The lizard fauna of Guam's fringing islets: Island biogeography, phylogenetic history, and conservation implications
G. Perry, G.H. Rodda, T. H. Fritts, T.R. Sharp
1998, Global Ecology and Biogeography Letters (7) 353-365
We sampled the lizard fauna of twenty-two small islets fringing the Pacific island of Guam and used these data to shed light on the processes responsible for present-day diversity. Habitat diversity, measured by islet area and vegetation complexity, was significantly correlated with the number of species found on an islet....
The role of olfaction in homing and estuarine migratory behavior of yellow-phase American eels
G.P. Barbin
1998, Canadian Journal of Fisheries and Aquatic Sciences (55) 564-575
The role of olfaction in homing migrations of American eels (Anguilla rostrata) was examined in the Penobscot Estuary, Maine, U.S.A. Ultrasonic telemetry was used to track continuously (65 ?? 12 h) 16 yellow eels displaced from a capture site. Four eels were not treated, eight rendered anosmic, and four rendered...
Comparison of hydrochemical tracers to estimate source contributions to peak flow in a small, forested, headwater catchment
Karen C. Rice, George M. Hornberger
1998, Water Resources Research (34) 1755-1766
Three-component (throughfall, soil water, groundwater) hydrograph separations at peak flow were performed on 10 storms over a 2-year period in a small forested catchment in north-central Maryland using an iterative and an exact solution. Seven pairs of tracers (deuterium and oxygen 18, deuterium and chloride, deuterium and sodium, deuterium and...
Small-scale morphology across the surf zone
E.B. Thornton, J.L. Swayne, J.R. Dingler
1998, Marine Geology (145) 173-196
Small-scale (< 5 m horizontal length) nearshore morphologic height variations were measured by combining CRAB surveys with bed elevations acquired with a 1 MHz sonic altimeter mounted on the CRAB during the October Phase of the DUCK94 experiment. Bedform plan views were recorded simultaneously using a 500 kHz side-scan sonar...
Geology of the Sierra de Fiambala, northwestern Argentina: Implications for Early Palaeozoic Andean tectonics
G.C. Grissom, S.M. DeBari, L.W. Snee
1998, Geological Society Special Publication (142) 297-323
Field mapping in conjunction with structural, metamorphic, and geochronological data document the tectono-thermal history of exhumed deep crustal rocks in the Sierra de Fiambalá, NW Argentina. The range consists of two structural blocks distinguished by different metasedimentary sequences and different grades of metamorphism. Orthogneiss and paragneiss in...
Abnormal organic-matter maturation in the Yinggehai Basin, South China Sea: Implications for hydrocarbon expulsion and fluid migration from overpressured systems
F. Hao, S. Li, W. Dong, Z. Hu, B. Huang
1998, Journal of Petroleum Geology (21) 427-444
Three superimposed pressure systems are present in the Yinggehai Basin, South China Sea. A number of commercial, thermogenic gas accumulations have been found in an area in which shale diapirs occur. Because the reservoir intervals are shallow and very young, they must have filled with gas rapidly. The thick (up...
Rapid toxicity assessment of sediments from estuarine ecosystems: A new tandem in vitro testing approach
B. Thomas Johnson, Edward R. Long
1998, Environmental Toxicology and Chemistry (17) 1099-1106
Microtox® and Mutatox® were used to evaluate the acute toxicity and genotoxicity, respectively, of organic sediment extracts from Pensacola Bay and St. Andrew Bay, two estuaries that cover about 273 and 127 km2, respectively, along the Gulf coast of Florida, USA. The sensitivity and selectivity of these two bioluminescent toxicity...
Effects of conifer release with glyphosate on summer forage abundance for deer in Maine
J.K. Vreeland, F. A. Servello, B. Griffith
1998, Canadian Journal of Forest Research (28) 1574-1578
Effects of conifer release with glyphosate on summer forage availability for large herbivores in northern forests have received relatively little study. We determined effects of glyphosate treatment of clearcuts on abundance of summer foods for white-tailed deer (Odocoileus virginianus) at 1 and 7-10 years posttreatment. We measured the abundance (percent...
Cotton herbicides in the surface waters of the Mississippi Alluvial Plain (the Delta)
R.H. Coupe, R.A. Rebich
1998, Conference Paper, International Water Resources Engineering Conference - Proceedings
The U.S. Geological Survey is conducting two studies to assess the environmental fate of herbicides used in cotton producing areas of the southeastern United States. The first study is evaluating surface-water quality on a regional basis and relating water quality to land use. The second study is examining the use...
Imperilled wetlands - Book review: Mangroves and saltmarshes
Thomas J. Smith III
1998, Nature (395) 131-132
Review info: Mangroves and saltmarshes. Edited by Eric Wolanski and Charles S. Hopkinson Jr., 1996....
Organochlorines, mercury, and selenium in great blue heron eggs from Indiana Dunes National Lakeshore, Indiana
Thomas W. Custer, Randy K. Hines, Paul M. Stewart, Mark J. Melancon, Diane S. Henshel, Daniel W. Spearks
1998, Journal of Great Lakes Research (24) 3-11
In 1993, 20 great blue heron (Ardea herodias; GBH) eggs (one per nest) were collected from a colony at the Indiana Dunes National Lakeshore, Indiana (INDU). The eggs were artificially incubated until pipping and were then analyzed for organochlorines, mercury, and selenium. Livers of embryos were analyzed for hepatic microsomal...
Tsivat Basin conduit system persists through two surges, Bering Piedmont Glacier, Alaska
P.J. Fleisher, D.H. Cadwell, E.H. Muller
1998, Geological Society of America Bulletin (110) 877-887
The 1993–1995 surge of Bering Glacier, Alaska, occurred in two distinct phases. Phase 1 of the surge began on the eastern sector in July, 1993 and ended in July, 1994 after a powerful outburst of subglacial meltwater into Tsivat Lake basin on the north side of Weeping Peat Island. Within...
Methodology and implications of maximum paleodischarge estimates for mountain channels, upper Animas River basin, Colorado, U.S.A.
J. Pruess, Ellen E. Wohl, Robert D. Jarrett
1998, Arctic and Alpine Research (30) 40-50
Historical and geologic records may be used to enhance magnitude estimates for extreme floods along mountain channels, as demonstrated in this study from the San Juan Mountains of Colorado. Historical photographs and local newspaper accounts from the October 1911 flood indicate the likely extent of flooding and damage. A checklist...
Metal concentrations in surface sediments of Boston Harbor: Changes with time
Michael H. Bothner, Marilyn R. Buchholtz ten Brink, F.T. Manheim
1998, Marine Environmental Research (45) 127-155
The concentrations of metals in surface sediments of Boston Harbor have decreased during the period 1977–1993. This conclusion is supported by analysis of: (1) surface sediments collected at monitoring stations in the outer harbor between 1977 and 1993; (2) metal concentration profiles in sediment cores from depositional areas of the...
Reproductive potential and fecundity of lake trout strains in southern and eastern waters of Lake Ontario, 1977-1994
Robert O’Gorman, Joseph H. Elrod, Clifford P. Schneider
1998, Journal of Great Lakes Research (24) 131-144
We assessed the reproductive potential of various genetic strains of hatchery lake trout (Salvelinus namaycush) in southern and eastern Lake Ontario from indices of fecundity and indices of male abundance. Indices were constructed from catches of mature lake trout in gill nets during September 1980 to 1994 after correcting for...
A comparison of zero-order, first-order, and monod biotransformation models
B.A. Bekins, E. Warren, E.M. Godsy
1998, Ground Water (36) 261-268
Under some conditions, a first-order kinetic model is a poor representation of biodegradation in contaminated aquifers. Although it is well known that the assumption of first-order kinetics is valid only when substrate concentration, S, is much less than the half-saturation constant, K(s), this assumption is often made without verification of...
Photoenhanced toxicity of a carbamate insecticide to early life stage anuran amphibians
A. Zaga, E. E. Little, C.F. Rabeni, Mark R. Ellersieck
1998, Environmental Toxicology and Chemistry (17) 2543-2553
Aican clawed frog (Xenopus laevis) and gray tree frog (Hyla versicolor) embryos and tadpoles were exposed to sublethal levels of carbaryl, a broad-spectrum insecticide, and ultraviolet radiation to determine interactive and sublethal effects. Ultraviolet intensity (UV-B [285–320 nm] plus UV-A [321–400 nm]) was controlled with various types of plastic filters...
Estimate of net trophic transfer efficiency of PCBs to Lake Michigan lake trout from their prey
Charles P. Madenjian, Robert J. Hesselberg, Timothy J. Desorcie, Larry J. Schmidt, Ralph M. Stedman, Richard T. Quintal, Linda J. Begnoche, Dora R. Passino-Reader
1998, Environmental Science & Technology (32) 886-891
Most of the polychlorinated biphenyl (PCB) body burden accumulated by lake trout (Salvelinus namaycush) from the Laurentian Great Lakes is from their food. We used diet information, PCB determinations in both lake trout and their prey, and bioenergetics modeling to estimate the efficiency with which Lake Michigan lake trout retain...
Europa: Initial Galileo Geological Observations
R. Greeley, R. Sullivan, J. Klemaszewski, K. Homan, J. W. Head III, R.T. Pappalardo, J. Veverka, B.E. Clark, T. V. Johnson, K.P. Klaasen, M. Belton, Jeff Moore, E. Asphaug, M. H. Carr, G. Neukum, T. Denk, C. R. Chapman, C.B. Pilcher, P.E. Geissler, R. Greenberg, R. Tufts
1998, Icarus (135) 4-24
Images of Europa from the Galileo spacecraft show a surface with a complex history involving tectonic deformation, impact cratering, and possible emplacement of ice-rich materials and perhaps liquids on the surface. Differences in impact crater distributions suggest that some areas have been resurfaced more recently than others; Europa could experience...
Observation of the seismic nucleation phase in the Ridgecrest, California, earthquake sequence
W.L. Ellsworth, G. C. Beroza
1998, Geophysical Research Letters (25) 401-404
Near-source observations of five M 3.8–5.2 earthquakes near Ridgecrest, California are consistent with the presence of a seismic nucleation phase. These earthquakes start abruptly, but then slow or stop before rapidly growing again toward their maximum rate of moment release. Deconvolution of instrument and path effects...
Effects of slip, slip rate, and shear heating on the friction of granite
M.L. Blanpied, T.E. Tullis, J.D. Weeks
1998, Journal of Geophysical Research B: Solid Earth (103) 489-511
The stability of fault slip is sensitive to the way in which frictional strength responds to changes in slip rate and in particular to the effective velocity dependence of steady state friction Δμss/Δ ln V. This quantity can vary substantially with displacement, temperature and slip rate. To investigate the physical basis...
Application of the top specified boundary layer (TSBL) approximation to initial characterization of an inland aquifer mineralization 1. Direct contact between fresh and saltwater
H. Rubin, R. W. Buddemeier
1998, Journal of Contaminant Hydrology (32) 353-376
This paper presents a basic study in generalized terms that originates from two needs: (1) to understand the major mechanisms involved in the mineralization of groundwater of the Great Bend Prairie aquifer of Kansas by saltwater originating from a deeper Permian bedrock formation, and (2) to develop simple, robust tools...
Photoprotective substance occurs primarily in outer layers of fish skin
D. L. Fabacher, E. E. Little
1998, Environmental Science and Pollution Research (5) 4-6
Methanol extracts of dorsal skin layers, eyes, gills, and livers from ultraviolet-B (UVB) radiation-sensitive and UVB-tolerant species of freshwater fish were examined for a substance that appears to be photoprotective. Significantly larger amounts of this substance were found in extracts of outer dorsal skin layers from both UVB-sensitive and UVB-tolerant...
Sulphur-radical control on petroleum formation rates
M. D. Lewan
1998, Nature (391) 164-166
Most petroleum is formed through the partial decomposition of kerogen (an insoluble sedimentary organic material) in response to thermal stress during subsurface burial in a sedimentary basin. Knowing the mechanisms and kinetics of this process allows the determination of the extent and timing of petroleum formation, which, in turn, are...
Seasonal migration and homing of channel catfish in the lower Wisconsin River, Wisconsin
Thomas D. Pellett, Gene J. Van Dyck, Jean V. Adams
1998, North American Journal of Fisheries Management (18) 85-95
A multiyear tag and recapture study was conducted to determine whether channel catfishIctalurus punctatus were migratory and if they had strong homing tendencies. Over 10,000 channel catfish were tagged from the lower Wisconsin River and adjacent waters of the upper Mississippi River during the 3-year sampling period. Data on movements were...
