Fate of geothermal mercury from Yellowstone National Park in the Madison and Missouri Rivers, USA
David A. Nimick, Rodney R. Caldwell, Donald R. Skaar, Trevor M. Selch
2013, Science of the Total Environment (443) 40-54
Mercury is a worldwide contaminant derived from natural and anthropogenic sources. River systems play a key role in the transport and fate of Hg because they drain widespread areas affected by aerial Hg deposition, transport Hg away from point sources, and are sites of Hg biogeochemical cycling and bioaccumulation. The...
Contaminants in stream sediments from seven United States metropolitan areas: part II—sediment toxicity to the amphipod Hyalella azteca and the midge Chironomus dilutus
Nile E. Kemble, Douglas K. Hardesty, Christopher G. Ingersoll, James L. Kunz, Paul K. Sibley, Daniel L. Calhoun, Robert J. Gilliom, Kathryn Kuivila, Lisa H. Nowell, Patrick W. Moran
2013, Archives of Environmental Contamination and Toxicology (64) 52-64
Relationships between sediment toxicity and sediment chemistry were evaluated for 98 samples collected from seven metropolitan study areas across the United States. Sediment-toxicity tests were conducted with the amphipod Hyalella azteca (28 day exposures) and with the midge Chironomus dilutus (10 day exposures). Overall, 33 % of the samples were...
Toxicity of sediments potentially contaminated by coal mining and natural gas extraction to unionid mussels and commonly tested benthic invertebrates
Ning Wang, Christopher G. Ingersoll, James L. Kunz, William G. Brumbaugh, Cindy M. Kane, R. Brian Evans, Steven Alexander, Craig Walker, Steve Bakaletz
2013, Environmental Toxicology and Chemistry (32) 207-221
Sediment toxicity tests were conducted to assess potential effects of contaminants associated with coal mining or natural gas extraction activities in the upper Tennessee River basin and eastern Cumberland River basin in the United States. Test species included two unionid mussels (rainbow mussel, Villosa iris, and wavy-rayed lampmussel, Lampsilis fasciola,...
Assessing the relative bioavailability of DOC in regional groundwater systems
Francis H. Chapelle, Paul M. Bradley, Celeste A. Journey, Peter B. McMahon
2013, Ground Water (51) 363-372
It has been hypothesized that the degree to which a hyperbolic relationship exists between concentrations of dissolved organic carbon (DOC) and dissolved oxygen (DO) in groundwater may indicate the relative bioavailability of DOC. This hypothesis was examined for 73 different regional aquifers of the United States using 7745 analyses of...
Warming and the dependence of limber pine (Pinus flexilis) establishment on summer soil moisture within and above its current elevation range
Andrew B. Moyes, Cristina Castanha, Matthew J. Germino, Lara M. Kueppers
2013, Oecologia (171) 271-282
Continued changes in climate are projected to alter the geographic distributions of plant species, in part by affecting where individuals can establish from seed. We tested the hypothesis that warming promotes uphill redistribution of subalpine tree populations by reducing cold limitation at high elevation and enhancing drought stress at low...
Global change effects on Bromus tectorum L. (Poaceae) at its high-elevation range margin
Amy L. Concilio, Michael E. Loik, Jayne Belnap
2013, Global Change Biology (19) 161-172
Global change is likely to affect invasive species distribution, especially at range margins. In the eastern Sierra Nevada, California, USA, the invasive annual grass, Bromus tectorum, is patchily distributed and its impacts have been minimal compared with other areas of the Intermountain West. We used a series of in situ...
Phosphorus losses from agricultural watersheds in the Mississippi Delta
Yongping Yuan, Martin A. Locke, Ronald L. Bingner, Richard A. Rebich
2013, Journal of Environmental Management (115) 14-20
Phosphorus (P) loss from agricultural fields is of environmental concern because of its potential impact on water quality in streams and lakes. The Mississippi Delta has long been known for its fish productivity and recreational value, but high levels of P in fresh water can lead to algal blooms that...
Effects of road decommissioning on carbon stocks, losses, and emissions in north coastal California
Mary Ann Madej, Joseph Seney, Philip van Mantgem
2013, Restoration Ecology (21) 439-446
During the last 3 decades, many road removal projects have been implemented on public and private lands in the United States to reduce erosion and other impacts from abandoned or unmaintained forest roads. Although effective in decreasing sediment production from roads, such activities have a carbon (C) cost as well...
Cancer risk from incidental ingestion exposures to PAHs associated with coal-tar-sealed pavement
E. Spencer Williams, Barbara Mahler, Peter C. Van Metre
2013, Environmental Science & Technology (47) 1101-1109
Recent (2009–10) studies documented significantly higher concentrations of polycyclic aromatic hydrocarbons (PAHs) in settled house dust in living spaces and soil adjacent to parking lots sealed with coal-tar-based products. To date, no studies have examined the potential human health effects of PAHs from these products in dust and soil. Here...
Thermokarst lakes, drainage, and drained basins
Guido Grosse, Benjamin M. Jones, Christopher D. Arp
John F. Shroder, editor(s)
2013, Book chapter, Treatise on Geomorphology
Thermokarst lakes and drained lake basins are widespread in Arctic and sub-Arctic permafrost lowlands with ice-rich sediments. Thermokarst lake formation is a dominant mode of permafrost degradation and is linked to surface disturbance, subsequent melting of ground ice, surface subsidence, water impoundment, and positive feedbacks between lake growth and permafrost...
Influence of dietary carbon on mercury bioaccumulation in streams of the Adirondack Mountains of New York and the Coastal Plain of South Carolina, USA
Karen Riva-Murray, Paul M. Bradley, Lia C. Chasar, Daniel T. Button, Mark E. Brigham, Barbara C. Scudder Eikenberry, Celeste A. Journey, Michelle A. Lutz
2013, Ecotoxicology (22) 60-71
We studied lower food webs in streams of two mercury-sensitive regions to determine whether variations in consumer foraging strategy and resultant dietary carbon signatures accounted for observed within-site and among-site variations in consumer mercury concentration. We collected macroinvertebrates (primary consumers and predators) and selected forage fishes from three sites in...
An alternative process model of preferential contaminant travel times in the unsaturated zone: Application to Rainier Mesa and Shoshone Mountain, Nevada
Brian A. Ebel, John R. Nimmo
2013, Environmental Modeling & Assessment (18) 345-363
Simulating contaminant transport in unsaturated zones with sparse hydraulic property information is a difficult, yet common, problem. When contaminant transport may occur via preferential flow, simple modeling approaches can provide predictions of interest, such as the first arrival of contaminant, with minimal site characterization. The conceptual model for unsaturated zone...
The response of Lake Tahoe to climate change
G.B. Sahoo, S.G. Schladow, J.E. Reuter, R. Coats, M. Dettinger, J. Riverson, B. Wolfe, M. Costa-Cabral
2013, Climatic Change (116) 71-95
Meteorology is the driving force for lake internal heating, cooling, mixing, and circulation. Thus continued global warming will affect the lake thermal properties, water level, internal nutrient loading, nutrient cycling, food-web characteristics, fish-habitat, aquatic ecosystem, and other important features of lake limnology. Using a 1-D numerical model - the Lake...
Small-scale turbidity currents in a big submarine canyon
Jingping Xu, James P. Barry, Charles K. Paull
2013, Geology Today (41) 143-146
Field measurements of oceanic turbidity currents, especially diluted currents, are extremely rare. We present a dilute turbidity current recorded by instrumented moorings 14.5 km apart at 1300 and 1860 m water depth. The sediment concentration within the flow was 0.017%, accounting for 18 cm/s gravity current speed due to density...
The interactive effects of excess reactive nitrogen and climate change on aquatic ecosystems and water resources of the United States
Jill Baron, E. K. Hall, B. T. Nolan, J. C. Finlay, E. S. Bernhardt, J. A. Harrison, F. Chan, E.W. Boyer
2013, Biogeochemistry (114) 71-92
Nearly all freshwaters and coastal zones of the US are degraded from inputs of excess reactive nitrogen (Nr), sources of which are runoff, atmospheric N deposition, and imported food and feed. Some major adverse effects include harmful algal blooms, hypoxia of fresh and coastal waters, ocean acidification, long-term harm to...
Sensitivity analysis of lake mass balance in discontinuous permafrost: the example of disappearing Twelvemile Lake, Yukon Flats, Alaska (USA)
S.M. Jepsen, C.I. Voss, Michelle Ann Walvoord, J.R. Rose, B. J. Minsley, B. D. Smith
2013, Hydrogeology Journal (21) 185-200
Many lakes in northern high latitudes have undergone substantial changes in surface area over the last four decades, possibly as a result of climate warming. In the discontinuous permafrost of Yukon Flats, interior Alaska (USA), these changes have been non-uniform across adjacent watersheds, suggesting local controls on lake water budgets....
Effects of linking a soil-water-balance model with a groundwater-flow model
Jennifer S. Stanton, Derek W. Ryter, Steven M. Peterson
2013, Ground Water Journal (51) 613-622
A previously published regional groundwater-flow model in north-central Nebraska was sequentially linked with the recently developed soil-water-balance (SWB) model to analyze effects to groundwater-flow model parameters and calibration results. The linked models provided a more detailed spatial and temporal distribution of simulated recharge based on hydrologic processes, improvement of simulated...
Environmental factors regulating the recruitment of walleye Sander vitreus and white bass Morone chrysops in irrigation reservoirs
Jason A. DeBoer, Kevin L. Pope, Keith D. Koupal
2013, Ecology of Freshwater Fish (22) 43-54
Understanding the environmental factors that regulate fish recruitment is essential for effective management of fisheries. Generally, first-year survival, and therefore recruitment, is inherently less consistent in systems with high intra- and interannual variability. Irrigation reservoirs display sporadic patterns of annual drawdown, which can pose a substantial challenge to recruitment of...
Trends and shifts in streamflow in Hawaii, 1913-2008
Maoya Bassiouni, Delwyn S. Oki
2013, Hydrological Processes (27) 1484-1500
This study addresses a need to document changes in streamflow and base flow (groundwater discharge to streams) in Hawai'i during the past century. Statistically significant long-term (1913-2008) downward trends were detected (using the nonparametric Mann-Kendall test) in low-streamflow and base-flow records. These long-term downward trends are likely related to a...
An 80-year record of sediment quality in the lower Mississippi River
Peter C. Van Metre, Arthur J. Horowitz
2013, Hydrological Processes (27) 2438-2448
In 1937, the US Army Corps of Engineers cut through the "neck" of a large meander on the lower Mississippi River (below the confluence with the Ohio River) forming the Caulk Neck cutoff and creating Lake Whittington, a 26-km long oxbow lake, in northern Mississippi. Since 1938, seasonal flooding and...
Intra- and inter-basin mercury comparisons: Importance of basin scale and time-weighted methylmercury estimates
Paul M. Bradley, Celeste A. Journey, Mark E. Bringham, Douglas A. Burns, Daniel T. Button, Karen Riva-Murray
2013, Environmental Pollution (172) 42-52
To assess inter-comparability of fluvial mercury (Hg) observations at substantially different scales, Hg concentrations, yields, and bivariate-relations were evaluated at nested-basin locations in the Edisto River, South Carolina and Hudson River, New York. Differences between scales were observed for filtered methylmercury (FMeHg) in the Edisto (attributed to wetland coverage differences)...
Gonadal abnormalities in frogs (Lithobates spp.) collected from managed wetlands in an agricultural region of Nebraska, USA
Diana M. Papoulias, Matt S. Schwarz, Lourdes Mena
2013, Environmental Pollution (172) 1-8
Nebraska's Rainwater Basin (RWB) provides important wetland habitat for North American migratory birds. Concern exists that pesticide and nutrient runoff from surrounding row-crops enters wetlands degrading water quality and adversely affecting birds and wildlife. Frogs may be especially vulnerable. Plains leopard (Lithobates blairi) metamorphs from RWB wetlands with varying concentrations...
The role of fire on soil mounds and surface roughness in the Mojave Desert
Christopher E. Soulard, Todd C. Esque, David R. Bedford, Sandra Bond
2013, Earth Surface Processes and Landforms (38) 111-121
A fundamental question in arid land management centers on understanding the long-term effects of fire on desert ecosystems. To assess the effects of fire on surface topography, soil roughness, and vegetation, we used terrestrial (ground-based) LiDAR to quantify the differences between burned and unburned surfaces by creating a series of...
Successional stage of biological soil crusts: an accurate indicator of ecohydrological condition
Jayne Belnap, Bradford P. Wilcox, Matthew V. Van Scoyoc, Susan L. Phillips
2013, Ecohydrology (6) 474-482
Biological soil crusts are a key component of many dryland ecosystems. Following disturbance, biological soil crusts will recover in stages. Recently, a simple classification of these stages has been developed, largely on the basis of external features of the crusts, which reflects their level of development (LOD). The classification system...
Shovelnose sturgeon spawning in relation to varying discharge treatments in a Missouri River tributary
B.J. Goodman, C.S. Guy, S.L. Camp, W.M. Gardner, K.M. Kappenman, M.A.H. Webb
2013, River Research and Applications (29) 1004-1015
Many lotic fish species use natural patterns of variation in discharge and temperature as spawning cues, and these natural patterns are often altered by river regulation. The effects of spring discharge and water temperature variation on the spawning of shovelnose sturgeon Scaphirhynchus platorynchus have not been well documented. From 2006...
