Sources, bioavailability, and photoreactivity of dissolved organic carbon in the Sacramento-San Joaquin River Delta
R. Stepanauskas, M.A. Moran, B.A. Bergamaschi, J.T. Hollibaugh
2005, Biogeochemistry (74) 131-149
We analyzed bioavailability, photoreactivity, fluorescence, and isotopic composition of dissolved organic carbon (DOC) collected at 13 stations in the Sacramento-San Joaquin River Delta during various seasons to estimate the persistence of DOC from diverse shallow water habitat sources. Prospective large-scale wetland restorations in the Delta may change the amount of...
Total mercury concentrations in fillets of bluegill, redear sunfish, largemouth bass, and other fishes from Lake Natoma, Sacramento County, California
M. K. Saiki, B.A. Martin, T.W. May, Charles N. Alpers
2005, California Fish and Game (91) 193-206
This study was conducted during September-October 2002 to verify preliminary findings of elevated total mercury concentrations in skinless fillets of sportfishes inhabiting Lake Natoma. Although we measured total mercury concentrations, most mercury in fish flesh occurs in the methylated form. In August 2000, other investigators collected a small number of...
Evidence for a global seismic-moment release sequence
C. G. Bufe, D. M. Perkins
2005, Bulletin of the Seismological Society of America (95) 833-843
Temporal clustering of the larger earthquakes (foreshock-mainshock-aftershock) followed by relative quiescence (stress shadow) are characteristic of seismic cycles along plate boundaries. A global seismic-moment release history, based on a little more than 100 years of instrumental earthquake data in an extended version of the catalog of Pacheco and Sykes (1992),...
Movements of walruses radio-tagged in Bristol Bay, Alaska
Chadwick V. Jay, Susan Hills
2005, Arctic (58) 192-202
Satellite radio-location data from 57 adult male Pacific walruses (Odobenus rosmarus divergens) were used to estimate haul-out fidelity, broadly describe seasonal foraging distributions, and determine the approximate timing of autumn migration from Bristol Bay, Alaska. Data were collected intermittently during 1987–91 and 1995–2000, primarily during the period from May to...
Reduced growth and survival of larval razorback sucker fed selenium-laden zooplankton
Steven J. Hamilton, Kevin J. Buhl, Fern A. Bullard, Susan McDonald
2005, Ecotoxicology and Environmental Safety (61) 190-208
Four groups of larval razorback sucker, an endangered fish, were exposed to selenium-laden zooplankton and survival, growth, and whole-body residues were measured. Studies were conducted with 5, 10, 24, and 28-day-old larvae fed zooplankton collected from six sites adjacent to the Green River, Utah. Water where zooplankton were collected had...
Eastern rim of the Chesapeake Bay impact crater: Morphology, stratigraphy, and structure
C. W. Poag
2005, Special Paper of the Geological Society of America 117-130
This study reexamines seven reprocessed (increased vertical exaggeration) seismic reflection profiles that cross the eastern rim of the Chesapeake Bay impact crater. The eastern rim is expressed as an arcuate ridge that borders the crater in a fashion typical of the "raised" rim documented in many well preserved complex impact...
Reconnaissance study of late quaternary faulting along Cerro Goden fault zone, western Puerto Rico
P. Mann, C.S. Prentice, J.-C. Hippolyte, N.R. Grindlay, L.J. Abrams, D. Lao-Davila
2005, Special Paper of the Geological Society of America (385) 115-137
The Cerro Goden fault zone is associated with a curvilinear, continuous, and prominent topographic lineament in western Puerto Rico. The fault varies in strike from northwest to west. In its westernmost section, the fault is ∼500 m south of an abrupt, curvilinear mountain front separating the 270- to 361-m-high La...
Forest cover influences dispersal distance of white-tailed deer
E.S. Long, Duane R. Diefenbach, C.S. Rosenberry, B.D. Wallingford, M.D. Grund
2005, Journal of Mammalogy (86) 623-629
Animal dispersal patterns influence gene flow, disease spread, population dynamics, spread of invasive species, and establishment of rare or endangered species. Although differences in dispersal distances among taxa have been reported, few studies have described plasticity of dispersal distance among populations of a single species. In 2002-2003, we radiomarked 308...
Subduction-zone magnetic anomalies and implications for hydrated forearc mantle
R.J. Blakely, T.M. Brocher, R.E. Wells
2005, Geology (33) 445-448
Continental mantle in subduction zones is hydrated by release of water from the underlying oceanic plate. Magnetite is a significant byproduct of mantle hydration, and forearc mantle, cooled by subduction, should contribute to long-wavelength magnetic anomalies above subduction zones. We test this hypothesis with a quantitative model of the Cascadia...
Progression of methanogenic degradation of crude oil in the subsurface
B.A. Bekins, F. D. Hostettler, W.N. Herkelrath, G. N. Delin, E. Warren, H.I. Essaid
2005, Environmental Geosciences (12) 139-152
Our results show that subsurface crude-oil degradation rates at a long-term research site were strongly influenced by small-scale variations in hydrologic conditions. The site is a shallow glacial outwash aquifer located near Bemidji in northern Minnesota that became contaminated when oil spilled from a broken pipeline in August 1979....
Stratigraphic and geochemical evolution of an oceanic arc upper crustal section: The Jurassic Talkeetna Volcanic Formation, south-central Alaska
P.D. Clift, A.E. Draut, P.B. Kelemen, J. Blusztajn, A. Greene
2005, Geological Society of America Bulletin (117) 902-925
The Early Jurassic Talkeetna Volcanic Formation forms the upper stratigraphic level of an oceanic volcanic arc complex within the Peninsular Terrane of south-central Alaska. The section comprises a series of lavas, tuffs, and volcaniclastic debris-How and flow turbidite deposits, showing significant lateral facies variability. There is a general trend toward...
Distinguishing base-level change and climate signals in a Cretaceous alluvial sequence
T. White, B. Witzke, G.A. Ludvigson, R. Brenner
2005, Geology (33) 13-16
We present the results of oxygen isotope and electron-microprobe analyses of sphaerosiderites obtained from Cretaceous paleosols in Iowa. The sphaerosiderite ??18O values record Cretaceous meteoric groundwater chemistry and an overall waning of brackish groundwater inundation during alluvial-plain aggradation and soil genesis. We focus on horizons that precipitated from freshwater, in...
Radium isotopes in Cayuga Lake, New York: Indicators of inflow and mixing processes
T. F. Kraemer
2005, Limnology and Oceanography (50) 158-168
Naturally occurring radium isotopes (223Ra, 224Ra, 226Ra, and 228Ra) were measured in lake and tributary water of Cayuga Lake, New York, during the course of a vernal inflow event in the spring of 2001. A large influx of groundwater, probably from a carbonate aquifer, entered the lake at its extreme...
Telemedicine diffusion in a developing country: The case of India (March 2004)
A. Pal, V.W.A. Mbarika, F. Cobb-Payton, P. Datta, S. McCoy
2005, IEEE Transactions on Information Technology in Biomedicine (9) 59-65
Telemedicine (health-care delivery where physicians examine distant patients using telecommunications technologies) has been heralded as one of several possible solutions to some of the medical dilemmas that face many developing countries. In this study, we examine the current state of telemedicine in a developing country, India. Telemedicine has brought a...
Landscape characteristics of Rhizophora mangle forests and propagule deposition in coastal environments of Florida (USA)
R. Sengupta, B. Middleton, C. Yan, M. Zuro, H. Hartman
2005, Landscape Ecology (20) 63-72
Field dispersal studies are seldom conducted at regional scales even though reliable information on mid-range dispersal distance is essential for models of colonization. The purpose of this study was to examine the potential distance of dispersal of Rhizophora mangle propagules by comparing deposition density with landscape characteristics of mangrove forests....
Parallel Fortran-MPI software for numerical inversion of the Laplace transform and its application to oscillatory water levels in groundwater environments
X. Zhan
2005, Environmental Modelling and Software (20) 279-284
A parallel Fortran-MPI (Message Passing Interface) software for numerical inversion of the Laplace transform based on a Fourier series method is developed to meet the need of solving intensive computational problems involving oscillatory water level's response to hydraulic tests in a groundwater environment. The software is a parallel version of...
Landscape resistance to frog movements
M. J. Mazerolle, A. Desrochers
2005, Canadian Journal of Zoology (83) 455-464
An animal's capacity to recolonize a patch depends on at least two components: its ability to detect the patch and its ability to reach it. However, the disruption of such processes by anthropic disturbances could explain low animal abundance patterns observed by many investigators in certain landscapes. Through field experiments,...
The calcite → aragonite transformation in low-Mg marble: Equilibrium relations, transformations mechanisms, and rates
Bradley R. Hacker, David C. Rubie, Stephen H. Kirby, Steven R. Bohlen
2005, Journal of Geophysical Research B: Solid Earth (110) 1-16
Experimental transformation of a rather pure natural calcite marble to aragonite marble did not proceed via the expected straightforward polymorphic replacement. Instead, the small amount of Mg in the starting material (0.36 wt %) was excluded from the growing aragonite and diffused preferentially into the remaining calcite grains, producing Mg-rich...
Crack azimuths on Europa: The G1 lineament sequence revisited
A.R. Sarid, R. Greenberg, G.V. Hoppa, D.M. Brown Jr., P. Geissler
2005, Icarus (173) 469-479
The tectonic sequence in the anti-jovian area covered by regional mapping images from Galileo's orbit E15 is determined from a study of cross-cutting relationships among lineament features. The sequence is used to test earlier results from orbit G1, based on lower resolution images, which appeared to display a progressive change...
Hierarchical faunal filters: An approach to assessing effects of habitat and nonnative species on native fishes
M.C. Quist, F.J. Rahel, W.A. Hubert
2005, Ecology of Freshwater Fish (14) 24-39
Understanding factors related to the occurrence of species across multiple spatial and temporal scales is critical to the conservation and management of native fishes, especially for those species at the edge of their natural distribution. We used the concept of hierarchical faunal filters to provide a framework for investigating the...
Surface deformation associated with the March 1996 earthquake swarm at Akutan Island, Alaska, revealed by C-band ERS and L-band JERS radar interferometry
Z. Lu, C. Wicks Jr., O. Kwoun, J.A. Power, D. Dzurisin
2005, Canadian Journal of Remote Sensing (31) 7-20
In March 1996, an intense earthquake swarm beneath Akutan Island, Alaska, was accompanied by extensive ground cracking but no eruption of Akutan volcano. Radar interferograms produced from L-band JERS-1 and C-band ERS-1/2 images show uplift associated with the swarm by as much as 60 cm on the western...
Distribution of aseismic slip rate on the Hayward fault inferred from seismic and geodetic data
D.A. Schmidt, R. Burgmann, R.M. Nadeau, M. d'Alessio
2005, Journal of Geophysical Research B: Solid Earth (110) 1-15
We solve for the slip rate distribution on the Hayward fault by performing a least squares inversion,of geodetic and seismic data sets. Our analysis focuses on the northern 60 km of the fault. Interferometric synthetic aperture radar (InSAR) data from 13 independent ERS interferograms are stacked to obtain range change...
Population genetic structure of annual and perennial populations of Zostera marina L. along the Pacific coast of Baja California and the Gulf of California
Raquel Muñiz-Salazar, Sandra L. Talbot, George K. Sage, David H. Ward, Alejandro Cabello-Pasini
2005, Molecular Ecology (14) 711-722
The Baja California peninsula represents a biogeographical boundary contributing to regional differentiation among populations of marine animals. We investigated the genetic characteristics of perennial and annual populations of the marine angiosperm, Zostera marina, along the Pacific coast of Baja California and in the Gulf of California, respectively. Populations of Z....
The persistence of the water budget myth and its relationship to sustainability
J.F. Devlin, M. Sophocleous
2005, Hydrogeology Journal (13) 549-554
Sustainability and sustainable pumping are two different concepts that are often used interchangeably. The latter term refers to a pumping rate that can be maintained indefinitely without mining an aquifer, whereas the former term is broader and concerns such issues as ecology and water quality, among others, in addition to...
Geographic variation in survival and migratory tendency among North American Common Mergansers
John M. Pearce, John A. Reed, Paul L. Flint
2005, Journal of Field Ornithology (76) 109-118
Movement ecology and demographic parameters for the Common Merganser (Mergus merganser americanus) in North America are poorly known. We used band-recovery data from five locations across North America spanning the years 1938–1998 to examine migratory patterns and estimate survival rates. We examined competing time-invariant, age-graduated models with program MARK...
