Anthropogenic influences on the input and biogeochemical cycling of nutrients and mercury in Great Salt Lake, Utah, USA
D. Naftz, C. Angeroth, T. Kenney, B. Waddell, N. Darnall, S. Silva, C. Perschon, J. Whitehead
2008, Applied Geochemistry (23) 1731-1744
Despite the ecological and economic importance of Great Salt Lake (GSL), little is known about the input and biogeochemical cycling of nutrients and trace elements in the lake. In response to increasing public concern regarding anthropogenic inputs to the GSL ecosystem, the US Geological Survey (USGS) and US Fish and...
Pathogen and chemical transport in the karst limestone of the Biscayne aquifer: 2. Chemical retention from diffusion and slow advection
Allen M. Shapiro, Robert A. Renken, Ronald W. Harvey, Michael R. Zygnerski, David W. Metge
2008, Water Resources Research (44)
A tracer experiment, using a nonreactive tracer, was conducted as part of an investigation of the potential for chemical and pathogen migration to public supply wells that draw groundwater from the highly transmissive karst limestone of the Biscayne aquifer in southeastern Florida. The tracer was injected into the formation over...
Evaluation of statistical treatments of left-censored environmental data using coincident uncensored data sets: I. Summary statistics
Ronald C. Antweiler, Howard E. Taylor
2008, Environmental Science & Technology (42) 3732-3738
The main classes of statistical treatment of below-detection limit (left-censored) environmental data for the determination of basic statistics that have been used in the literature are substitution methods, maximum likelihood, regression on order statistics (ROS), and nonparametric techniques. These treatments, along with using all instrument-generated data (even those below detection),...
Chemical contaminants, health indicators, and reproductive biomarker responses in fish from rivers in the Southeastern United States
J.E. Hinck, V. S. Blazer, N. D. Denslow, K. R. Echols, R.W. Gale, C. Wieser, T.W. May, M. Ellersieck, J.J. Coyle, D. E. Tillitt
2008, Science of the Total Environment (390) 538-557
Largemouth bass (Micropterus salmoides) and common carp (Cyprinus carpio) were collected from 13 sites located in the Mobile (MRB), Apalachicola–Flint–Chattahoochee (ARB), Savannah (SRB), and Pee Dee (PRB) River Basins to document spatial trends in accumulative chemical contaminants, health indicators, and reproductive biomarkers. Organochlorine residues,...
Decomposition of soil organic matter from boreal black spruce forest: Environmental and chemical controls
K.P. Wickland, J. C. Neff
2008, Biogeochemistry (87) 29-47
Black spruce forests are a dominant covertype in the boreal forest region, and they inhabit landscapes that span a wide range of hydrologic and thermal conditions. These forests often have large stores of soil organic carbon. Recent increases in temperature at northern latitudes may be stimulating decomposition rates of...
Probable flood predictions in ungauged coastal basins of El Salvador
M.J. Friedel, M.E. Smith, A.M.E. Chica, D. Litke
2008, Conference Paper, Journal of Hydrologic Engineering
A regionalization procedure is presented and used to predict probable flooding in four ungauged coastal river basins of El Salvador: Paz, Jiboa, Grande de San Miguel, and Goascoran. The flood-prediction problem is sequentially solved for two regions: upstream mountains and downstream alluvial plains. In the upstream mountains, a set of...
Determination of dominant biogeochemical processes in a contaminated aquifer-wetland system using multivariate statistical analysis
S. E. Baez-Cazull, J.T. McGuire, I.M. Cozzarelli, M.A. Voytek
2008, Journal of Environmental Quality (37) 30-46
Determining the processes governing aqueous biogeochemistry in a wetland hydrologically linked to an underlying contaminated aquifer is challenging due to the complex exchange between the systems and their distinct responses to changes in precipitation, recharge, and biological activities. To evaluate temporal and spatial processes in the wetland-aquifer system, water samples...
Hydrochemical characterization of groundwater in the Akyem area, Ghana
B. Banoeng-Yakubo, S.M. Yidana, Y. Anku, T. Akabzaa, D. Asiedu
2008, Journal of Environmental Hydrology (16) 1-12
The Akyem area is a small farming community located in southeastern Ghana. Groundwater samples from wells in the area were analyzed for concentrations of the major ions, silica, electrical conductivity and pH. The objective was to determine the main controls on the hydrochemistry of ground-water. Mass balance modeling was used...
Bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure
C.A. Kinney, E. T. Furlong, D.W. Kolpin, M.R. Burkhardt, S.D. Zaugg, S.L. Werner, J.P. Bossio, M.J. Benotti
2008, Environmental Science & Technology (42) 1863-1870
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...
Do beavers promote the invasion of non-native Tamarix in the Grand Canyon riparian zone
S.G. Mortenson, P.J. Weisberg, B.E. Ralston
2008, Wetlands (28) 666-675
Beavers (Castor canadensis Kuhl) can influence the competitive dynamics of plant species through selective foraging, collection of materials for dam creation, and alteration of hydrologic conditions. In the Grand Canyon National Park, the native Salix gooddingii C.R.Ball (Goodding's willow) and Salix exigua Nutt. (coyote willow) are a staple food of...
Characterization and cycling of atmospheric mercury along the central US Gulf Coast
M.A. Engle, M.T. Tate, D. P. Krabbenhoft, A. Kolker, M.L. Olson, E.S. Edgerton, J.F. DeWild, A.K. McPherson
2008, Applied Geochemistry (23) 419-437
Concentrations of atmospheric Hg species, elemental Hg (Hg∘), reactive gaseous Hg (RGM), and fine particulate Hg (Hg-PM2.5) were measured at a coastal site near Weeks Bay, Alabama from April to August, 2005 and January to May, 2006. Mean concentrations of the species were...
In situ estimation of the effective chemical diffusion coefficient of a rock matrix in a fractured aquifer
R.A. Gebrekristos, A.M. Shapiro, B.H. Usher
2008, Hydrogeology Journal (16) 629-639
An in situ method of estimating the effective diffusion coefficient for a chemical constituent that diffuses into the primary porosity of a rock is developed by abruptly changing the concentration of the dissolved constituent in a borehole in contact with the rock matrix and monitoring the time-varying concentration. The...
Biomarkers of mercury exposure at a mercury recycling facility in Ukraine
H.J. Gibb, K. Kozlov, J.P. Buckley, J. Centeno, V. Jurgenson, A. Kolker, K. Conko, E. Landa, B. Panov, Y. Panov, H. Xu
2008, Journal of Occupational and Environmental Hygiene (5) 483-489
This study evaluates biomarkers of occupational mercury exposure among workers at a mercury recycling operation in Gorlovka, Ukraine. The 29 study participants were divided into three occupational categories for analysis: (1) those who worked in the mercury recycling operation (Group A, n = 8), (2) those...
Relative importance of natural disturbances and habitat degradation on snail kite population dynamics
J. Martin, W.M. Kitchens, Christopher E. Cattau, M.K. Oli
2008, Endangered Species Research (6) 25-39
Natural disturbances and habitat degradation are major factors influencing the dynamics and persistence of many wildlife populations, yet few large-scale studies have explored the relative influence of these factors on the dynamics and persistence of animal populations. We used longterm demographic data and matrix population models to examine the potential...
Sources, transformations, and hydrological processes that control stream nitrate and dissolved organic matter concentrations during snowmelt in an upland forest
Stephen D. Sebestyen, Elizabeth W. Boyer, James B. Shanley, Carol Kendall, Daniel H. Doctor, George R. Aiken, Nobuhito Ohte
2008, Water Resources Research (44)
We explored catchment processes that control stream nutrient concentrations at an upland forest in northeastern Vermont, USA, where inputs of nitrogen via atmospheric deposition are among the highest in the nation and affect ecosystem functioning. We traced sources of water, nitrate, and dissolved organic matter (DOM) using stream water samples...
Evaporite-karst problems and studies in the USA
K.S. Johnson
2008, Conference Paper, Environmental Geology
Evaporites, including rock salt (halite) and gypsum (or anhydrite), are the most soluble among common rocks; they dissolve readily to form the same types of karst features that commonly are found in limestones and dolomites. Evaporites are present in 32 of the 48 contiguous states in USA, and they underlie...
Isotopic variations of dissolved copper and zinc in stream waters affected by historical mining
David M. Borrok, David Nimick, Richard B. Wanty, William I. Ridley
2008, Geochimica et Cosmochimica Acta (72) 329-344
Zinc and Cu play important roles in the biogeochemistry of natural systems, and it is likely that these interactions result in mass-dependent fractionations of their stable isotopes. In this study, we examine the relative abundances of dissolved Zn and Cu isotopes in a variety of stream waters draining six historical...
Numerical simulation of the paleohydrology of glacial Lake Oshkosh, eastern Wisconsin, USA
J.A. Clark, K.M. Befus, T.S. Hooyer, P.W. Stewart, T.D. Shipman, C.T. Gregory, D.J. Zylstra
2008, Quaternary Research (69) 117-129
Proglacial lakes, formed during retreat of the Laurentide ice sheet, evolved quickly as outlets became ice-free and the earth deformed through glacial isostatic adjustment. With high-resolution digital elevation models (DEMs) and GIS methods, it is possible to reconstruct the evolution of surface hydrology. When a DEM deforms through time as...
A comparative analysis of simulated and observed landslide locations triggered by Hurricane Camille in Nelson County, Virginia
M.M. Morrissey, G. F. Wieczorek, B. A. Morgan
2008, Hydrological Processes (22) 524-531
In 1969, Nelson County, Virginia received up to 71 cm of rain within 12 h starting at 7 p.m. on August 19. The total rainfall from the storm exceeded the 1000-year return period in the region. Several thousands of landslides were induced by rainfall associated with Hurricane Camille causing fatalities...
Potential for 4-n-nonylphenol biodegradation in stream sediments
P. M. Bradley, L. B. Barber, D.W. Kolpin, P.B. McMahon, F. H. Chapelle
2008, Environmental Toxicology and Chemistry (27) 260-265
The potential for in situ biodegradation of 4-nonylphenol (4-NP) was investigated in three hydrologically distinct streams impacted by wastewater treatment plants (WWTPs) in the United States. Microcosms were prepared with sediments from each site and amended with [U-ring-14C]4-n-nonylphenol (4-n-NP) as a model test substrate. Microcosms prepared with sediment collected upstream...
Understanding the relationship between audiomagnetotelluric data and models, and borehole data in a hydrological environment
D.K. McPhee, L. Pellerin
2008, Conference Paper, SEG Technical Program Expanded Abstracts
Audiomagnetotelluric (AMT) data and resulting models are analyzed with respect to geophysical and geological borehole logs in order to clarify the relationship between the two methodologies of investigation of a hydrological environment. Several profiles of AMT data collected in basins in southwestern United States are being used for groundwater exploration...
Mathematical models frame environmental dispute [Review of the article Useless arithmetic: Ten points to ponder when using mathematical models in environmental decision making]
Berton Lee Lamb, Nina Burkardt
2008, Public Administration Review (68) 55-60
When Linda Pilkey- Jarvis and Orrin Pilkey state in their article, "Useless Arithmetic," that "mathematical models are simplified, generalized representations of a process or system," they probably do not mean to imply that these models are simple. Rather, the models are simpler than nature and that is the heart of...
NMR and mass spectrometry of phosphorus in wetlands
H. El-Rifai, M. Heerboth, T.E. Gedris, S. Newman, W. Orem, W.T. Cooper
2008, European Journal of Soil Science (59) 517-525
There is at present little information on the long-term stability of phosphorus sequestered in wetlands. Phosphorus sequestered during high loading periods may be relatively unstable and easily remobilized following changes in nutrient status or hydrological regime, but the chemical forms of sequestered phosphorus that do remobilize are largely unknown at...
A multi-residue method for the analysis of pesticides and pesticide degradates in water using HLB solid-phase extraction and gas chromatography-ion trap mass spectrometry
M.L. Hladik, K.L. Smalling, K.M. Kuivila
2008, Bulletin of Environmental Contamination and Toxicology (80) 139-144
A method was developed for the analysis of over 60 pesticides and degradates in water by HLB solid-phase extraction and gas-chromatography/mass spectrometry. Method recoveries and detection limits were determined using two surface waters with different dissolved organic carbon (DOC) concentrations. In the lower DOC water, recoveries and detection limits...
Water-quality monitoring and process understanding in support of environmental policy and management
N.E. Peters
2008, Conference Paper, IAHS-AISH Publication
The quantity and quality of freshwater at any point on the landscape reflect the combined effects of many processes operating along hydrological pathways within a drainage basin/watershed/catchment. Primary drivers for the availability of water are landscape changes and patterns, and the processes affecting the timing, magnitude, and intensity of precipitation,...
