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Full-Text Articles in Physical Sciences and Mathematics

Relating Groundwater To Seasonal Wetlands In Southeastern Wisconsin, Usa, John D. Skalbeck, Donald M. Reed, Randall J. Hunt, Jamie D. Lambert Aug 2008

Relating Groundwater To Seasonal Wetlands In Southeastern Wisconsin, Usa, John D. Skalbeck, Donald M. Reed, Randall J. Hunt, Jamie D. Lambert

United States Geological Survey: Staff Publications

Historically, drier types of wetlands have been difficult to characterize and are not well researched. Nonetheless, they are considered to reflect the precipitation history with little, if any, regard for possible relation to groundwater. Two seasonal coastal wetland types (wet prairie, sedge meadow) were investigated during three growing seasons at three sites in the Lake Michigan Basin, Wisconsin, USA. The six seasonal wetlands were characterized using standard soil and vegetation techniques and groundwater measurements from the shallow and deep systems. They all met wetland hydrology criteria (e.g., water within 30 cm of land surface for 5% of the growing season) …


Mitochondrial Dna Evolution In The Anaxyrus Boreas Species Group, Anna M. Goebel, Tom A. Ranker, Paul Stephen Corn, Richard G. Olmstead Jul 2008

Mitochondrial Dna Evolution In The Anaxyrus Boreas Species Group, Anna M. Goebel, Tom A. Ranker, Paul Stephen Corn, Richard G. Olmstead

United States Geological Survey: Staff Publications

The Anaxyrus boreas species group currently comprises four species in western North America including the broadly distributed A. boreas, and three localized species, Anaxyrus nelsoni, Anaxyrus exsul and Anaxyrus canorus. Phylogenetic analyses of the mtDNA 12S rDNA, cytochrome oxidase I, control region, and restriction sites data, identified three major haplotype clades. The Northwest clade (NW) includes both subspecies of A. boreas and divergent minor clades in the middle Rocky Mountains, coastal, and central regions of the west and Pacific Northwest. The Southwest (SW) clade includes A. exsul, A. nelsoni, and minor clades in southern California. …


Occurrence And Fate Of Pesticides In Four Contrasting Agricultural Settings In The United States, Gregory V. Steele, Henry M. Johnson, Mark W. Sandstrom, Paul D. Capel, Jack E. Barbash Apr 2008

Occurrence And Fate Of Pesticides In Four Contrasting Agricultural Settings In The United States, Gregory V. Steele, Henry M. Johnson, Mark W. Sandstrom, Paul D. Capel, Jack E. Barbash

United States Geological Survey: Staff Publications

Occurrence and fate of 45 pesticides and 40 pesticide degradates were investigated in four contrasting agricultural settings—in Maryland, Nebraska, California, and Washington. Primary crops included corn at all sites, soybeans in Maryland, orchards in California and Washington, and vineyards in Washington. Pesticides and pesticide degradates detected in water samples from all four areas were predominantly from two classes of herbicides—triazines and chloroacetanilides; insecticides and fungicides were not present in the shallow ground water. In most samples, pesticide degradates greatly exceeded the concentrations of parent pesticide. In samples from Nebraska, the parent pesticide atrazine [6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4- diamine] was about the same concentration …


Transport And Fate Of Nitrate At The Ground-Water/Surface-Water Interface, Larry J. Puckett, Celia Zamora, Hedeff Essaid, John T. Wilson, Henry M. Johnson, Michael Brayton, Jason R. Vogel Apr 2008

Transport And Fate Of Nitrate At The Ground-Water/Surface-Water Interface, Larry J. Puckett, Celia Zamora, Hedeff Essaid, John T. Wilson, Henry M. Johnson, Michael Brayton, Jason R. Vogel

United States Geological Survey: Staff Publications

Although numerous studies of hyporheic exchange and denitrification have been conducted in pristine, high-gradient streams, few studies of this type have been conducted in nutrient-rich, low-gradient streams. This is a particularly important subject given the interest in nitrogen (N) inputs to the Gulf of Mexico and other eutrophic aquatic systems. A combination of hydrologic, mineralogical, chemical, dissolved gas, and isotopic data were used to determine the processes controlling transport and fate of 3− in streambeds at five sites across the USA. Water samples were collected from streambeds at depths ranging from 0.3 to 3 m at three to five …


Pesticides In Rain In Four Agricultural Watersheds In The United States, Jason R. Vogel, Michael S. Majewski, Paul D. Capel Apr 2008

Pesticides In Rain In Four Agricultural Watersheds In The United States, Jason R. Vogel, Michael S. Majewski, Paul D. Capel

United States Geological Survey: Staff Publications

Rainfall samples were collected during the 2003 and 2004 growing seasons at four agricultural locales across the USA in Maryland, Indiana, Nebraska, and California. The samples were analyzed for 21 insecticides, 18 herbicides, three fungicides, and 40 pesticide degradates. Data from all sites combined show that 7 of the 10 most frequently detected pesticides were herbicides, with atrazine (70%) and metolachlor (83%) detected at every site. Dacthal, acetochlor, simazine, alachlor, and pendimethalin were detected in more than 50% of the samples. Chlorpyrifos, carbaryl, and diazinon were the only insecticides among the 10 most frequently detected compounds. Of the remaining pesticide …


Using Heat To Characterize Streambed Water Flux Variability In Four Stream Reaches, Hedeff Essaid, Celia M. Zamora, Kathleen A. Mccarthy, Jason R. Vogel, John T. Wilson Apr 2008

Using Heat To Characterize Streambed Water Flux Variability In Four Stream Reaches, Hedeff Essaid, Celia M. Zamora, Kathleen A. Mccarthy, Jason R. Vogel, John T. Wilson

United States Geological Survey: Staff Publications

Estimates of streambed water fl ux are needed for the interpretation of streambed chemistry and reactions. Continuous temperature and head monitoring in stream reaches within four agricultural watersheds (Leary Weber Ditch, IN; Maple Creek, NE; DR2 Drain, WA; and Merced River, CA) allowed heat to be used as a tracer to study the temporal and spatial variability of fluxes through the streambed. Synoptic methods (seepage meter and differential discharge measurements) were compared with estimates obtained by using heat as a tracer. Water flux was estimated by modeling one-dimensional vertical flow of water and heat using the model VS2DH. Flux was …


California Drought, An Update April 2008, Baryohay Davidoff, Fawzi Karajeh, Dean Reynolds, Eric Senter, John Woodling Apr 2008

California Drought, An Update April 2008, Baryohay Davidoff, Fawzi Karajeh, Dean Reynolds, Eric Senter, John Woodling

United States Geological Survey: Staff Publications

TABLE OF CONTENTS

CHAPTER 1. RECENT HYDROLOGIC CONDITIONS AND IMPACTS

Introduction....................................................... 1

Water Year 2007 .................................................. 1

Drought in the Colorado River Basin ..................................................... 5

Drought and Dry Conditions in the Early 2000s .................................... 7

The 2001 Klamath Basin Drought Emergency ............................... 11

CHAPTER 2. PROGRAMMATIC AND INSTITUTIONAL UPDATES

The San Francisco Bay-Sacramento/San Joaquin River Delta.................................................................. 15

The Colorado River .................................................................... 16

State Financial Assistance to Local Agencies.................................... 17

Urban Water Management Planning ................................................... 20

Water Transfers .............................................................................. 20

Small Water Systems and Drought Preparedness ................................. 21


Intelligent Environmental Decision Support Systems, M. Sànchez-Marrè, K. Gibert, R. S. Sojda, J. P. Steyer, P. Struss, I. Rodríguez-Roda, J. Comas, V. Brilhante, E. A. Roehl Jan 2008

Intelligent Environmental Decision Support Systems, M. Sànchez-Marrè, K. Gibert, R. S. Sojda, J. P. Steyer, P. Struss, I. Rodríguez-Roda, J. Comas, V. Brilhante, E. A. Roehl

United States Geological Survey: Staff Publications

Introduction
Complexity of environmental systems
New tools for a new paradigm
Intelligent Environmental Decision Support Systems (IEDSS)
IEDSS development
About Uncertainty Management
Temporal Reasoning
Featuring the problem
Approaches to temporal reasoning
Case-based reasoning for temporal reasoning
Geographic Information and Spatial Reasoning
Understanding spatial reasoning
Kriging and variants
Representing change/time steps/feedback loops
Middleware. blackboards and communication protocols
Multiagent systems
Evaluation of IEDSS and Benchmarking
Benchmarking
Conclusions and Future Trends


Estimation Of Groundwater And Nutrient Fluxes To The Neuse River Estuary, North Carolina, Timothy B. Spruill, John F. Bratton Jan 2008

Estimation Of Groundwater And Nutrient Fluxes To The Neuse River Estuary, North Carolina, Timothy B. Spruill, John F. Bratton

United States Geological Survey: Staff Publications

A study was conducted between April 2004 and September 2005 to estimate groundwater and nutrient discharge to the Neuse River estuary in North Carolina. The largest groundwater fluxes were observed to occur generally within 20 m of the shoreline. Groundwater flux estimates based on seepage meter measurements ranged from 2.86×108 to 4.33×108 m3 annually and are comparable to estimates made using radon, a simple water-budget method, and estimates derived by using Darcy’s Law and previously published general aquifer characteristics of the area. The lower groundwater flux estimate (equal to about 9 m3 s-1), which …


Geochemical Evidence For Hydroclimatic Variability Over The Last 2460 Years From Crevice Lake In Yellowstone National Park, Usa, Lora R. Stevens, Walter E. Dean Jan 2008

Geochemical Evidence For Hydroclimatic Variability Over The Last 2460 Years From Crevice Lake In Yellowstone National Park, Usa, Lora R. Stevens, Walter E. Dean

United States Geological Survey: Staff Publications

A 2460-year-long hydroclimatic record for Crevice Lake, Yellowstone National Park, Montana was constructed from the δ18O values of endogenic carbonates. The δ18O record is compared to the Palmer Hydrologic Drought Index (PHDI) and Pacific Decadal Oscillation (PDO) indices, as well as inferred discharge of the Yellowstone River. During the last century, high δ18O values coincide with drought conditions and the warm phase of the PDO index. Low δ18O values coincide with wet years and a negative PDO index. Comparison of tree-ring inferred discharge of the Yellowstone River with the δ18O …


Integrated Modelling Frameworks For Environmental Assessment And Decision Support, A. E. Rizzoli, G. Leavesley, J. C. Ascough Ii, R. M. Argent, I. N. Athanasiadis, V. Brilhante, F. H. A. Claeys, O. David, M. Donatelli, P. Gijsbers, D. Havlik, A. Kassahun, P. Krause, N. W. T. Quinn, H. Scholten, R. S. Sojda, F. Villa Jan 2008

Integrated Modelling Frameworks For Environmental Assessment And Decision Support, A. E. Rizzoli, G. Leavesley, J. C. Ascough Ii, R. M. Argent, I. N. Athanasiadis, V. Brilhante, F. H. A. Claeys, O. David, M. Donatelli, P. Gijsbers, D. Havlik, A. Kassahun, P. Krause, N. W. T. Quinn, H. Scholten, R. S. Sojda, F. Villa

United States Geological Survey: Staff Publications

As argued in Chapter 1, modern management of environmental resources defines problems from a holistic and integrated perspective, thereby imposing strong requirements on Environmental Decision Support Systems (EDSSs) and Integrated Assessment Tools (IATs). These systems and tools tend to be increasingly complex in terms of software architecture and computational power in order to cope with the type of problems they must solve. For instance, the discipline of Integrated Assessment (IA) needs tools that arc able to span a wide range of disciplines, from socio-economics to ecology to hydrology. Such tools must support a wide range of methodologies and techniques like …


Human-Induced Changes In The Hydrology Of The Western United States, Tim P. Barnett, David W. Pierce, Hugo G. Hidalgo, Celine Bonfils, Benjamin D. Santer, Tapash Das, Govindasamy Bala, Andrew W. Wood, Toru Nozawa, Arthur A. Mirin, Daniel R. Cayan, Michael D. Dettinger Jan 2008

Human-Induced Changes In The Hydrology Of The Western United States, Tim P. Barnett, David W. Pierce, Hugo G. Hidalgo, Celine Bonfils, Benjamin D. Santer, Tapash Das, Govindasamy Bala, Andrew W. Wood, Toru Nozawa, Arthur A. Mirin, Daniel R. Cayan, Michael D. Dettinger

United States Geological Survey: Staff Publications

Observations have shown that the hydrological cycle of the western United States changed significantly over the last half of the 20th century. We present a regional, multivariable climate change detection and attribution study, using a high-resolution hydrologic model forced by global climate models, focusing on the changes that have already affected this primarily arid region with a large and growing population. The results show that up to 60% of the climate-related trends of river flow, winter air temperature, and snow pack between 1950 and 1999 are human-induced. These results are robust to perturbation of study variates and methods. They portend, …


Downflow Limestone Beds For Treatment Of Net-Acidic, Oxic, Iron-Laden Drainage From A Flooded Anthracite Mine, Pennsylvania, Usa: 1. Field Evaluation, Charles A. Cravotta Iii, Suzanne J. Ward Jan 2008

Downflow Limestone Beds For Treatment Of Net-Acidic, Oxic, Iron-Laden Drainage From A Flooded Anthracite Mine, Pennsylvania, Usa: 1. Field Evaluation, Charles A. Cravotta Iii, Suzanne J. Ward

United States Geological Survey: Staff Publications

Passive-treatment systems that route acidic mine drainage (AMD) through crushed limestone and/or organic-rich substrates have been used to remove the acidity and metals from various AMD sources, with a wide range of effects. This study evaluates treatment of net-acidic, oxic, iron-laden AMD with limestone alone, and with organic-rich compost layered with the limestone. In the fall of 2003, a treatment system consisting of two parallel, 500-m2 downflow cells followed by a 400-m2 aerobic settling pond and wetland was installed to neutralize the AMD from the Bell Mine, a large source of AMD and baseflow to the Schuylkill River …


The Threat Of The Non-Native Neotropical Rust Puccinia Psidii To Hawaiian Biodiversity And Native Ecosystems: A Case Example Of The Need For Prevention, Lloyd Loope, Janice Uchida, Loyal Mehrhoff Jan 2008

The Threat Of The Non-Native Neotropical Rust Puccinia Psidii To Hawaiian Biodiversity And Native Ecosystems: A Case Example Of The Need For Prevention, Lloyd Loope, Janice Uchida, Loyal Mehrhoff

United States Geological Survey: Staff Publications

The threat of invasive species to natural areas presents enormous challenges, but there are opportunities for working toward solutions, often in conjunction with agricultural and forestry perspectives. There is a growing awareness of the danger to botanical biodiversity and conservation from “emerging infectious diseases” that have increased in incidence, geographical distribution, or host range/pathogenicity; have newly evolved characteristics; and/or have been newly discovered (Anderson et al. 2004). There is a heightened concern for forest health due to accelerating worldwide movement of plant pathogens (e.g., with ineffective quarantine measures) that negatively affect both biodiversity and commercial forestry (Wingfield 2003). An important …


Environmental Contaminant Hazards To Wildlife At National Capital Region And Mid-Atlantic National Park Service Units, Barnett A. Rattner, Betty K. Ackerson Jan 2008

Environmental Contaminant Hazards To Wildlife At National Capital Region And Mid-Atlantic National Park Service Units, Barnett A. Rattner, Betty K. Ackerson

United States Geological Survey: Staff Publications

Part of the mission of the National Park Service (NPS) entails preservation of natural resources, processes, systems, and associated values of its units in an unimpaired condition. Environmental contamination and pollution processes are well recognized stressors that can adversely affect park units and are addressed by NPS management policies and plans. Nonetheless, biota remain at risk to contaminants at many NPS units. One U.S. Department of the Interior activity that addresses pollution hazards is the Biomonitoring of Environmental Status and Trends project (Zylstra 1994). Its does so through active field monitoring and by use of decision support tools, including the …


Comparison Of Total Mercury And Methylmercury Cycling At Five Sites Using The Small Watershed Approach, James B. Shanley, M. Alisa Mast, Donald H. Campbell, George R. Aiken, David P. Krabbenhoft, Randall J. Hunt, John F. Walker, Paul F. Schuster, Ann Chalmers, Brent T. Aulenbach, Norman E. Peters, Mark Marvin-Dipasquale, David W. Clow, Martin M. Shafer Jan 2008

Comparison Of Total Mercury And Methylmercury Cycling At Five Sites Using The Small Watershed Approach, James B. Shanley, M. Alisa Mast, Donald H. Campbell, George R. Aiken, David P. Krabbenhoft, Randall J. Hunt, John F. Walker, Paul F. Schuster, Ann Chalmers, Brent T. Aulenbach, Norman E. Peters, Mark Marvin-Dipasquale, David W. Clow, Martin M. Shafer

United States Geological Survey: Staff Publications

The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L-1 and MeHg was less than 0.2 ng L-1. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with …


Influence Of Plankton Mercury Dynamics And Trophic Pathways On Mercury Concentrations Of Top Predator Fish Of A Mining-Impacted Reservoir, A. Robin Stewart, Michael K. Saiki, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, David P. Krabbenhoft Jan 2008

Influence Of Plankton Mercury Dynamics And Trophic Pathways On Mercury Concentrations Of Top Predator Fish Of A Mining-Impacted Reservoir, A. Robin Stewart, Michael K. Saiki, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, David P. Krabbenhoft

United States Geological Survey: Staff Publications

Physical and biogeochemical characteristics of the aquatic environment that affect growth dynamics of phytoplankton and the zooplankton communities that depend on them may also affect uptake of methylmercury (MeHg) into the pelagic food web of oligotrophic reservoirs. We evaluated changes in the quality and quantity of suspended particulate material, zooplankton taxonomy, and MeHg concentrations coincident with seasonal changes in water storage of a mining-impacted reservoir in northern California, USA. MeHg concentrations in bulk zooplankton increased from 4 ng·g–1 at low water to 77 ± 6.1 ng·g–1 at high water and were positively correlated with cladoceran biomass (r = …


Development And Evaluation Of Geochemical Methods For The Sourcing Of Archaeological Maize, L.V. Benson, H. E. Taylor, K.A. Peterson, B.D. Shattuck, C.A. Ramotnik, J.R. Stein Jan 2008

Development And Evaluation Of Geochemical Methods For The Sourcing Of Archaeological Maize, L.V. Benson, H. E. Taylor, K.A. Peterson, B.D. Shattuck, C.A. Ramotnik, J.R. Stein

United States Geological Survey: Staff Publications

Strontium (Sr)-isotope values on bone from deer mice pairs from 12 field sites in the Chaco Canyon area, New Mexico, were compared with isotope values of synthetic soil waters from the same fields. The data indicate that mice obtain Sr from near-surface sources and that soil samples collected at depths ranging from 25 to 95 cm contain Sr that is more accessible to the deep roots of maize; thus, synthetic soil solutions provide better data for the sourcing of archaeological maize. However, the Sr-isotope composition of mice may be more valuable in sourcing archaeological remains of animals such as rabbit, …


Management And Conservation Note: Conserving Waste Rice For Wintering Waterfowl In The Mississippi Alluvial Valley, Jennifer P. Kross, Richard M. Kaminski, Aaron T. Pearse Jan 2008

Management And Conservation Note: Conserving Waste Rice For Wintering Waterfowl In The Mississippi Alluvial Valley, Jennifer P. Kross, Richard M. Kaminski, Aaron T. Pearse

United States Geological Survey: Staff Publications

The Mississippi Alluvial Valley (MAV), USA, is an internationally important migration and wintering region for North American waterfowl (Reinecke et al. 1989). The Lower Mississippi Valley Joint Venture (LMVJV) assumes food availability is the primary factor influencing carrying capacity of wintering waterfowl in this region (Reinecke and Loesch 1996). Because much of the MAV was converted from a seasonally flooded bottomland-hardwood ecosystem to a landscape dominated by agriculture, the LMVJV has incorporated estimates of the abundance of agricultural seeds such as rice into habitat conservation plans (Reinecke et al. 1988, Fredrickson et al. 2005). Biologists designed these plans to provide …


Late-Seasonal A Ctivity And Diet Of The Eveninc Bat (Nycticeius Humeralis) In Nebraska, Keith Geluso, Jason P. Damm, Ernest W. Valdez Jan 2008

Late-Seasonal A Ctivity And Diet Of The Eveninc Bat (Nycticeius Humeralis) In Nebraska, Keith Geluso, Jason P. Damm, Ernest W. Valdez

United States Geological Survey: Staff Publications

In North America, Nebraska represents part of the northwestern edge of the distribution for the evening bat (Nycticeius humeralis). To date, little information on this bat’s natural history has been published from the state or from other parts of the Great Plains. Here we report on aspects of its natural history in Nebraska from 2 localities. In late summer and early autumn of 2006, we documented individuals farther west in Nebraska (Harlan County) than previously reported and determined that individuals fed mainly on Coleoptera and Hymenoptera. In 2006, evening bats appeared to migrate from Nebraska during late September–early …


Pesticide Fate And Transport Throughout Unsaturated Zones In Five Agricultural Settings, Usa, Tracy C. Hancock, Mark W. Sandstrom, Jason R. Vogel, Richard M.T. Webb, E. Randall Bayless, Jack E. Barbash Jan 2008

Pesticide Fate And Transport Throughout Unsaturated Zones In Five Agricultural Settings, Usa, Tracy C. Hancock, Mark W. Sandstrom, Jason R. Vogel, Richard M.T. Webb, E. Randall Bayless, Jack E. Barbash

United States Geological Survey: Staff Publications

Pesticide transport through the unsaturated zone is a function of chemical and soil characteristics, application, and water recharge rate. The fate and transport of 82 pesticides and degradates were investigated at five different agricultural sites. Atrazine and metolachlor, as well as several of the degradates of atrazine, metolachlor, acetochlor, and alachlor, were frequently detected in soil water during the 2004 growing season, and degradates were generally more abundant than parent compounds. Metolachlor and atrazine were applied at a Nebraska site the same year as sampling, and focused recharge coupled with the short time since application resulted in their movement in …


Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa, Erin Muths, David S. Pilliod, Lauren J. Livo Jan 2008

Distribution And Environmental Limitations Of An Amphibian Pathogen In The Rocky Mountains, Usa, Erin Muths, David S. Pilliod, Lauren J. Livo

United States Geological Survey: Staff Publications

Amphibian populations continue to be imperiled by the chytrid fungus (Batrachochytrium dendrobatidis). Understanding where B. dendrobatidis (Bd) occurs and how it may be limited by environmental factors is critical to our ability to effectively conserve the amphibians affected by Bd. We sampled 1247 amphibians (boreal toads and surrogates) at 261 boreal toad (Bufo boreas) breeding sites (97 clusters) along an 11° latitudinal gradient in the Rocky Mountains to determine the distribution of B. dendrobatidis and examine environmental factors, such as temperature and elevation, that might affect its distribution. The fungus was detected at …


Geochemical Evidence For Airborne Dust Additions To Soils In Channel Islands National Park, California, Daniel R. Muhs, James R. Budahn, Donald L. Johnson, Marith Reheis, Jossh Beann, Gary Skipp, Eric Fischer, Julia A. Jones Jan 2008

Geochemical Evidence For Airborne Dust Additions To Soils In Channel Islands National Park, California, Daniel R. Muhs, James R. Budahn, Donald L. Johnson, Marith Reheis, Jossh Beann, Gary Skipp, Eric Fischer, Julia A. Jones

United States Geological Survey: Staff Publications

There is an increasing awareness that dust plays important roles in climate change, biogeochemical cycles, nutrient supply to ecosystems, and soil formation. In Channel Islands National Park, California, soils are clay-rich Vertisols or Alfi sols and Mollisols with vertic properties. The soils are overlain by silt-rich mantles that contrast sharply with the underlying clay-rich horizons. Silt mantles contain minerals that are rare or absent in the volcanic rocks that dominate these islands. Immobile trace elements (Sc-Th-La and Ta-Nd-Cr) and rare-earth elements show that the basalt and andesite on the islands have a composition intermediate between upper-continental crust and oceanic crust. …


Isotopic Evidence For The Diversity Of Late Quaternary Loess In Nebraska: Glaciogenic And Nonglaciogenic Sources, John N. Aleinikoff, Daniel R. Muhs, E. Arthur Bettis Iii, William C. Johnson, C. Mark Fanning, Rachel Benton Jan 2008

Isotopic Evidence For The Diversity Of Late Quaternary Loess In Nebraska: Glaciogenic And Nonglaciogenic Sources, John N. Aleinikoff, Daniel R. Muhs, E. Arthur Bettis Iii, William C. Johnson, C. Mark Fanning, Rachel Benton

United States Geological Survey: Staff Publications

Pb isotope compositions of detrital K-feldspars and U-Pb ages of detrital zircons are used as indicators for determining the sources of Peoria Loess deposited during the last glacial period (late Wisconsin, ca. 25–14 ka) in Nebraska and western Iowa. Our new data indicate that only loess adjacent to the Platte River has Pb isotopic characteristics suggesting derivation from this river. Most Peoria Loess in central Nebraska (up to 20 m thick) is non-glaciogenic, on the basis of Pb isotope ratios in K-feldspars and the presence of 34-Ma detrital zircons. These isotopic characteristics suggest derivation primarily from the Oligocene White River …


Influence Of Fipronil Compounds And Rice-Cultivation Land-Use Intensity On Macroinvertebrate Communities In Streams Of Southwestern Louisiana, Usa, Scott V. Mize, Stephen D. Porter, Dennis K. Demcheck Jan 2008

Influence Of Fipronil Compounds And Rice-Cultivation Land-Use Intensity On Macroinvertebrate Communities In Streams Of Southwestern Louisiana, Usa, Scott V. Mize, Stephen D. Porter, Dennis K. Demcheck

United States Geological Survey: Staff Publications

Laboratory tests of fipronil and its degradation products have revealed acute lethal toxicity at very low concentrations (LC50) of <0.5 μg/L to selected aquatic macroinvertebrates. In streams draining basins with intensive rice cultivation in southwestern Louisiana, USA, concentrations of fipronil compounds were an order of magnitude larger than the LC50. The abundance (p=-0.64; p=0.015) and taxa richness (r2=0.515, p<0.005) of macroinvertebrate communities declined significantly with increases in concentrations of fipronil compounds and rice-cultivation land-use intensity. Macroinvertebrate community tolerance scores increased linearly (r2=0.442, p < 0.005) with increases in the percentage of rice cultivation in the basins, indicating increasingly degraded stream conditions. Similarly, macroinvertebrate community-tolerance scores increased rapidly as fipronil concentrations approached about 1 μg/L. Pesticide toxicity index determinations indicated that aquatic macroinvertebrates respond to a gradient of fipronil compounds in water although stream size and habitat cannot be ruled out as contributing influences.


Bioaccumulation Of Pharmaceuticals And Other Anthropogenic Waste Indicators In Earthworms From Agricultural Soil Amended With Biosolid Or Swine Manure, Chad Kinney, Edward Furlong, Dana Kolpin, Mark Burkhardt, Steven Zaugg, Stephen Werner, Joseph Bossio, Mark Benotti Jan 2008

Bioaccumulation Of Pharmaceuticals And Other Anthropogenic Waste Indicators In Earthworms From Agricultural Soil Amended With Biosolid Or Swine Manure, Chad Kinney, Edward Furlong, Dana Kolpin, Mark Burkhardt, Steven Zaugg, Stephen Werner, Joseph Bossio, Mark Benotti

United States Geological Survey: Staff Publications

Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied biosolids and livestock manure to earthworms. The sites consisted of a soybean field with no amendments of human or livestock waste (Site 1), a soybean field amended with biosolids from a municipal wastewater treatment plant (Site 2), and a cornfield amended with swine manure (Site 3). The biosolid applied to Site 2 contained …


Origin And Paleoclimatic Signifi Cance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton Jan 2008

Origin And Paleoclimatic Signifi Cance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton

United States Geological Survey: Staff Publications

Loess is one of the most extensive surfi cial geologic deposits in mid-continental North America, particularly in the central Great Plains region of Nebraska. Last-glacial-age loess (Peoria Loess) reaches its greatest known thickness in the world in this area. New stratigraphic, geochronologic, mineralogic, and geochemical data yield information about the age and provenance of Peoria Loess, as well as evaluation of recent climate models.


Sacramento-San Joaquin Delta Regional Ecosystem Restoration Implementation Plan, Charles N. Alpers, Collin Eagles-Smith, Chris Foe, Susan Klasing, Mark C. Marvin-Dipasquale, Darell G. Slotton, Lisamarie Windham-Myers Jan 2008

Sacramento-San Joaquin Delta Regional Ecosystem Restoration Implementation Plan, Charles N. Alpers, Collin Eagles-Smith, Chris Foe, Susan Klasing, Mark C. Marvin-Dipasquale, Darell G. Slotton, Lisamarie Windham-Myers

United States Geological Survey: Staff Publications

Mercury has been identified as an important contaminant in the Delta, based on elevated concentrations of methylmercury (a toxic, organic form that readily bioaccumulates) in fish and wildlife. There are health risks associated with human exposure to methylmercury by consumption of sport fish, particularly top predators such as bass species. Original mercury sources were upstream tributaries where historical mining of mercury in the Coast Ranges and gold in the Sierra Nevada and Klamath-Trinity Mountains caused contamination of water and sediment on a regional scale. Remediation of abandoned mine sites may reduce local sources in these watersheds, but much of the …


Impact Of Drought On Prehistoric Western Native Americans, Larry Benson Jan 2008

Impact Of Drought On Prehistoric Western Native Americans, Larry Benson

United States Geological Survey: Staff Publications

Some droughts that occurred during the so-called Medieval Climate Anomaly (approximately AD 800-1300) appear to have been catalysts for major changes in settlement patterns of two western Native American groups - the Lovelock culture in Nevada’s Great Basin and the Anasazi people of the Four Corners area. Both groups’ subsistence bases were impacted by diminished water supplies associated with prolonged drought, leading to the dispersal of these Native Americans from their former territories.

Tree-ring-based Palmer Drought Severity Index (PDSI) reconstructions by Cook et al. (2004) indicate that over 50% of the western U.S. experienced drought conditions during the middle-12th and …


Range-Wide Phylogeographic Analysis Of The Spotted Frog Complex (Rana Luteiventris And Rana Pretiosa) In Northwestern North America, W. Chris Funk, Christopher A. Pearl, Hope M. Draheim, Michael J. Adams, Thomas D. Mullins, Susan M. Haig Jan 2008

Range-Wide Phylogeographic Analysis Of The Spotted Frog Complex (Rana Luteiventris And Rana Pretiosa) In Northwestern North America, W. Chris Funk, Christopher A. Pearl, Hope M. Draheim, Michael J. Adams, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

The dynamic geological and climatic history of northwestern North America has made it a focal region for phylogeography. We conducted a range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) across its range in northwestern North America to understand its evolutionary history and the distribution of clades to inform conservation of R. pretiosa and Great Basin R. luteiventris, candidates for listing under the US Endangered Species Act. Mitochondrial DNA sequence data from a segment of the cytochrome b gene were obtained from 308 R. luteiventris and R. pretiosa from 96 sites. Phylogenetic analysis …