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Page 2288, results 57176 - 57200

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Seasonal fish community variation in headwater mangrove creeks in the southwestern everglades: An examination of their role as dry-down refuges
Jennifer S. Rehage, W.F. Loftus
2007, Conference Paper, Bulletin of Marine Science
The connectivity between the fish community of estuarine mangroves and that of freshwater habitats upstream remains poorly understood. In the Florida Everglades, mangrove-lined creeks link freshwater marshes to estuarine habitats downstream and may act as dry-season refuges for freshwater fishes. We examined seasonal dynamics in the fish community of ecotonal...
Regional dynamics of grassland change in the western Great Plains
M.A. Drummond
2007, Conference Paper, Great Plains Research
This paper examines the contemporary land-cover changes in two western Great Plains ecoregions between 1973 and 2000. Agriculture and other land uses can have a substantial effect on grassland cover that varies regionally depending on the primary driving forces of change. In order to better understand change, the rates, types,...
Survival and breeding advantages of larger Black Brant (Branta bernicla nigricans) goslings: Within- and among-cohort variation
J.S. Sedinger, N.D. Chelgren
2007, The Auk (124) 1281-1293
We examined the relationship between mass late in the first summer and survival and return to the natal breeding colony for 12 cohorts (1986-1997) of female Black Brant (Branta bernicla nigricans). We used Cormack-Jolly-Seber methods and the program MARK to analyze capture-recapture data. Models included two kinds of residuals from...
Oceanography of Glacier Bay, Alaska: Implications for biological patterns in a glacial fjord estuary
L.L. Etherington, P.N. Hooge, Elizabeth Ross Hooge, D.F. Hill
2007, Estuaries and Coasts (30) 927-944
Alaska, U.S.A, is one of the few remaining locations in the world that has fjords that contain temperate idewater glaciers. Studying such estuarine systems provides vital information on how deglaciation affects oceanographic onditions of fjords and surrounding coastal waters. The oceanographic system of Glacier Bay, Alaska, is of particular interest...
ASAR images a diverse set of deformation patterns at Kilauea volcano, Hawai'i
Michael P. Poland
2007, Conference Paper
Since 2003, 27 independent look angles have been acquired by ENVISAT’s Advanced Synthetic Aperture Radar (ASAR) instrument over the island of Hawai`i, allowing for the formation of thousands of interferograms showing deformation of the ground surface. On Kīlauea volcano, a transition from minor to broad-scale summit inflation was observed by...
Crossing disciplines and scales to understand the critical zone
S.L. Brantley, M. B. Goldhaber, Ragnarsdottir K. Vala
2007, Elements (3) 307-314
The Critical Zone (CZ) is the system of coupled chemical, biological, physical, and geological processes operating together to support life at the Earth's surface. While our understanding of this zone has increased over the last hundred years, further advance requires scientists to cross disciplines and scales to integrate understanding of...
Forage nutritive quality in the Serengeti ecosystem: The roles of fire and herbivory
T.M. Anderson, M.E. Ritchie, E. Mayemba, S. Eby, J.B. Grace, S.J. McNaughton
2007, American Naturalist (170) 343-357
Fire and herbivory are important determinants of nutrient availability in savanna ecosystems. Fire and herbivory effects on the nutritive quality of savanna vegetation can occur directly, independent of changes in the plant community, or indirectly, via effects on the plant community. Indirect effects can be further subdivided into those occurring...
Smallmouth bass and largemouth bass predation on juvenile Chinook salmon and other salmonids in the Lake Washington basin
R.A. Tabor, B.A. Footen, K.L. Fresh, M.T. Celedonia, F. Mejia, D.L. Low, L. Park
2007, North American Journal of Fisheries Management (27) 1174-1188
We assessed the impact of predation by smallmouth bass Micropterus dolomieu and largemouth bass M. salmoides on juveniles of federally listed Chinook salmon Oncorhynchus tshawytscha and other anadromous salmonid populations in the Lake Washington system. Bass were collected with boat electrofishing equipment in the south end of Lake Washington (February-June)...
Voluminous low δ18O magmas in the late Miocene Heise volcanic field, Idaho: Implications for the fate of Yellowstone hotspot calderas
I.N. Bindeman, Kathryn E. Watts, A.K. Schmitt, Lisa Morgan, Pat Shanks
2007, Geology (35) 1019-1022
We report oxygen isotope compositions of phenocrysts and U-Pb ages of zircons in four large caldera-forming ignimbrites and post-caldera lavas of the Heise volcanic field, a nested caldera complex in the Snake River Plain, that preceded volcanism in Yellowstone. Early eruption of three normal δ18O voluminous ignimbrites with δ18Oquartz =...
High rates of energy expenditure and water flux in free-ranging Point Reyes mountain beavers Aplodontia rufa phaea
D.E. Crocker, N. Kofahl, G.D. Fellers, N.B. Gates, D.S. Houser
2007, Physiological and Biochemical Zoology (80) 635-642
We measured water flux and energy expenditure in free-ranging Point Reyes mountain beavers Aplodontia rufa phaea by using the doubly labeled water method. Previous laboratory investigations have suggested weak urinary concentrating ability, high rates of water flux, and low basal metabolic rates in this species. However, free-ranging measurements from hygric...
Nanotechnology - An emerging technology
D. Buckingham
2007, Mining Engineering (59) 23-29
The science of nanotechnology is still in its infancy. However, progress is being made in research and development of potential beneficial properties of nanomaterials that could play an integral part in the development of new and changing uses for mineral commodities. Nanotechnology is a kind of toolbox that allows industry...
Forest dynamics in Oregon landscapes: Evaluation and application of an individual-based model
R. T. Busing, A.M. Solomon, R.B. McKane, C.A. Burdick
2007, Ecological Applications (17) 1967-1981
The FORCLIM model of forest dynamics was tested against field survey data for its ability to simulate basal area and composition of old forests across broad climatic gradients in western Oregon, USA. The model was also tested for its ability to capture successional trends in ecoregions of the west Cascade...
Hydrothermal nontronite formation at Eolo Seamount (Aeolian volcanic arc, Tyrrhenian Sea)
V.M. Dekov, George D. Kamenov, Jens Stummeyer, M. Thiry, C. Savelli, Wayne C. Shanks, D. Fortin, E. Kuzmann, A. Vertes
2007, Chemical Geology (245) 103-119
A sediment core containing a yellowish-green clay bed was recovered from an area of extensive hydrothermal deposition at the SE slope of the Eolo Seamount, Tyrrhenian Sea. The clay bed is composed of pure nontronite (described for the first time in the Tyrrhenian Sea), which appears to be the most...
Recent results on the spatiotemporal modelling and comparative analysis of Black Death and bubonic plague epidemics
G. Christakos, Ricardo A. Olea, H.-L. Yu
2007, Public Health (121) 700-720
Background: This work demonstrates the importance of spatiotemporal stochastic modelling in constructing maps of major epidemics from fragmentary information, assessing population impacts, searching for possible etiologies, and performing comparative analysis of epidemics. Methods: Based on the theory previously published by the authors and incorporating new knowledge bases, informative maps of...
A new focus on groundwater-seawater interactions
C. Langevin, W. Sanford, M. Polemio, P. Povinec
2007, Conference Paper, IAHS-AISH Publication
In summary, the papers in this volume present research by those working from the marine and the terrestrial sides of issues related to SGD and groundwater-seawater interactions. The first part of this paper provides an introduction and background information on the subject of SGD and groundwater-seawater interactions. The second part...
Genotyping of Korean isolates of infectious hematopoietic necrosis virus (IHNV) based on the glycoprotein gene
W.-S. Kim, M.-J. Oh, T. Nishizawa, J. W. Park, Gael Kurath, M. Yoshimizu
2007, Archives of Virology (152) 2119-2124
Glycoprotein (G) gene nucleotide sequences of four Korean isolates of infectious hematopoietic necrosis virus (IHNV) were analyzed to evaluate their genetic relatedness to worldwide isolates. All Korean isolates were closely related to Japanese isolates of genogroup JRt rather than to those of North American and European genogroups. It is believed...
Aeromagnetic mapping of the structure of Pine Canyon caldera and Chisos Mountains intrusion, Big Bend National Park, Texas
B. J. Drenth, C. A. Finn
2007, Geological Society of America Bulletin (119) 1521-1534
Analysis of aeromagnetic and gravity data reveals new details of the structure, igneous geology, and temporal evolution of the prominent, enigmatic ca.32 Ma Pine Canyon caldera and the Chisos Mountains (Big Bend National Park, Texas). The main caldera-filling Pine Canyon Rhyolite, the oldest member of the South Rim Formation, is...
Observations of magnetite dissolution in poorly drained soils
D.A. Grimley, N.K. Arruda
2007, Soil Science (172) 968-982
Dissolution of strongly magnetic minerals is a common and relatively rapid phenomenon in poorly drained soils of the central United States, resulting in low magnetic susceptibility (MS). Low Eh reducing conditions are primarily responsible for magnetic mineral dissolution; a process likely mediated by iron-reducing bacteria in the presence of soil...
Investigation of magnesium isotope fractionation during basalt differentiation: Implications for a chondritic composition of the terrestrial mantle
F.-Z. Teng, M. Wadhwa, Rosalind T. Helz
2007, Earth and Planetary Science Letters (261) 84-92
To investigate whether magnesium isotopes are fractionated during basalt differentiation, we have performed high-precision Mg isotopic analyses by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) on a set of well-characterized samples from Kilauea Iki lava lake, Hawaii, USA. Samples from the Kilauea Iki...
Modeling the influence of river discharge on salt intrusion and residual circulation in Danshuei River estuary, Taiwan
W.-C. Liu, W.-B. Chen, R. T. Cheng, M.-H. Hsu, A.Y. Kuo
2007, Continental Shelf Research (27) 900-921
A 3-D, time-dependent, baroclinic, hydrodynamic and salinity model was implemented and applied to the Danshuei River estuarine system and the adjacent coastal sea in Taiwan. The model forcing functions consist of tidal elevations along the open boundaries and freshwater inflows from the main stream and major tributaries in the Danshuei...
Mammoth (Mammuthus sp.) excavation on a college campus in Western Illinois, USA
J.D. Treworgy, J.J. Saunders, D.A. Grimley
2007, Quaternary International (169-170) 24-28
The discovery of the remains of a mammoth, Mammuthus sp., on the Principia College campus in Elsah, Illinois, has allowed for careful excavation by students over several years. The mammoth is relatively well preserved in late Wisconsin Peoria Silt on the top of the bluffs of the Mississippi River. The...
Establishing a baseline and faunal history in amphibian monitoring programs: The amphibians of Harris Neck, GA
C.K. Dodd Jr., W.J. Barichivich
2007, Southeastern Naturalist (6) 125-134
We conducted an intensive inventory of Harris Neck National Wildlife Refuge in coastal Georgia to determine the feasibility of establishing an amphibian monitoring program at this location. Thirteen semi-aquatic amphibian species were identified at 21 locations. Amphibian species richness at Harris Neck was similar to that of nearby barrier islands....