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...
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...
Structure of the California Coast Ranges and San Andreas Fault at SAFOD from seismic waveform inversion and reflection imaging
F. Bleibinhaus, J.A. Hole, T. Ryberg, G. S. Fuis
2007, Journal of Geophysical Research B: Solid Earth (112)
[1] A seismic reflection and refraction survey across the San Andreas Fault (SAF) near Parkfield provides a detailed characterization of crustal structure across the location of the San Andreas Fault Observatory at Depth (SAFOD). Steep-dip prestack migration and frequency domain acoustic waveform tomography were applied to...
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...
Suspended sediment transport in an ephemeral stream following wildfire
D.V. Malmon, Steven L. Reneau, D. Katzman, A. Lavine, J. Lyman
2007, Journal of Geophysical Research F: Earth Surface (112)
We examine the impacts of a stand-clearing wildfire on the characteristics and magnitude of suspended sediment transport in ephemeral streams draining the burn area. We report the results of a monitoring program that includes 2 years of data prior to the Cerro Grande fire in...
Environmental and ecological conditions surrounding the production of large year classes of walleye (Sander vitreus) in Saginaw Bay, Lake Huron
D.G. Fielder, J.S. Schaeffer, M.V. Thomas
2007, Journal of Great Lakes Research (33) 118-132
The Saginaw Bay walleye population (Sander vitreus) has not fully recovered from a collapse that began in the 1940s and has been dependent on stocking with only limited natural reproduction. Beginning in 2003, and through at least 2005, reproductive success of walleye surged to unprecedented levels. The increase was concurrent...
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...
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,...
Eogenetic karst hydrology: Insights from the 2004 hurricanes, peninsular Florida
L.J. Florea, H. Leonard Vacher
2007, Ground Water (45) 439-446
Eogenetic karst lies geographically and temporally close to the depositional environment of limestone in warm marine water at low latitude, in areas marked by midafternoon thunderstorms during a summer rainy season. Spring hydrographs from such an environment in north-central Florida are characterized by smooth, months-long, seasonal maxima. The passage of...
Rapid plant diversity assessment using a pixel nested plot design: A case study in Beaver Meadows, Rocky Mountain National Park, Colorado, USA
M. A. Kalkhan, E.J. Stafford, T.J. Stohlgren
2007, Diversity and Distributions (13) 379-388
Geospatial statistical modelling and thematic maps have recently emerged as effective tools for the management of natural areas at the landscape scale. Traditional methods for the collection of field data pertaining to questions of landscape were developed without consideration for the parameters of these applications. We introduce an alternative field...
A simple model for the spatially-variable coastal response to hurricanes
H.F. Stockdon, A. H. Sallenger Jr., R.A. Holman, P.A. Howd
2007, Marine Geology (238) 1-20
The vulnerability of a beach to extreme coastal change during a hurricane can be estimated by comparing the relative elevations of storm-induced water levels to those of the dune or berm. A simple model that defines the coastal response based on these elevations was used to hindcast the potential impact...
Species richness and soil properties in Pinus ponderosa forests: A structural equation modeling analysis
D.C. Laughlin, S.R. Abella, W.W. Covington, J.B. Grace
2007, Journal of Vegetation Science (18) 231-242
Question: How are the effects of mineral soil properties on understory plant species richness propagated through a network of processes involving the forest overstory, soil organic matter, soil nitrogen, and understory plant abundance? Location: North-central Arizona, USA. Methods: We sampled 75 0.05-ha plots across a broad soil gradient in a...
Population-specific demographic estimates provide insights into declines of Lark Buntings (Calamospiza melanocorys)
A. A. Yackel Adams, S. K. Skagen, J. A. Savidge
2007, The Auk (124) 578-593
Many North American prairie bird populations have recently declined, and the causes of these declines remain largely unknown. To determine whether population limitation occurs during breeding, we evaluated the stability of a population of prairie birds using population-specific values for fecundity and postfledging survival. During 2001-2003, we radiomarked 67 female...
Lead (Pb) in old Antarctic ice: Some from dust, some from other sources
T. Hinkley
2007, Geophysical Research Letters (34)
Recently published data on amounts and isotopic compositions of lead (Pb) and on amounts of mineral dust in pre-industrial Antarctic ice can be further interpreted by means of simple calculations. These show that two distinct types of Pb were provided by the atmosphere to the continent in varying proportions during...
On the formation and structure of rare-earth element complexes in aqueous solutions under hydrothermal conditions with new data on gadolinium aqua and chloro complexes
Robert A. Mayanovic, Alan J. Anderson, William A. Bassett, I.-M. Chou
2007, Chemical Geology (239) 266-283
Synchrotron X-ray spectroscopy experiments were made on the Gd(III) aqua and chloro complexes in low pH aqueous solutions at temperatures ranging from 25 to 500????C and at pressures up to 480??MPa using a hydrothermal diamond anvil cell. Analysis of fluorescence Gd L3-edge X-ray absorption fine structure (XAFS) spectra measured from...
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...
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]...
Estimation of evapotranspiration by reed canarygrass using field observations and model simulations
K. E. Schilling, James R. Kiniry
2007, Journal of Hydrology (337) 356-363
Reed canarygrass (Phalaris arundinacea) commonly invades meadow wetlands, effectively dominating water use and outcompeting native plants. Objectives of this study were to (i) estimate daily, seasonal and annual water use by reed canarygrass using shallow water table fluctuations; and (ii) calibrate the ALMANAC (Agricultural Land Management Alternative with Numerical Assessment...
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...
Improved wetland remote sensing in Yellowstone National Park using classification trees to combine TM imagery and ancillary environmental data
C. Wright, Alisa L. Gallant
2007, Remote Sensing of Environment (107) 582-605
The U.S. Fish and Wildlife Service uses the term palustrine wetland to describe vegetated wetlands traditionally identified as marsh, bog, fen, swamp, or wet meadow. Landsat TM imagery was combined with image texture and ancillary environmental data to model probabilities of palustrine wetland occurrence in Yellowstone National Park using classification...
Mangrove removal in the belize cays: effects on mangrove-associated fish assemblages in the intertidal and subtidal
D.S. Taylor, E.A. Reyier, W.P. Davis, C.C. McIvor
2007, Bulletin of Marine Science (80) 879-890
We investigated the effects of mangrove cutting on fish assemblages in Twin Cays, Belize, in two habitat types. We conducted visual censuses at two sites in adjoining undisturbed/disturbed (30%–70% of shoreline fringe removed) sub-tidal fringing Rhizophora mangle Linnaeus, 1753. Observers recorded significantly more species and individuals in undisturbed sites, especially...
Temperature-mediated differences in bacterial kidney disease expression and survival in Renibacterium salmoninarum-challenged bull trout and other salmonids
D.T. Jones, C.M. Moffitt, K.K. Peters
2007, North American Journal of Fisheries Management (27) 695-706
Resource managers considering restoration and reconnection of watersheds to protect and enhance threatened populations of bull trout Salvelinus confluentus have little information about the consequences of bacterial kidney disease (BKD) caused by Renibacterium salmoninarum. To better understand the response of bull trout to R. salmoninarum challenge, we conducted several laboratory...
Diet and prey selection by Lake Superior lake trout during springs 1986-2001
B.A. Ray, T.R. Hrabik, M.P. Ebener, O. T. Gorman, D.R. Schreiner, S.T. Schram, S.P. Sitar, W.P. Mattes, C.R. Bronte
2007, Journal of Great Lakes Research (33) 104-113
We describe the diet and prey selectivity of lean (Salvelinus namaycush namaycush) and siscowet lake trout (S. n. siscowet) collected during spring (April–June) from Lake Superior during 1986–2001. We estimated prey selectivity by comparing prey numerical abundance estimates from spring bottom trawl surveys and lake trout diet information in similar...
