Evidence for fish dispersal from spatial analysis of stream network topology
N.P. Hitt, P. L. Angermeier
2008, Journal of the North American Benthological Society (27) 304-320
Developing spatially explicit conservation strategies for stream fishes requires an understanding of the spatial structure of dispersal within stream networks. We explored spatial patterns of stream fish dispersal by evaluating how the size and proximity of connected streams (i.e., stream network topology) explained variation in fish assemblage structure and how...
United states national land cover data base development 1992-2001 and beyond
L. Yang
2008, Conference Paper, 2008 International Workshop on Earth Observation and Remote Sensing Applications, EORSA
An accurate, up-to-date and spatially-explicate national land cover database is required for monitoring the status and trends of the nation's terrestrial ecosystem, and for managing and conserving land resources at the national scale. With all the challenges and resources required to develop such a database, an innovative and scientifically sound...
Seasonal survival of radiomarked emperor geese in western Alaska
Jerry W. Hupp, Joel A. Schmutz, Craig R. Ely
2008, Journal of Wildlife Management (72) 1584-1595
The population of emperor geese (Chen canagica) in western Alaska, USA, declined by >50% from the 1960s to the mid‐1980s and has increased only slightly since. Rates of population increase among arctic geese are especially sensitive to changes in adult survival. Improving adult survival in seasons or geographic areas where...
Are fractal dimensions of the spatial distribution of mineral deposits meaningful?
G. L. Raines
2008, Natural Resources Research (17) 87-97
It has been proposed that the spatial distribution of mineral deposits is bifractal. An implication of this property is that the number of deposits in a permissive area is a function of the shape of the area. This is because the fractal density functions of deposits are dependent on the...
Laboratory and field evaluation of a flushable oxic limestone drain for treatment of net-acidic drainage from a flooded anthracite mine, Pennsylvania, USA
C.A. Cravotta III
2008, Applied Geochemistry (23) 3404-3422
This paper demonstrates the use of dissolution-rate data obtained in the laboratory to indicate the potential quality of effluent from a field-scale oxic limestone drain (OLD) treatment system for neutralization of dilute acidic mine drainage (AMD). Effluent from the Reevesdale Mine South Dip Tunnel, a large source of AMD and...
Patterns of volcanotectonic seismicity and stress during the ongoing eruption of the Soufrière Hills Volcano, Montserrat (1995-2007)
D.C. Roman, S. De Angelis, J.L. Latchman, Rickie White
2008, Journal of Volcanology and Geothermal Research (173) 230-244
The ongoing eruption of the Soufrière Hills Volcano, Montserrat, has been accompanied throughout by varying levels of high-frequency, ‘volcanotectonic’ (VT), seismicity. These earthquakes reflect the brittle response of the host rock to stresses generated within the magmatic system and thus reveal interesting and useful information about the structure of the...
Hepatic minerals of white-tailed and mule deer in the southern Black Hills, South Dakota
T.J. Zimmerman, J.A. Jenks, David M. Leslie Jr., R.D. Neiger
2008, Journal of Wildlife Diseases (44) 341-350
Because there is a paucity of information on the mineral requirements of free-ranging deer, data are needed from clinically healthy deer to provide a basis for the diagnosis of mineral deficiencies. To our knowledge, no reports are available on baseline hepatic mineral concentrations from sympatric white-tailed deer (Odocoileus virginianus) and...
Monitoring volcanic threats using ASTER satellite data
K. A. Duda, R. Wessels, M. Ramsey, J. Dehn
2008, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
This document summarizes ongoing activities associated with a research project funded by the national aeronautics and space administration (NASA) focusing on volcanic change detection through the use of satellite imagery. This work includes systems development as well as improvements in data analysis methods. Participating organizations include the NASA land processes...
Importance of physical and hydraulic characteristics to unionid mussels: A retrospective analysis in a reach of large river
S. J. Zigler, T.J. Newton, J. J. Steuer, M.R. Bartsch, J.S. Sauer
2008, Hydrobiologia (598) 343-360
Interest in understanding physical and hydraulic factors that might drive distribution and abundance of freshwater mussels has been increasing due to their decline throughout North America. We assessed whether the spatial distribution of unionid mussels could be predicted from physical and hydraulic variables in a reach of the Upper Mississippi...
Constraints on the Pleistocene chronology of sediments from the Lomonosov Ridge
M. O’Regan, J. King, J. Backman, M. Jakobsson, H. Palike, K. Moran, C. Heil, T. Sakamoto, T. M. Cronin, R.W. Jordan
2008, Paleoceanography (23)
Despite its importance in the global climate system, age-calibrated marine geologic records reflecting the evolultion of glacial cycles through the Pleistocene are largely absent from the central Arctic Ocean. This is especially true for sediments older than 200 ka. Three sites cored during the Integrated Ocean Drilling Program's Expedition 302,...
The influence of alewife year-class strength on prey selection and abundance of age-1 Chinook salmon in Lake Michigan
D.M. Warner, C.S. Kiley, R.M. Claramunt, D.F. Clapp
2008, Transactions of the American Fisheries Society (137) 1683-1700
We used growth and diet data from a fishery-independent survey of Chinook salmon Oncorhynchus tshawytscha, acoustic estimates of prey density and biomass, and statistical catch-at-age modeling to study the influence of the year-class strength of alewife Alosa pseudoharengus on the prey selection and abundance of age-1 Chinook salmon in Lake...
Representing general theoretical concepts in structural equation models: The role of composite variables
J.B. Grace, K.A. Bollen
2008, Environmental and Ecological Statistics (15) 191-213
Structural equation modeling (SEM) holds the promise of providing natural scientists the capacity to evaluate complex multivariate hypotheses about ecological systems. Building on its predecessors, path analysis and factor analysis, SEM allows for the incorporation of both observed and unobserved (latent) variables into theoretically-based probabilistic models. In this paper we...
Western juniper and ponderosa pine ecotonal climate-growth relationships across landscape gradients in southern Oregon
K.C. Knutson, D.A. Pyke
2008, Canadian Journal of Forest Research (38) 3021-3032
Forecasts of climate change for the Pacific northwestern United States predict warmer temperatures, increased winter precipitation, and drier summers. Prediction of forest growth responses to these climate fluctuations requires identification of climatic variables limiting tree growth, particularly at limits of free species distributions. We addressed this problem at the pine-woodland...
A consistent framework for Horton regression statistics that leads to a modified Hack's law
P.R. Furey, B.M. Troutman
2008, Geomorphology (102) 603-614
A statistical framework is introduced that resolves important problems with the interpretation and use of traditional Horton regression statistics. The framework is based on a univariate regression model that leads to an alternative expression for Horton ratio, connects Horton regression statistics to distributional simple scaling, and improves the accuracy in...
Demography and ecology of mangrove diamondback terrapins in a wilderness area of Everglades National Park, Florida, USA
K.M. Hart, C.C. McIvor
2008, Copeia 200-208
Diamondback Terrapins (Malaclemys terrapin) are distributed in brackish water habitats along the U.S. east coast from Massachusetts to Texas, but many populations may be in decline. Whereas ample morphological, behavioral, and reproductive information has been collected for terrapins living in temperate salt marsh habitats, comparatively little is known about mangrove...
Differences in evaporation between a floating pan and class a pan on land
J.R. Masoner, D.I. Stannard, S. C. Christenson
2008, Journal of the American Water Resources Association (44) 552-561
Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the...
Historical and current environmental influences on an endemic great plains fish
John R. Fischer, C.P. Paukert
2008, American Midland Naturalist (159) 364-377
Native fishes of the Great Plains are at risk of decline due to disturbances to physical habitat caused by changes in land and water use, as well as shifts in species assemblages driven by the invasion of introduced species with the loss of natives. We used historical and current fish...
Northerly surface winds over the eastern North Pacific Ocean in spring and summer
S.V. Taylor, D.R. Cayan, N.E. Graham, K.P. Georgakakos
2008, Journal of Geophysical Research D: Atmospheres (113)
Persistent spring and summer northerly surface winds are the defining climatological feature of the western coast of North America, especially south of the Oregon coast. Northerly surface winds are important for upwelling and a vast array of other biological, oceanic, and atmospheric processes. Intermittence in northerly coastal surface wind is...
Identification of spectral units on Phoebe
A. Coradini, F. Tosi, A.I. Gavrishin, F. Capaccioni, P. Cerroni, G. Filacchione, A. Adriani, R. H. Brown, G. Bellucci, V. Formisano, E. D’Aversa, J. I. Lunine, K. H. Baines, J.-P. Bibring, B. J. Buratti, R. N. Clark, D. P. Cruikshank, M. Combes, P. Drossart, R. Jaumann, Y. Langevin, D. L. Matson, T. B. McCord, V. Mennella, R.M. Nelson, P. D. Nicholson, B. Sicardy, Christophe Sotin, M.M. Hedman, G. B. Hansen, C. A. Hibbitts, M. Showalter, C. Griffith, G. Strazzulla
2008, Icarus (193) 233-251
We apply a multivariate statistical method to the Phoebe spectra collected by the VIMS experiment onboard the Cassini spacecraft during the flyby of June 2004. The G-mode clustering method, which permits identification of the most important features in a spectrum, is used on a small subset of data, characterized by...
Carbon dioxide of Pu`u`O`o volcanic plume at Kilauea retrieved by AVIRIS hyperspectral data
C. Spinetti, V. Carrere, M. Fabrizia Buongiorno, A. J. Sutton, T. Elias
2008, Remote Sensing of Environment (112) 3192-3199
A remote sensing approach permits for the first time the derivation of a map of the carbon dioxide concentration in a volcanic plume. The airborne imaging remote sensing overcomes the typical difficulties associated with the ground measurements and permits rapid and large views of the volcanic processes together with the measurements of volatile components exolving...
Multiyear riparian evapotranspiration and groundwater use for a semiarid watershed
R.L. Scott, W.L. Cable, T. E. Huxman, P.L. Nagler, M. Hernandez, D.C. Goodrich
2008, Journal of Arid Environments (72) 1232-1246
Riparian evapotranspiration (ET) is a major component of the surface and subsurface water balance for many semiarid watersheds. Measurement or model-based estimates of ET are often made on a local scale, but spatially distributed estimates are needed to determine ET over catchments. In this paper, we document the ET that...
Increased terrestrial to ocean sediment and carbon fluxes in the northern Chesapeake Bay associated with twentieth century land alteration
C. Saenger, T. M. Cronin, D. Willard, J. Halka, R. Kerhin
2008, Estuaries and Coasts (31) 492-500
We calculated Chesapeake Bay (CB) sediment and carbon fluxes before and after major anthropogenic land clearance using robust monitoring, modeling and sedimentary data. Four distinct fluxes in the estuarine system were considered including (1) the flux of eroded material from the watershed to streams, (2) the flux of suspended sediment...
Radar imaging of winter seismic survey activity in the National Petroleum Reserve-Alaska
Benjamin M. Jones, Russ Rykhus, Z. Lu, C.D. Arp, D.J. Selkowitz
2008, Polar Record (44) 227-231
During the spring of 2006, Radarsat-1 synthetic aperture radar (SAR) imagery was acquired on a continual basis for the Teshekpuk Lake Special Area (TLSA), in the northeast portion of the National Petroleum Reserve, Alaska (NPR-A) in order to monitor lake ice melting processes. During data processing, it was discovered that...
Mercury concentrations in blood and feathers of prebreeding Forster's terns in relation to space use of San Francisco Bay, California, USA, habitats
Joshua T. Ackerman, Collin A. Eagles-Smith, John Y. Takekawa, J.D. Bluso, T.L. Adelsbach
2008, Environmental Toxicology and Chemistry (27) 897-908
We examined mercury concentrations and space use of prebreeding Forster's terns (Sterna forsteri) in San Francisco Bay, California, USA, to assess factors influencing mercury levels in piscivorous birds. In 2005 and 2006, we collected blood and feathers from 122 Forster's terns and radio-marked and tracked 72 terns to determine locations...
Prioritizing conservation effort through the use of biological soil crusts as ecosystem function indicators in an arid region
M. A. Bowker, M. E. Miller, J. Belnap, T.D. Sisk, N.C. Johnson
2008, Conservation Biology (22) 1533-1543
Conservation prioritization usually focuses on conservation of rare species or biodiversity, rather than ecological processes. This is partially due to a lack of informative indicators of ecosystem function. Biological soil crusts (BSCs) trap and retain soil and water resources in arid ecosystems and function as major carbon and nitrogen fixers;...
