Community structure of fishes inhabiting aquatic refuges in a threatened Karst wetland and its implications for ecosystem management
Robert M. Kobza, J.C. Trexler, W.F. Loftus, S.A. Perry
2004, Biological Conservation (116) 153-165
We illustrate the importance of subsurface refuges for conservation of aquatic fauna with our studies of karstic wetlands in Everglades National Park, Florida, USA. Managers have proposed that water levels there should not fall more than 46 cm below ground level for more than 90 days annually. In four areas,...
Landscape responses of bats to habitat fragmentation in Atlantic forest of paraguay
P. M. Gorresen, M. R. Willig
2004, Journal of Mammalogy (85) 688-697
Understanding effects of habitat loss and fragmentation on populations or communities is critical to effective conservation and restoration. This is particularly important for bats because they provide vital services to ecosystems via pollination and seed dispersal, especially in tropical and subtropical habitats. Based on more than 1,000 h of survey...
Quantification of nearshore morphology based on video imaging
P. S. Alexander, R.A. Holman
2004, Marine Geology (208) 101-111
The Argus network is a series of video cameras with aerial views of beaches around the world. Intensity contrasts in time exposure images reveal areas of preferential breaking, which are closely tied to underlying bed morphology. This relationship was further investigated, including the effect of tidal elevation and wave height...
The effect of elevated methane pressure on methane hydrate dissociation
S. Circone, L.A. Stern, S. H. Kirby
2004, American Mineralogist (89) 1192-1201
Methane hydrate, equilibrated at P, T conditions within the hydrate stability field, was rapidly depressurized to 1.0 or 2.0 MPa and maintained at isobaric conditions outside its stability field, while the extent and rate of hydrate dissociation was measured at fixed, externally maintained temperatures between 250 and 288 K. The...
Geochemical control of microbial Fe(III) reduction potential in wetlands: Comparison of the rhizosphere to non-rhizosphere soil
J.V. Weiss, D. Emerson, J.P. Megonigal
2004, FEMS Microbiology Ecology (48) 89-100
We compared the reactivity and microbial reduction potential of Fe(III) minerals in the rhizosphere and non-rhizosphere soil to test the hypothesis that rapid Fe(III) reduction rates in wetland soils are explained by rhizosphere processes. The rhizosphere was defined as the area immediately adjacent to a root encrusted with Fe(III)-oxides or...
Spring onset in the Sierra Nevada: When is snowmelt independent of elevation?
J.D. Lundquist, D.R. Cayan, M. D. Dettinger
2004, Journal of Hydrometeorology (5) 327-342
Short-term climate and weather systems can have a strong influence on mountain snowmelt, sometimes overwhelming the effects of elevation and aspect. Although most years exhibit a spring onset that starts first at lowest and moves to highest elevations, in spring 2002, flow in a variety of streams...
Biomass accumulation and soil nitrogen availability in an 87-year-old Populus grandidentata chronosequence
L.L. White, D.R. Zak, B.V. Barnes
2004, Forest Ecology and Management (191) 121-127
The Upper Lake States region is marked by major disturbances of fire and logging over 100 years ago that created a landscape mosaic of early successional forests. Given the intimate link between soil N availability and forest growth in this region, it is important to understand how temporal changes in...
Evaluation of ultrastructure and random effects band recovery models for estimating relationships between survival and harvest rates in exploited populations
David L. Otis, Gary C. White
2004, Animal Biodiversity and Conservation (27) 157-173
Increased population survival rate after an episode of seasonal exploitation is considered a type of compensatory population response. Lack of an increase is interpreted as evidence that exploitation results in added annual mortality in the population. Despite its importance to management of exploited species, there are limited statistical techniques for...
Status of Ash Meadows speckled dace in Bradford Springs
T. Leavy, R.R McShane, K.M. Swaim, G.G. Scoppettone
2004, Report
No abstract available ...
The effects of wavelet compression on Digital Elevation Models (DEMs)
M. J. Oimoen
2004, Conference Paper, 2004 IEEE International Geoscience and Remote Sensing Symposium proceedings
This paper investigates the effects of lossy compression on floating-point digital elevation models using the discrete wavelet transform. The compression of elevation data poses a different set of problems and concerns than does the compression of images. Most notably, the usefulness of DEMs depends largely in the quality of their...
Landscape scale measures of steelhead (Oncorhynchus mykiss) bioenergetic growth rate potential in Lake Michigan and comparison with angler catch rates
T.O. Hook, E.S. Rutherford, Shannon J. Brines, C. A. Geddes, D.M. Mason, D.J. Schwab, G.W. Fleischer
2004, Journal of Great Lakes Research (30) 545-556
The relative quality of a habitat can influence fish consumption, growth, mortality, and production. In order to quantify habitat quality, several authors have combined bioenergetic and foraging models to generate spatially explicit estimates of fish growth rate potential (GRP). However, the capacity of GRP to reflect the spatial distributions of...
40Ar/39Ar dating of the eruptive history of Mount Erebus, Antarctica: Summit flows, tephra, and caldera collapse
C.J. Harpel, P.R. Kyle, R.P. Esser, W. C. McIntosh, D.A. Caldwell
2004, Bulletin of Volcanology (66) 687-702
Eruptive activity has occurred in the summit region of Mount Erebus over the last 95 ky, and has included numerous lava flows and small explosive eruptions, at least one plinian eruption, and at least one and probably two caldera-forming events. Furnace and laser step-heating 40Ar/39Ar ages have been determined for...
Illinois drainage water management demonstration project
D.J. Pitts, R. Cooke, P. J. Terrio
Cooke R.A., editor(s)
2004, Conference Paper, Proceedings of the 8th International Drainage Symposium - Drainage VIII
Due to naturally high water tables and flat topography, there are approximately 4 million ha (10 million ac) of farmland artificially drained with subsurface (tile) systems in Illinois. Subsurface drainage is practiced to insure trafficable field conditions for farm equipment and to reduce crop stress from excess water within the...
Study on geophone coupling and attenuating compensatory of low-depression velocity layer in desert area
Z. Shi, G. Tian, S. Dong, J. Xia, H. He
Chen C.Xia J., editor(s)
2004, Conference Paper, Progress in Environmental and Engineering Geophysics: Proceedings of the International Conference on Environmental and Engineering Geophysics, ICEEG 2004
In a desert area, it is difficult to couple geophones with dry sands. A low and depression velocity layer can seriously attenuate high frequency components of seismic data. Therefore, resolution and signal-to-noise (S/N) ratio of seismic data deteriorate. To enhance resolution and S/N ratio of seismic data, we designed a...
The Susitna Glacier thrust fault: Characteristics of surface ruptures on the fault that initiated the 2002 Denali fault earthquake
A. J. Crone, S. F. Personius, P. A. Craw, Peter J. Haeussler, L. A. Staft
2004, Bulletin of the Seismological Society of America (94) S5-S22
The 3 November 2002 Mw 7.9 Denali fault earthquake sequence initiated on the newly discovered Susitna Glacier thrust fault and caused 48 km of surface rupture. Rupture of the Susitna Glacier fault generated scarps on ice of the Susitna and West Fork glaciers and on tundra and surficial deposits along the southern...
Winter orographic precipitation ratios in the Sierra Nevada: Large-scale atmospheric circulations and hydrologic consequences
M. Dettinger, K. Redmond, D. Cayan
2004, Journal of Hydrometeorology (5) 1102-1116
The extent to which winter precipitation is orographically enhanced within the Sierra Nevada of California varies from storm to storm, and season to season, from occasions when precipitation rates at low and high altitudes are almost the same to instances when precipitation rates at middle elevations (considered...
Xenobiotic impact on Arctic char: Nutritional modulation and physiological consequences
A.G. Maule
2004, Report
No abstract available ...
Canada lynx Lynx canadensis habitat and forest succession in northern Maine, USA
C.L. Hoving, D.J. Harrison, W.B. Krohn, W.J. Jakubas, M.A. McCollough
2004, Wildlife Biology (10) 285-294
The contiguous United States population of Canada lynx Lynx canadensis was listed as threatened in 2000. The long-term viability of lynx populations at the southern edge of their geographic range has been hypothesized to be dependent on old growth forests; however, lynx are a specialist predator on snowshoe hare Lepus...
Concentrations of arsenic, cadmium, copper, lead, selenium, and zinc in fish from the Mississippi River Basin, 1995
Christopher J. Schmitt
2004, Environmental Monitoring and Assessment (90) 289-321
Fish were collected in late 1995 from 34 National Contaminant Biomonitoring Program (NCBP) stations and 12 National Water Quality Assessment Program (NAWQA) stations in the Mississippi River basin (MRB), and in late 1996 from a reference site in West Virginia. The NCBP sites represented key points (dams, tributaries, etc.) in...
Effects of Ichthyophonus on survival and reproductive success of Yukon River Chinook salmon. Final report for study 01-200
R. Kocan, P. Hershberger, J. Winton
2004, Report
No abstract available ...
Extracting transient Rayleigh wave and its application in detecting quality of highway roadbed
J. Liu, J. Xia, Y. Luo, X. Li, S. Xu
Chen C.Xia J., editor(s)
2004, Conference Paper, Progress in Environmental and Engineering Geophysics: Proceedings of the International Conference on Environmental and Engineering Geophysics, ICEEG 2004
This paper first explains the tau-p mapping method of extracting Rayleigh waves (LR waves) from field shot gathers. It also explains a mathematical model of physical character parameters of quality of high-grade roads. This paper then discusses an algorithm of computing dispersion curves using adjacent channels. Shear velocity and physical...
Information on habitat use of larval Ash Meadows speckled dace
R.R McShane, K.M. Swaim, G.G. Scoppettone
2004, Report
No abstract available ...
Earthquake triggering at Alaskan volcanoes following the 3 November 2002 Denali fault earthquake
S.C. Moran, J.A. Power, S.D. Stihler, J.J. Sanchez, J. Caplan-Auerbach
2004, Bulletin of the Seismological Society of America (94) S300-S309
The 3 November 2002 Mw 7.9 Denali fault earthquake provided an excellent opportunity to investigate triggered earthquakes at Alaskan volcanoes. The Alaska Volcano Observatory operates short-period seismic networks on 24 historically active volcanoes in Alaska, 247-2159 km distant from the mainshock epicenter. We searched for evidence of triggered seismicity by...
Three-dimensional fish tracking to evaluate the removable spillway weir at Lower Granite Dam during 2003, Annual report 2003
K.M Cash, T.W Hatton, E.C. Jones, R.J. Magie, N.S. Adams, D.W. Rondorf
2004, Report
Abstract not available ...
Water loss in the Potomac River basin during droughts
E.R. Hagen, J.E. Kiang, J.J.A. Dillow
Sehlke G.Hayes D.F.Stevens D.K., editor(s)
2004, Conference Paper, Proceedings of the 2004 World Water and Environmetal Resources Congress: Critical Transitions in Water and Environmetal Resources Management
The water loss phenomena in the Washington DC metropoliton area's (WMA) Potomac River water supply basin during droughts was analyzed. Gage errors, permitted withdrawals, evaporation, and transpiration by trees along the river were investigated to account for loss. The Interstate Commission on the Potomac River Basin (ICPRB) calculated potential gage...
