Stream ecosystem response to limestone treatment in acid impacted watersheds of the allegheny plateau
S.E. McClurg, J.T. Petty, P. M. Mazik, J.L. Clayton
2007, Ecological Applications (17) 1087-1104
Restoration programs are expanding worldwide, but assessments of restoration effectiveness are rare. The objectives of our study were to assess current acid-precipitation remediation programs in streams of the Allegheny Plateau ecoregion of West Virginia (USA), identify specific attributes that could and could not be fully restored, and quantify temporal trends...
Regional magnetic anomalies, crustal strength, and the location of the northern Cordilleran fold-and-thrust belt
R. W. Saltus, T. L. Hudson
2007, Geology (35) 567-570
The northern Cordilleran fold-and-thrust belt in Canada and Alaska is at the boundary between the broad continental margin mobile belt and the stable North American craton. The fold-and-thrust belt is marked by several significant changes in geometry: cratonward extensions in the central Yukon Territory and northeastern Alaska are separated by...
Young cumulate complex beneath Veniaminof caldera, Aleutian arc, dated by zircon in erupted plutonic blocks
C. R. Bacon, T.W. Sison, F.K. Mazdab
2007, Geology (35) 491-494
Mount Veniaminof volcano, Alaska Peninsula, provides an opportunity to relate Quaternary volcanic rocks to a coeval intrusive complex. Veniaminof erupted tholeiitic basalt through dacite in the past ∼260 k.y. Gabbro, diorite, and miarolitic granodiorite blocks, ejected 3700 14C yr B.P. in the most recent...
A new comprehensive approach to characterizing carbonaceous aerosol with an application to wintertime Fresno, California PM2.5
P. Herckes, J.A. Leenheer, J.L. Collett Jr.
2007, Atmospheric Chemistry and Physics Discussions (7) 8423-8453
Fine particulate matter (PM2.5) samples were collected during a three week winter period in Fresno (CA). A composite sample was characterized by isolating several distinct fractions and characterizing them by infrared and nuclear magnetic resonance (NMR) spectroscopy. More than 80% of the organic matter in the aerosol samples was recovered...
Potential strategies for recovery of lake whitefish and lake herring stocks in eastern Lake Erie
K. Oldenburg, M.A. Stapanian, P.A. Ryan, E. Holm
2007, Journal of Great Lakes Research (33) 46-58
Lake Erie sustained large populations of ciscoes (Salmonidae: Coregoninae) 120 years ago. By the end of the 19th century, abundance of lake whitefish (Coregonus clupeaformis) had declined drastically. By 1925, the lake herring (a cisco) population (Coregonus artedii) had collapsed, although a limited lake herring fishery persisted in the eastern basin until...
Coupling contaminants with demography: Effects of lead and selenium in Pacific common eiders
H.M. Wilson, Paul L. Flint, A.N. Powell
2007, Environmental Toxicology and Chemistry (26) 1410-1417
We coupled intensive population monitoring with collection of blood samples from 383 nesting Pacific common eiders (Somateria mollisima v-nigrum) at two locations in Alaska (USA) from 2002 to 2004. We investigated annual, geographic, and within-season variation in blood concentrations of lead and selenium; compared exposure patterns with sympatrically nesting spectacled...
Seasonal variations in modern speleothem calcite growth in Central Texas, U.S.A
J.L. Banner, A. Guilfoyle, E.W. James, L.A. Stern, M. Musgrove
2007, Journal of Sedimentary Research (77) 615-622
Variations in growth rates of speleothem calcite have been hypothesized to reflect changes in a range of paleoenvironmental variables, including atmospheric temperature and precipitation, drip-water composition, and the rate of soil CO2 delivery to the subsurface. To test these hypotheses, we quantified growth rates of modern speleothem calcite on artificial...
Balancing data sharing requirements for analyses with data sensitivity
C. S. Jarnevich, J.J. Graham, G.J. Newman, A.W. Crall, T.J. Stohlgren
2007, Biological Invasions (9) 597-599
Data sensitivity can pose a formidable barrier to data sharing. Knowledge of species current distributions from data sharing is critical for the creation of watch lists and an early warning/rapid response system and for model generation for the spread of invasive species. We have created an on-line system to synthesize...
Factors associated with sources, transport, and fate of volatile organic compounds and their mixtures in aquifers of the United States
P. J. Squillace, M.J. Moran
2007, Environmental Science & Technology (41) 2123-2130
Factors associated with sources, transport, and fate of volatile organic compounds (VOCs) in groundwater from aquifers throughout the United States were evaluated using statistical methods. Samples were collected from 1631 wells throughout the conterminous United States between 1996 and 2002 as part of the National Water-Quality Assessment (NAWQA) Program of...
Detection, attribution, and sensitivity of trends toward earlier streamflow in the Sierra Nevada
E.P. Maurer, I.T. Stewart, Celine Bonfils, P. B. Duffy, D. Cayan
2007, Journal of Geophysical Research D: Atmospheres (112)
Observed changes in the timing of snowmelt dominated streamflow in the western United States are often linked to anthropogenic or other external causes. We assess whether observed streamflow timing changes can be statistically attributed to external forcing, or whether they still lie within the bounds of natural (internal) variability for...
Evidence of feline immunodeficiency virus, feline leukemia virus, and Toxoplasma gondii in feral cats on Mauna Kea, Hawaii
R.M. Danner, Dan M. Goltz, S.C. Hess, P.C. Banko
2007, Journal of Wildlife Diseases (43) 315-318
We determined prevalence to feline immunodeficiency virus (FIV) antibodies, feline leukemia virus (FeLV) antigen, and Toxoplasma gondii antibodies in feral cats (Felis catus) on Mauna Kea Hawaii from April 2002 to May 2004. Six of 68 (8.8%) and 11 of 68 (16.2%) cats were antibody positive to FIV and antigen...
Hydrology and water quality in two mountain basins of the northeastern US: Assessing baseline conditions and effects of ski area development
B. Wemple, J. Shanley, J. Denner, D. Ross, K. Mills
2007, Conference Paper, Hydrological Processes
Mountain regions throughout the world face intense development pressures associated with recreational and tourism uses. Despite these pressures, much of the research on bio-geophysical impacts of humans in mountain regions has focused on the effects of natural resource extraction. This paper describes findings from the first 3 years of a...
The role of natural vegetative disturbance in determining stream reach characteristics in central Idaho and western Montana
B.B. Roper, B. Jarvis, J. L. Kershner
2007, Northwest Science (81) 224-238
We evaluated the relationship between natural vegetative disturbance and changes in stream habitat and macroinvertebrate metrics within 33 randomly selected minimally managed watersheds in central Idaho and western Montana. Changes in stream reach conditions were related to vegetative disturbance for the time periods from 1985 to 1993 and 1993 to...
Groundwater noble gas, age, and temperature signatures in an Alpine watershed: Valuable tools in conceptual model development
Andrew H. Manning, Jonathan S. Caine
2007, Water Resources Research (43)
Bedrock groundwater in alpine watersheds is poorly understood, mainly because of a scarcity of wells in alpine settings. Groundwater noble gas, age, and temperature data were collected from springs and wells with depths of 3–342 m in Handcart Gulch, an alpine watershed in Colorado. Temperature profiles indicate active groundwater circulation...
Molecular analysis of fungal communities and laccase genes in decomposing litter reveals differences among forest types but no impact of nitrogen deposition
C.B. Blackwood, M. P. Waldrop, D.R. Zak, R. L. Sinsabaugh
2007, Environmental Microbiology (9) 1306-1316
The fungal community of the forest floor was examined as the cause of previously reported increases in soil organic matter due to experimental N deposition in ecosystems producing predominantly high-lignin litter, and the opposite response in ecosystems producing low-lignin litter. The mechanism proposed to explain this phenomenon was that white-rot...
Chemical contaminants in fish feeds used in federal salmonid hatcheries in the USA
A.G. Maule, A.L. Gannam, J.W. Davis
2007, Chemosphere (67) 1308-1315
Recent studies have demonstrated that fish feeds contain significant concentrations of contaminants, many of which can bioaccumulate and bioconcentrate in fish. Organochlorine (OC) contaminants are present in the fish oils and fish meals used in feed manufacture, and some researchers speculate that all fish feeds contain measurable levels of some...
A field assessment of the value of steady shape hydraulic tomography for characterization of aquifer heterogeneities
Geoffrey C. Bohling, James J. Butler Jr., Xiaoyong Zhan, Michael D. Knoll
2007, Water Resources Research (43)
Hydraulic tomography is a promising approach for obtaining information on variations in hydraulic conductivity on the scale of relevance for contaminant transport investigations. This approach involves performing a series of pumping tests in a format similar to tomography. We present a field‐scale assessment of hydraulic tomography in a porous aquifer,...
Luminescence ages for alluvial-fan deposits in Southern Death Valley: Implications for climate-driven sedimentation along a tectonically active mountain front
M.F. Sohn, S. A. Mahan, J.R. Knott, D.D. Bowman
2007, Quaternary International (166) 49-60
Controversy exists over whether alluvial-fan sedimentation along tectonically active mountain fronts is driven by climatic changes or tectonics. Knowing the age of sedimentation is the key to understanding the relationship between sedimentation and its cause. Alluvial-fan deposits in Death Valley and throughout the arid southwestern United States have long been...
Biomarkers of metals exposure in fish from lead-zinc mining areas of Southeastern Missouri, USA
C. J. Schmitt, J.J. Whyte, A.P. Roberts, M.L. Annis, T.W. May, D. E. Tillitt
2007, Ecotoxicology and Environmental Safety (67) 31-47
The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30 y under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91;...
Did debris-covered glaciers serve as pleistocene refugia for plants? A new hypothesis derived from observations of recent plant growth on glacier surfaces
T. Fickert, D. Friend, F. Gruninger, B. Molnia, M. Richter
2007, Arctic, Antarctic, and Alpine Research (39) 245-257
This study proposes a new hypothesis: Debris-covered glaciers served as Pleistocene biological refugia. This is based on detailed studies of vascular plant growth on six debris-mantled glaciers, literally around the world, as well as many casual observations also across the globe. We find that such glaciers are quite common and...
Assessing the concentration, speciation, and toxicity of dissolved metals during mixing of acid-mine drainage and ambient river water downstream of the Elizabeth Copper Mine, Vermont, USA
Laurie S. Balistrieri, R.R. Seal II, N.M. Piatak, B. Paul
2007, Applied Geochemistry (22) 930-952
The authors determine the composition of a river that is impacted by acid-mine drainage, evaluate dominant physical and geochemical processes controlling the composition, and assess dissolved metal speciation and toxicity using a combination of laboratory, field and modeling studies. Values of pH increase from 3.3 to 7.6 and the sum...
First record of ithytrichia (Trichoptera: Hydroptilidae) in Michigan, U.S.A.
J.M. Craig, M.A. Chriscinske
2007, Entomological News (118) 313-314
[No abstract available]...
Variation in winter diet of southern Beaufort Sea polar bears inferred from stable isotope analysis
T.W. Bentzen, Erich H. Follmann, Steven C. Amstrup, G.S. York, M. J. Wooller, T. M. O'Hara
2007, Canadian Journal of Zoology (85) 596-608
Ringed seals (Phoca hispida Schreber, 1775 = Pusa hispida (Schreber, 1775)) and bearded seals (Erignathus barbatus (Erxleben, 1777)) represent the majority of the polar bear (Ursus maritimus Phipps, 1774) annual diet. However, remains of lower trophic level bowhead whales (Balaena mysticetus L., 1758) are available in the southern Beaufort Sea and their dietary contribution to polar...
Surface temperature patterns in complex terrain: Daily variations and long-term change in the central Sierra Nevada, California
J.D. Lundquist, D.R. Cayan
2007, Journal of Geophysical Research D: Atmospheres (112)
A realistic description of how temperatures vary with elevation is crucial for ecosystem studies and for models of basin-scale snowmelt and spring streamflow. This paper explores surface temperature variability using temperature data from an array of 37 sensors, called the Yosemite network, which traverses both slopes of the Sierra Nevada...
A closer look at water-related geologic activity on Mars
Alfred S. McEwen, C.J. Hansen, W.A. Delamere, E. M. Eliason, Kenneth E. Herkenhoff, Laszlo P. Keszthelyi, V. C. Gulick, Randolph L. Kirk, M. T. Mellon, J. A. Grant, N. Thomas, C.M. Weitz, S. W. Squyres, N.T. Bridges, S.L. Murchie, F. Seelos, K. Seelos, C.H. Okubo, M.P. Milazzo, L.L. Tornabene, W.L. Jaeger, S. Byrne, P.S. Russell, J.L. Griffes, S. Martinez-Alonso, A. Davatzes, F. C. Chuang, B.J. Thomson, K.E. Fishbaugh, C. M. Dundas, K.J. Kolb, M. E. Banks, J.J. Wray
2007, Science (317) 1706-1709
Water has supposedly marked the surface of Mars and produced characteristic landforms. To understand the history of water on Mars, we take a close look at key locations with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter, reaching fine spatial scales of 25 to 32 centimeters per...
