Classification methods for monitoring Arctic sea ice using OKEAN passive/active two-channel microwave data
Gennady I. Belchansky, David C. Douglas
2000, Remote Sensing of Environment (73) 307-322
This paper presents methods for classifying Arctic sea ice using both passive and active (2-channel) microwave imagery acquired by the Russian OKEAN 01 polar-orbiting satellite series. Methods and results are compared to sea ice classifications derived from nearly coincident Special Sensor Microwave Imager (SSM/I) and Advanced Very High Resolution Radiometer...
Methane and other hydrocarbon gases in sediment from the southeastern North American continental margin
K.A. Kvenvolden, T.D. Lorenson
2000, Conference Paper, Proceedings of the Ocean Drilling Program: Scientific Results
Residual concentrations and distributions of hydrocarbon gases from methane to n-heptane were measured in sediments at seven sites on Ocean Drilling Program (ODP) Leg 164. Three sites were drilled at the Cape Fear Diapir of the Carolina Rise, and one site was drilled on the Blake Ridge Diapir. Methane concentrations...
Migratory behavior and forebay delay of radio-tagged juvenile fall chinook salmon in a lower snake river impoundment
D.A. Venditti, D.W. Rondorf, J.M. Kraut
2000, North American Journal of Fisheries Management (20) 41-52
During July and August 1995-1997, we used radiotelemetry to estimate the migration rate of 405 juvenile fall chinook salmon Oncorhynchus tshawytscha (mean fork length, 138-144 mm) through Little Goose Reservoir. Migration rates decreased significantly as fish approached the dam. Median migration rates in 1995 were 26.0 km/d through the 45.9-km...
The effects of soil flooding on the establishment of cogongrass (Imperata cylindrica), a nonindigenous invader of the southeastern United States
S.E. King, J.B. Grace
2000, Wetlands (20) 300-306
Cogongrass (Imperata cylindrica), an invasive perennial introduced from Southeast Asia, is currently spreading throughout the southeastern United States from Florida to Louisiana. In the U.S., cogongrass is generally not considered a wetland species, although it’s range is expanding in regions with high wetland abundance. The objective of this...
Habitat and landscape correlates of presence, density, and species richness of birds wintering in forest fragments in Ohio
Paul F. Doherty Jr., Thomas C. Grubb Jr.
2000, The Wilson Bulletin (112) 388-394
We investigated the distribution of wintering woodland bird species in 47 very small, isolated, woodland fragments (0.54-6.01 ha) within an agricultural landscape in north-central Ohio. Our objectives were to determine correlations between temporal, habitat, and landscape variables and avian presence, density, and species richness within the smallest woodlots occupied by...
Evaluation of planar halogenated and polycyclic aromatic hydrocarbons in estuarine sediments using ethoxyresorufin-O-deethylase induction of H4IIE cells
R.W. Gale, E.R. Long, T.R. Schwartz, D. E. Tillitt
2000, Environmental Toxicology and Chemistry (19) 1348-1359
Polycyclic aromatic hydrocarbons (PAHs) and planar halogenated hydrocarbons (PHHs), including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) were determined in fractionated sediment extracts from the Hudson-Raritan estuary and Newark Bay, New Jersey, USA, as part of a comprehensive risk assessment. Contributions of PCDDs/PCDFs, PCBs, and PAHs to the total...
Method for flow cytometric monitoring of Renibacterium salmoninarum inactivation
R.J. Pascho, J.E. Ongerth
2000, Diseases of Aquatic Organisms (41) 181-193
The slow growth of Renibacterium salmoninarum limits the usefulness of culture as a research tool. Development of a 2-color flow cytometric assay to quantify the proportions of live and dead R. salmoninarum in a test population is described. Bacteria were simultaneously stained with fluorescein isothiocyanate-conjugated immunoglobulin and exposed to the...
Persistence of spilled oil on shores and its effects on biota
G.V. Irvine
Sheppard C.R.C., editor(s)
2000, Seas at the millennium - an environmental evaluation (3) 267-281
Over two million tonnes of oil are estimated to enter the world's oceans every year. A small percentage, but still a large volume, of this oil strands onshore, where its persistence is governed primarily by the action of physical forces. In some cases, biota influence the persistence of stranded oil...
Mercury(II) sorption to two Florida everglades peats
R.T. Drexel, G. R. Aiken, K. L. Nagy, J. N. Ryan
2000, Conference Paper, ACS Division of Environmental Chemistry, Preprints
[No abstract available]...
Biodegradation of disinfection byproducts as a potential removal process during aquifer storage recovery
J. E. Landmeyer, P. M. Bradley, J. M. Thomas
2000, Journal of the American Water Resources Association (36) 861-867
The biodegradation potential of two drinking water disinfection byproducts was investigated using aquifer materials obtained from approximately 100 and 200 meters below land surface in an aerobic aquifer system undergoing aquifer storage recovery of treated surface water. No significant biodegradation of a model trihalomethane compound, chloroform, was observed in aquifer...
Selective trace enrichment of chlorotriazine pesticides from natural waters and sediment samples using terbuthylazine molecularly imprinted polymers
I. Ferrer, F. Lanza, A. Tolokan, V. Horvath, B. Sellergren, G. Horvai, D. Barcelo
2000, Analytical Chemistry (72) 3934-3941
Two molecularly imprinted polymers were synthesized using either dichloromethane or toluene as the porogen and terbuthylazine as the template and were used as solid-phase extraction cartridges for the enrichment of six chlorotriazines (deisopropylatrazine, deethylatrazine, simazine, atrazine, propazine, and terbuthylazine) in natural water and sediment samples. The extracted samples were analyzed...
Integrating borehole logs and aquifer tests in aquifer characterization
Frederick L. Paillet, R.S. Reese
2000, Ground Water (38) 713-725
Integration of lithologic logs, geophysical logs, and hydraulic tests is critical in characterizing heterogeneous aquifers. Typically only a limited number of aquifer tests can be performed, and these need to be designed to provide hydraulic properties for the principle aquifers in the system. This study describes the integration of logs...
SHRIMP U-Pb geochronology of volcanic rocks, Belt Supergroup, western Montana: Evidence for rapid deposition of sedimentary strata
K. V. Evans, J. N. Aleinikoff, J. D. Obradovich, C.M. Fanning
2000, Canadian Journal of Earth Sciences (37) 1287-1300
New sensitive high resolution ion microprobe (SHRIMP) U–Pb zircon analyses from two tuffs and a felsic flow in the middle and upper Belt Supergroup of northwestern Montana significantly refine the age of sedimentation for this very thick (15-20 km) Middle Proterozoic stratigraphic sequence. In ascending stratigraphic order, the results are...
Late summer survival of adult female and juvenile spectacled eiders on the Yukon-Kuskokwim Delta, Alaska
Paul L. Flint, J. Barry, J.A. Morse, T.F. Fondell
2000, Waterbirds (23) 292-297
We used radio-telemetry to examine survival of adult female and juvenile Spectacled Eiders (Somateria fischeri) from 30 days after hatch until departure from the Yukon-Kuskokwim Delta (YKD) during 1997-1999. Juvenile survival was 71.4%; adult female survival was 88.5%. Mink (Mustella vison) were the most common predator identified for both adults...
A 22,000-year record of monsoonal precipitation from northern Chile's Atacama Desert
J.L. Betancourt, C. Latorre, J.A. Rech, Jay Quade, K.A. Rylander
2000, Science (289) 1542-1546
Fossil rodent middens and wetland deposits from the central Atacama Desert (22° to 24°S) indicate increasing summer precipitation, grass cover, and groundwater levels from 16.2 to 10.5 calendar kiloyears before present (ky B.P.). Higher elevation shrubs and summer-flowering grasses expanded downslope across what is now the edge of Absolute Desert,...
Origin of rainwater acidity near the Los Azufres geothermal field, Mexico
M.P. Verma, J.L. Quijano, Chad Johnson, J.Y. Gerardo, V. Arellano
2000, Geothermics (29) 593-608
The chemical and isotopic compositions of rainwater were monitored at Los Azufres geothermal field (88 MWe) and its surroundings during May - September 1995, which is the rainy season. Samples were collected from eight sites: three within the field, three in its surroundings and two sufficiently far from the field...
U.S. Geological Survey Assessment 2000: Estimates of undiscovered oil and gas resources for the world
Thomas S. Ahlbrandt, G. Whitney
2000, Minerals and Energy - Raw Materials Report (15) 36-39
Worldwide supply of oil and natural gas is ultimately linked to the geologic abundance and distribution of those fossil fuels. The U.S. Geological Survey (USGS) has completed a new assessment of the technically recoverable undiscovered oil and gas resources of the world. Nearly 1000 provinces were defined and known petroleum...
Development of a grid-cell topographic surface for Okefenokee Swamp, Georgia
Cynthia S. Loftin, Wiley Rasberry, Wiley M. Kitchens
2000, Wetlands (20) 487-499
The Okefenokee Swamp is a 160,000 ha freshwater wetland in Southeast Georgia, USA that developed in a landscape basin. Hydrologic variability across the swamp suggests that water-surface elevations are not uniform across the swamp. The topographic surface map discussed herein was developed to describe the swamp topography at local to...
Dating young groundwater with sulfur hexafluoride: Natural and anthropogenic sources of sulfur hexafluoride
Eurybiades Busenberg, Niel Plummer
2000, Water Resources Research (36) 3011-3030
Sulfur hexafluoride (SF6) is primarily of anthropogenic origin but also occurs naturally. The troposphere concentration of SF6 has increased from a steady state value of 0.054±0.009 to more than 4 parts per trillion volume during the past 40 years. An analytical procedure was developed for measuring concentrations of SF6 to less than...
The thermal inertia of Mars from the Mars Global Surveyor Thermal Emission Spectrometer
Bruce M. Jakosky, Michael T. Mellon, Hugh H. Kieffer, Phillip R. Christensen, E. Stacy Varnes, Steven W. Lee
2000, Journal of Geophysical Research E: Planets (105) 9643-9652
We have used Mars Global Surveyor (MGS) Thermal Emission Spectrometer thermal emission measurements to derive the thermal inertia of the Martian surface at the ∼100-km spatial scale. We have validated the use of nighttime-only measurements to derive thermal inertia as well as the use of a single wavelength band versus...
Redox conditions and the efficiency of chlorinated ethene biodegradation: Field studies
F. H. Chapelle, P. M. Bradley
2000, Conference Paper, ACS Division of Environmental Chemistry, Preprints
The effect of redox conditions on the efficiency of chlorinated ethene biodegradation was investigated at two field sites. One site (NAS Cecil Field, FL) is characterized by predominantly Fe(III)-reducing conditions in the contaminant source area, grading to predominantly sulfate- reducing conditions downgradient. This sequence of redox conditions led to relatively...
Soil organic matter characteristics in size fractions of water-stable aggregates and ultrasonically-dispersed particles
L.M. Choate, J. F. Ranville, K. A. Thorn, D.L. Macalady, A.L. Bunge
2000, Conference Paper, ACS Division of Environmental Chemistry, Preprints
[No abstract available]...
Cadmium toxicity among wildlife in the Colorado Rocky Mountains
J.R. Larison, G.E. Likens, J.W. Fitzpatrick, J.G. Crock
2000, Nature (406) 181-183
Cadmium is known to be both extremely toxic and ubiquitous in natural environments. It occurs in almost all soils, surface waters and plants, and it is readily mobilized by human activities such as mining. As a result, cadmium has been named as a potential health threat to wildlife species; however,...
Strain accumulation across the Eastern California Shear Zone at latitude 36°30'N
Weijun Gan, Jerry L. Svarc, J.C. Savage, W.H. Prescott
2000, Journal of Geophysical Research B: Solid Earth (105) 16229-16236
The motion of a linear array of monuments extending across the Eastern California Shear Zone (ECSZ) has been measured from 1994 to 1999 with the Global Positioning System. The linear array is oriented N54°E, perpendicular to the tangent to the local small circle drawn about the Pacific-North America pole of...
Sequential dome-collapse nuées ardentes analyzed from broadband seismic data, Merapi Volcano, Indonesia
A. Brodscholl, S.B. Kirbani, B. Voight
2000, Journal of Volcanology and Geothermal Research (100) 363-369
During the sequential dome collapse of Merapi Volcano on 22 November 1994, a broadband seismic station on the western slope was the only operational seismic equipment that provided continuous on-scale recording of the event. According to visual and seismic observations, the collapse activity lasted about 10 h. We divide the...
