1) a water balance model (WBM) for the vertical fluxes and stores of water in and through the canopy and soil layers based on the conservation of mass and energy, and (2) a routing model for the horizontal routing of surface and subsurface runoff and channel and floodplain waters based on kinematic and diffusion wave methodologies. The WBM is driven by satellite-derived precipitation (TRMM_3B42) and air temperature (MOD08_M3). The model's use of an irregular computational grid is intended to facilitate parallel processing for applications to continental and global scales. Results are presented for the Amazon Basin over the period Jan 2001 through Dec 2005. The model is shown to capture annual runoff totals, annual peaks, seasonal patterns, and daily fluctuations over a range of spatial scales (>1, 000 to < 4·7M km2). For the period of study, results suggest basin-wide total water storage changes in the Amazon vary by approximately + /− 5 to 10 cm, and the fractional components accounting for these changes are: root zone soil moisture (20%), subsurface water being routed laterally to channels (40%) and channel/floodplain discharge (40%). Annual variability in monthly water storage changes by + /− 2·5 cm is likely due to 0·5 to 1 month variability in the arrival of significant rainfall periods throughout the basin.
","language":"English","publisher":"Wiley","doi":"10.1002/hyp.7252","issn":"08856087","usgsCitation":"Beighley, R., Eggert, K., Dunne, T., He, Y., Gummadi, V., and Verdin, K., 2009, Simulating hydrologic and hydraulic processes throughout the Amazon River Basin: Hydrological Processes, v. 23, no. 8, p. 1221-1235, https://doi.org/10.1002/hyp.7252.","productDescription":"15 p.","startPage":"1221","endPage":"1235","numberOfPages":"15","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":243525,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":215703,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/hyp.7252"}],"volume":"23","issue":"8","noUsgsAuthors":false,"publicationDate":"2009-02-04","publicationStatus":"PW","scienceBaseUri":"505b8fd1e4b08c986b31915f","contributors":{"authors":[{"text":"Beighley, R.E.","contributorId":104302,"corporation":false,"usgs":true,"family":"Beighley","given":"R.E.","affiliations":[],"preferred":false,"id":448142,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Eggert, K.G.","contributorId":42450,"corporation":false,"usgs":true,"family":"Eggert","given":"K.G.","email":"","affiliations":[],"preferred":false,"id":448140,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dunne, T.","contributorId":25695,"corporation":false,"usgs":true,"family":"Dunne","given":"T.","email":"","affiliations":[],"preferred":false,"id":448138,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"He, Y.","contributorId":23319,"corporation":false,"usgs":true,"family":"He","given":"Y.","email":"","affiliations":[],"preferred":false,"id":448137,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Gummadi, V.","contributorId":33942,"corporation":false,"usgs":true,"family":"Gummadi","given":"V.","email":"","affiliations":[],"preferred":false,"id":448139,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Verdin, K.L.","contributorId":66438,"corporation":false,"usgs":true,"family":"Verdin","given":"K.L.","email":"","affiliations":[],"preferred":false,"id":448141,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70033864,"text":"70033864 - 2009 - Characterisation of carbon nanotubes in the context of toxicity studies","interactions":[],"lastModifiedDate":"2018-10-10T10:14:10","indexId":"70033864","displayToPublicDate":"2009-01-01T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":5522,"text":"Environmental Health","onlineIssn":"1476-069X","active":true,"publicationSubtype":{"id":10}},"title":"Characterisation of carbon nanotubes in the context of toxicity studies","docAbstract":"Nanotechnology has the potential to revolutionise our futures, but has also prompted concerns about the possibility that nanomaterials may harm humans or the biosphere. The unique properties of nanoparticles, that give them novel size dependent functionalities, may also have the potential to cause harm. Discrepancies in existing human health and environmental studies have shown the importance of good quality, well-characterized reference nanomaterials for toxicological studies.
Here we make a case for the importance of the detailed characterization of nanoparticles, using several methods, particularly to allow the recognition of impurities and the presence of chemically identical but structurally distinct phases. Methods to characterise fully, commercially available multi-wall carbon nanotubes at different scales, are presented.
","language":"English","publisher":"Springer","doi":"10.1186/1476-069X-8-S1-S3","issn":"1476069X","usgsCitation":"Berhanu, D., Dybowska, A., Misra, S., Stanley, C., Ruenraroengsak, P., Boccaccini, A., Tetley, T., Luoma, S., Plant, J., and Valsami-Jones, E., 2009, Characterisation of carbon nanotubes in the context of toxicity studies: Environmental Health, v. 8, no. Suppl. 1, 4 p., https://doi.org/10.1186/1476-069X-8-S1-S3.","productDescription":"4 p.","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":476199,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1186/1476-069x-8-s1-s3","text":"Publisher Index Page"},{"id":214322,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1186/1476-069X-8-S1-S3"},{"id":242039,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"8","issue":"Suppl. 1","noUsgsAuthors":false,"publicationDate":"2009-12-21","publicationStatus":"PW","scienceBaseUri":"5059f48ae4b0c8380cd4bd97","contributors":{"authors":[{"text":"Berhanu, D.","contributorId":86177,"corporation":false,"usgs":true,"family":"Berhanu","given":"D.","email":"","affiliations":[],"preferred":false,"id":442896,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dybowska, A.","contributorId":47171,"corporation":false,"usgs":true,"family":"Dybowska","given":"A.","email":"","affiliations":[],"preferred":false,"id":442890,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Misra, S.K.","contributorId":47989,"corporation":false,"usgs":true,"family":"Misra","given":"S.K.","email":"","affiliations":[],"preferred":false,"id":442891,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Stanley, C.J.","contributorId":31636,"corporation":false,"usgs":true,"family":"Stanley","given":"C.J.","email":"","affiliations":[],"preferred":false,"id":442889,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Ruenraroengsak, P.","contributorId":85845,"corporation":false,"usgs":true,"family":"Ruenraroengsak","given":"P.","email":"","affiliations":[],"preferred":false,"id":442895,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Boccaccini, A.R.","contributorId":59637,"corporation":false,"usgs":true,"family":"Boccaccini","given":"A.R.","email":"","affiliations":[],"preferred":false,"id":442893,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Tetley, T.D.","contributorId":52796,"corporation":false,"usgs":true,"family":"Tetley","given":"T.D.","email":"","affiliations":[],"preferred":false,"id":442892,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Luoma, S. N.","contributorId":86353,"corporation":false,"usgs":true,"family":"Luoma","given":"S. N.","affiliations":[],"preferred":false,"id":442897,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Plant, J.A.","contributorId":84137,"corporation":false,"usgs":true,"family":"Plant","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":442894,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Valsami-Jones, E.","contributorId":103088,"corporation":false,"usgs":true,"family":"Valsami-Jones","given":"E.","affiliations":[],"preferred":false,"id":442898,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}} ,{"id":70033924,"text":"70033924 - 2009 - Isomer-specific determination of 4-nonylphenols using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry","interactions":[],"lastModifiedDate":"2018-10-12T10:26:17","indexId":"70033924","displayToPublicDate":"2009-01-01T00:00:00","publicationYear":"2009","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":"Isomer-specific determination of 4-nonylphenols using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry","docAbstract":"Technical nonylphenol (tNP), used for industrial production of nonylphenol polyethoxylate surfactants, is a complex mixture of C3−10-phenols. The major components, 4-nonylphenols, are weak endocrine disruptors whose estrogenicities vary according to the structure of the branched nonyl group. Thus, accurate risk assessment requires isomer-specific determination of 4-NPs. Comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC/ToFMS) was used to characterize tNP samples obtained from seven commercial suppliers. Under optimal chromatographic conditions, 153−204 alkylphenol peaks, 59−66 of which were identified as 4-NPs, were detected. The 4-NPs comprised ∼86−94% of tNP, with 2-NPs and decylphenols making up ∼2−9% and ∼2−5%, respectively. The tNP products were analyzed for eight synthetic 4-NP isomers, and results were compared with published data based on GC/MS analysis. Significant differences were found among the products and between two samples from a single supplier. The enhanced resolution of GC × GC coupled with fast mass spectral data acquisition by ToFMS facilitated identification of all major 4-NP isomers and a number of previously unrecognized components. Analysis of tNP altered by the bacterium, Sphingobium xenophagum Bayram, revealed several persistent 4-NPs whose structures and estrogenicities are presently unknown. The potential of this technology for isomer-specific determination of 4-NP isomers in environmental matrices is demonstrated using samples of wastewater-contaminated groundwater and municipal wastewater.
The reactive transport of U(VI) in a well-characterized shallow alluvial aquifer at a former U(VI) mill located near Naturita, CO, was predicted for comparative purposes using a surface complexation model (SCM) and a constant K d approach to simulate U(VI) adsorption. The ground water at the site had U(VI) concentrations that ranged from 0.01 to 20 µM, alkalinities that ranged from 2.5 to 18 meq/L, and a nearly constant pH of 7.1. The SCM used to simulate U(VI) adsorption was previously determined independently using laboratory batch adsorption experiments. Simulations obtained using the SCM approach were compared with simulations that used a constant K d approach to simulate adsorption using previously determined site-specific K d values. In both cases, the ground water flow and transport models used a conceptual model that was previously calibrated to a chloride plume present at the site. Simulations with the SCM approach demonstrated that the retardation factor varied temporally and spatially because of the differential transport of alkalinity and dissolved U(VI) and the nonlinearity of the U(VI) adsorption. The SCM model also simulated a prolonged slow decline in U(VI) concentration, which was not simulated using a constant K d model. Simulations using the SCM approach and the constant K d approach were similar after 20 years of transport but diverged significantly after 60 years. The simulations demonstrate the need for site-specific geochemical information on U(VI) adsorption to produce credible simulations of future transport.
","language":"English","publisher":"Springer","doi":"10.1007/s10230-009-0064-x","issn":"10259112","usgsCitation":"Curtis, G., Kohler, M., and Davis, J., 2009, Comparing approaches for simulating the reactive transport of U(VI) in ground water: Mine Water and the Environment, v. 28, no. 2, p. 84-93, https://doi.org/10.1007/s10230-009-0064-x.","productDescription":"10 p.","startPage":"84","endPage":"93","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":216793,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10230-009-0064-x"},{"id":244685,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"28","issue":"2","noUsgsAuthors":false,"publicationDate":"2009-02-20","publicationStatus":"PW","scienceBaseUri":"5059f831e4b0c8380cd4cf2a","contributors":{"authors":[{"text":"Curtis, G.P.","contributorId":65619,"corporation":false,"usgs":true,"family":"Curtis","given":"G.P.","email":"","affiliations":[],"preferred":false,"id":445117,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kohler, M.","contributorId":32694,"corporation":false,"usgs":true,"family":"Kohler","given":"M.","affiliations":[],"preferred":false,"id":445116,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Davis, J.A.","contributorId":71694,"corporation":false,"usgs":true,"family":"Davis","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":445118,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70034346,"text":"70034346 - 2009 - Mercury sources, distribution, and bioavailability in the North Pacific Ocean: Insights from data and models","interactions":[],"lastModifiedDate":"2018-10-05T10:15:40","indexId":"70034346","displayToPublicDate":"2009-01-01T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1836,"text":"Global Biogeochemical Cycles","active":true,"publicationSubtype":{"id":10}},"title":"Mercury sources, distribution, and bioavailability in the North Pacific Ocean: Insights from data and models","docAbstract":"Fish harvested from the Pacific Ocean are a major contributor to human methylmercury (MeHg) exposure. Limited oceanic mercury (Hg) data, particularly MeHg, has confounded our understanding of linkages between sources, methylation sites, and concentrations in marine food webs. Here we present methylated (MeHg and dimethylmercury (Me2Hg)) and total Hg concentrations from 16 hydrographic stations in the eastern North Pacific Ocean. We use these data in combination with information from previous cruises and coupled atmospheric‐oceanic modeling results to better understand controls on Hg concentrations, distribution, and bioavailability. Total Hg concentrations (average 1.14 ± 0.38 pM) are elevated relative to previous cruises. Modeling results agree with observed increases and suggest that at present atmospheric Hg deposition rates, basin‐wide Hg concentrations will double relative to circa 1995 by 2050. Methylated Hg accounts for up to 29% of the total Hg in subsurface waters (average 260 ± 114 fM). We observed lower ambient methylated Hg concentrations in the euphotic zone and older, deeper water masses, which likely result from decay of MeHg and Me2Hg when net production is not occurring. We found a significant, positive linear relationship between methylated Hg concentrations and rates of organic carbon remineralization (r2 = 0.66, p < 0.001). These results provide evidence for the importance of particulate organic carbon (POC) transport and remineralization on the production and distribution of methylated Hg species in marine waters. Specifically, settling POC provides a source of inorganic Hg(II) to microbially active subsurface waters and can also provide a substrate for microbial activity facilitating water column methylation.
","language":"English","publisher":"AGU","doi":"10.1029/2008GB003425","issn":"08866236","usgsCitation":"Sunderland, E., Krabbenhoft, D., Moreau, J., Strode, S., and Landing, W., 2009, Mercury sources, distribution, and bioavailability in the North Pacific Ocean: Insights from data and models: Global Biogeochemical Cycles, v. 23, no. 2, https://doi.org/10.1029/2008GB003425.","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":476220,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2008gb003425","text":"Publisher Index Page"},{"id":244560,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":216675,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2008GB003425"}],"volume":"23","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a542de4b0c8380cd6ced7","contributors":{"authors":[{"text":"Sunderland, E.M.","contributorId":45546,"corporation":false,"usgs":true,"family":"Sunderland","given":"E.M.","email":"","affiliations":[],"preferred":false,"id":445335,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"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":445338,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Moreau, J.W.","contributorId":64457,"corporation":false,"usgs":true,"family":"Moreau","given":"J.W.","affiliations":[],"preferred":false,"id":445336,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Strode, S.A.","contributorId":73439,"corporation":false,"usgs":true,"family":"Strode","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":445337,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Landing, W.M.","contributorId":99303,"corporation":false,"usgs":true,"family":"Landing","given":"W.M.","email":"","affiliations":[],"preferred":false,"id":445339,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70034358,"text":"70034358 - 2009 - Linking hydraulic properties of fire-affected soils to infiltration and water repellency","interactions":[],"lastModifiedDate":"2012-03-12T17:21:46","indexId":"70034358","displayToPublicDate":"2009-01-01T00:00:00","publicationYear":"2009","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Linking hydraulic properties of fire-affected soils to infiltration and water repellency","docAbstract":"Heat from wildfires can produce a two-layer system composed of extremely dry soil covered by a layer of ash, which when subjected to rainfall, may produce extreme floods. To understand the soil physics controlling runoff for these initial conditions, we used a small, portable disk infiltrometer to measure two hydraulic properties: (1) near-saturated hydraulic conductivity, Kf and (2) sorptivity, S(??i), as a function of initial soil moisture content, ??i, ranging from extremely dry conditions (??i < 0.02 cm3 cm-3) to near saturation. In the field and in the laboratory replicate measurements were made of ash, reference soils, soils unaffected by fire, and fire-affected soils. Each has a different degrees of water repellency that influences Kf and S(??i). Values of Kf ranged from 4.5 ?? 10-3 to 53 ?? 10-3 cm s-1 for ash; from 0.93 ?? 10-3 to 130 ?? 10-3 cm s-1 for reference soils; and from 0.86 ?? 10-3 to 3.0 ?? 10-3 cm s-1, for soil unaffected by fire, which had the lowest values of Kf. Measurements indicated that S(??i) could be represented by an empirical non-linear function of ??i with a sorptivity maximum of 0.18-0.20 cm s-0.5, between 0.03 and 0.08 cm3 cm-3. This functional form differs from the monotonically decreasing non-linear functions often used to represent S(??i) for rainfall-runoff modeling. The sorptivity maximum may represent the combined effects of gravity, capillarity, and adsorption in a transitional domain corresponding to extremely dry soil, and moreover, it may explain the observed non-linear behavior, and the critical soil-moisture threshold of water repellent soils. Laboratory measurements of Kf and S(??i) are the first for ash and fire-affected soil, but additional measurements are needed of these hydraulic properties for in situ fire-affected soils. They provide insight into water repellency behavior and infiltration under extremely dry conditions. Most importantly, they indicate how existing rainfall-runoff models can be modified to accommodate a possible two-layer system in extremely dry conditions. These modified models can be used to predict floods from burned watersheds under these initial conditions.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.jhydrol.2009.10.015","issn":"00221694","usgsCitation":"Moody, J.A., Kinner, D., and Ubeda, X., 2009, Linking hydraulic properties of fire-affected soils to infiltration and water repellency: Journal of Hydrology, v. 379, no. 3-4, p. 291-303, https://doi.org/10.1016/j.jhydrol.2009.10.015.","startPage":"291","endPage":"303","numberOfPages":"13","costCenters":[],"links":[{"id":244722,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":216827,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jhydrol.2009.10.015"}],"volume":"379","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a47d4e4b0c8380cd679e3","contributors":{"authors":[{"text":"Moody, J. A.","contributorId":32930,"corporation":false,"usgs":true,"family":"Moody","given":"J.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":445396,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kinner, D.A.","contributorId":99265,"corporation":false,"usgs":true,"family":"Kinner","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":445397,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Ubeda, X.","contributorId":17847,"corporation":false,"usgs":true,"family":"Ubeda","given":"X.","email":"","affiliations":[],"preferred":false,"id":445395,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70034527,"text":"70034527 - 2009 - Hydrologic connectivity between landscapes and streams: Transferring reach‐ and plot‐scale understanding to the catchment scale","interactions":[],"lastModifiedDate":"2018-10-08T07:37:36","indexId":"70034527","displayToPublicDate":"2009-01-01T00:00:00","publicationYear":"2009","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":"Hydrologic connectivity between landscapes and streams: Transferring reach‐ and plot‐scale understanding to the catchment scale","docAbstract":"The relationship between catchment structure and runoff characteristics is poorly understood. In steep headwater catchments with shallow soils the accumulation of hillslope area (upslope accumulated area (UAA)) is a hypothesized first‐order control on the distribution of soil water and groundwater. Hillslope‐riparian water table connectivity represents the linkage between the dominant catchment landscape elements (hillslopes and riparian zones) and the channel network. Hydrologic connectivity between hillslope‐riparian‐stream (HRS) landscape elements is heterogeneous in space and often temporally transient. We sought to test the relationship between UAA and the existence and longevity of HRS shallow groundwater connectivity. We quantified water table connectivity based on 84 recording wells distributed across 24 HRS transects within the Tenderfoot Creek Experimental Forest (U.S. Forest Service), northern Rocky Mountains, Montana. Correlations were observed between the longevity of HRS water table connectivity and the size of each transect's UAA (r2 = 0.91). We applied this relationship to the entire stream network to quantify landscape‐scale connectivity through time and ascertain its relationship to catchment‐scale runoff dynamics. We found that the shape of the estimated annual landscape connectivity duration curve was highly related to the catchment flow duration curve (r2 = 0.95). This research suggests internal catchment landscape structure (topography and topology) as a first‐order control on runoff source area and whole catchment response characteristics.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2008WR007225","usgsCitation":"Jencso, K.G., McGlynn, B.L., Gooseff, M.N., Wondzell, S.M., Bencala, K.E., and Marshall, L.A., 2009, Hydrologic connectivity between landscapes and streams: Transferring reach‐ and plot‐scale understanding to the catchment scale: Water Resources Research, v. 45, no. 4, W04428; 16 p., https://doi.org/10.1029/2008WR007225.","productDescription":"W04428; 16 p.","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":487221,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://scholarworks.montana.edu/xmlui/handle/1/1554","text":"External Repository"},{"id":243877,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"45","issue":"4","noUsgsAuthors":false,"publicationDate":"2009-04-29","publicationStatus":"PW","scienceBaseUri":"505a35a3e4b0c8380cd600bf","contributors":{"authors":[{"text":"Jencso, Kelsey G.","contributorId":32375,"corporation":false,"usgs":false,"family":"Jencso","given":"Kelsey","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":446226,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McGlynn, Brian L.","contributorId":83012,"corporation":false,"usgs":true,"family":"McGlynn","given":"Brian","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":446228,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gooseff, Michael N.","contributorId":191367,"corporation":false,"usgs":false,"family":"Gooseff","given":"Michael","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":446225,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Wondzell, Steven M.","contributorId":80189,"corporation":false,"usgs":true,"family":"Wondzell","given":"Steven","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":446224,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Bencala, Kenneth E. kbencala@usgs.gov","contributorId":1541,"corporation":false,"usgs":true,"family":"Bencala","given":"Kenneth","email":"kbencala@usgs.gov","middleInitial":"E.","affiliations":[],"preferred":true,"id":446227,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Marshall, Lucy A. 0000-0003-0450-4292","orcid":"https://orcid.org/0000-0003-0450-4292","contributorId":198080,"corporation":false,"usgs":false,"family":"Marshall","given":"Lucy","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":446223,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70034621,"text":"70034621 - 2009 - Effects of simplifying fracture network representation on inert chemical migration in fracture-controlled aquifers","interactions":[],"lastModifiedDate":"2018-10-15T07:23:28","indexId":"70034621","displayToPublicDate":"2009-01-01T00:00:00","publicationYear":"2009","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":"Effects of simplifying fracture network representation on inert chemical migration in fracture-controlled aquifers","docAbstract":"[1] While it is widely recognized that highly permeable ‘large‐scale' fractures dominate chemical migration in many fractured aquifers, recent studies suggest that the pervasive ‘small‐scale’ fracturing once considered of less significance can be equally important for characterizing the spatial extent and residence time associated with transport processes. A detailed examination of chemical migration through fracture‐controlled aquifers is used to advance this conceptual understanding. The influence of fracture structure is evaluated by quantifying the effects to transport caused by a systematic removal of fractures from three‐dimensional discrete fracture models whose attributes are derived from geologic and hydrologic conditions at multiple field sites. Results indicate that the effects to transport caused by network simplification are sensitive to the fracture network characteristics, degree of network simplification, and plume travel distance, but primarily in an indirect sense since correlation to individual attributes is limited. Transport processes can be ‘enhanced’ or ‘restricted’ from network simplification meaning that the elimination of fractures may increase or decrease mass migration, mean travel time, dispersion, and tailing of the concentration plume. The results demonstrate why, for instance, chemical migration may not follow the classic advection‐dispersion equation where dispersion approximates the effect of the ignored geologic structure as a strictly additive process to the mean flow. The analyses further reveal that the prediction error caused by fracture network simplification is reduced by at least 50% using the median estimate from an ensemble of simplified fracture network models, and that the error from network simplification is at least 70% less than the stochastic variability from multiple realizations.