Comparison of the dust distributions in the innermost comae of comets-1P/Halley and 19P/Borrelly spacecraft observations
T.-M. Ho, N. Thomas, D. C. Boice, M. Combi, L.A. Soderblom, V. Tenishev
2007, Planetary and Space Science (55) 974-985
We present a comparative study of the inner comae of comets 1P/Halley and 19P/Borrelly using data from the Halley Multicolour Camera (HMC) onboard Giotto and the Miniature Integrated Camera and Spectrometer onboard Deep Space 1 (DS1). We show that the dust brightness dependence as a function of radial distance is...
Latin hypercube approach to estimate uncertainty in ground water vulnerability
J.J. Gurdak, J.E. McCray, G. Thyne, S.L. Qi
2007, Ground Water (45) 348-361
A methodology is proposed to quantify prediction uncertainty associated with ground water vulnerability models that were developed through an approach that coupled multivariate logistic regression with a geographic information system (GIS). This method uses Latin hypercube sampling (LHS) to illustrate the propagation of input error and estimate uncertainty associated with...
Correcting acoustic Doppler current profiler discharge measurement bias from moving-bed conditions without global positioning during the 2004 Glen Canyon Dam controlled flood on the Colorado River
J. W. Gartner, N. K. Ganju
2007, Limnology and Oceanography: Methods (5) 156-162
Discharge measurements were made by acoustic Doppler current profiler at two locations on the Colorado River during the 2004 controlled flood from Glen Canyon Dam, Arizona. Measurement hardware and software have constantly improved from the 1980s such that discharge measurements by acoustic profiling instruments are now routinely made over a...
Human influence on California fire regimes
A.D. Syphard, V. C. Radeloff, Jon E. Keeley, T. J. Hawbaker, M.K. Clayton, S. I. Stewart, R. B. Hammer
2007, Ecological Applications (17) 1388-1402
Periodic wildfire maintains the integrity and species composition of many ecosystems, including the mediterranean-climate shrublands of California. However, human activities alter natural fire regimes, which can lead to cascading ecological effects. Increased human ignitions at the wildland-urban interface (WUI) have recently gained attention, but fire activity and risk are typically...
PVTx properties of the CO2-H2O and CO2-H2O-NaCl systems below 647 K: assessment of experimental data and thermodynamic models
Jiawen Hu, Zhenhao Duan, Chen Zhu, I.-M. Chou
2007, Chemical Geology (238) 249-267
Evaluation of CO2 sequestration in formation brine or in seawater needs highly accurate experimental data or models of pressure–volume–temperature-composition (PVTx) properties for the CO2–H2O and CO2–H2O–NaCl systems. This paper presents a comprehensive review of the experimental PVTx properties and the thermodynamic models of these two systems. The following conclusions are drawn from the...
Isotopic characterization of three groundwater recharge sources and inferences for selected aquifers in the upper Klamath Basin of Oregon and California, USA
P.C. Palmer, M. W. Gannett, S.R. Hinkle
2007, Journal of Hydrology (336) 17-29
Stable isotope (??D and ??18O) signatures of three principal groundwater recharge areas in the 21,000-km2 upper Klamath Basin are used to infer recharge sources for aquifers in the interior parts of the basin. Two of the principal recharge areas, the Cascade Range on the western and southern margin of the...
Recent climate trends and implications for water resources in the Catskill Mountain region, New York, USA
Douglas A. Burns, Julian Klaus, Michael R. McHale
2007, Journal of Hydrology (336) 155-170
Climate scientists have concluded that the earth’s surface air temperature warmed by 0.6 °C during the 20th century, and that warming induced by increasing concentrations of greenhouse gases is likely to continue in the 21st century, accompanied by changes in the hydrologic cycle. Climate change has important implications in the Catskill...
Return to the wild: Translocation as a tool in conservation of the desert tortoise (Gopherus agassizii)
K.J. Field, C.R. Tracy, P.A. Medica, R.W. Marlow, P.S. Corn
2007, Biological Conservation (136) 232-245
Translocation could be used as a tool in conservation of the threatened Mojave Desert Tortoise (Gopherus agassizii) by moving individuals from harm's way and into areas where they could contribute to conservation of the species. Numerous factors may affect the success of translocations, including the conditions experienced by tortoises in...
Biological uptake of polychlorinated biphenyls by Macoma balthica from sediment amended with activated carbon
Pamela B. McLeod, Martine J. van den Heuvel-Greve, S. N. Luoma, R.G. Luthy
2007, Environmental Toxicology and Chemistry (26) 980-987
This work characterizes the efficacy of activated carbon amendment in reducing polychlorinated biphenyl (PCB) bioavailability to clams (Macoma balthica) from field-contaminated sediment (Hunters Point Naval Shipyard, San Francisco Bay, CA, USA). Test methods were developed for the use of clams to investigate the effects of...
Comparison of four approaches to a rock facies classification problem
M.K. Dubois, Geoffrey C. Bohling, S. Chakrabarti
2007, Computers & Geosciences (33) 599-617
In this study, seven classifiers based on four different approaches were tested in a rock facies classification problem: classical parametric methods using Bayes' rule, and non-parametric methods using fuzzy logic, k-nearest neighbor, and feed forward-back propagating artificial neural network. Determining the most effective classifier for geologic facies prediction in wells...
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....
A classification of U.S. estuaries based on physical and hydrologic attributes
V.D. Engle, J.C. Kurtz, L.M. Smith, C. Chancy, P. Bourgeois
2007, Environmental Monitoring and Assessment (129) 397-412
A classification of U.S. estuaries is presented based on estuarine characteristics that have been identified as important for quantifying stressor-response relationships in coastal systems. Estuaries within a class have similar physical and hydrologic characteristics and would be expected to demonstrate similar biological responses to stressor loads from the adjacent watersheds....
Quantifying foodweb interactions with simultaneous linear equations: Stable isotope models of the Truckee River, USA
L. Saito, C. Redd, S. Chandra, L. Atwell, C.H. Fritsen, Michael R. Rosen
2007, Journal of the North American Benthological Society (26) 642-662
Aquatic foodweb models for 2 seasons (relatively high- [March] and low-flow [August] conditions) were constructed for 4 reaches on the Truckee River using ??13C and ??15N data from periphyton, macroinvertebrate, and fish samples collected in 2003 and 2004. The models were constructed with isotope values that included measured periphyton signatures...
A genetic assessment of the recovery units for the mojave population of the desert tortoise, Gopherus agassizii
R. W. Murphy, K.H. Berry, T. Edwards, A.M. McLuckie
2007, Chelonian Conservation and Biology (6) 229-251
In the 1994 Recovery Plan for the Mojave population of the desert tortoise, Gopherus agassizii, the US Fish and Wildlife Service established 6 recovery units by using the best available data on habitat use, behavior, morphology, and genetics. To further assess the validity of the recovery units, we analyzed genetic...
Monitoring mangrove forest dynamics of the Sundarbans in Bangladesh and India using multi-temporal satellite data from 1973 to 2000
S. Giri, Bruce Pengra, Z. Zhu, A. Singh, L.L. Tieszen
2007, Estuarine, Coastal and Shelf Science (73) 91-100
Mangrove forests in many parts of the world are declining at an alarming rate—possibly even more rapidly than inland tropical forests. The rate and causes of such changes are not known. The forests themselves are dynamic in nature and are undergoing constant changes due to both natural and anthropogenic forces....
Probabilistic prediction models for aggregate quarry siting
G.R. Robinson Jr., P.M. Larkins
2007, Natural Resources Research (16) 135-146
Weights-of-evidence (WofE) and logistic regression techniques were used in a GIS framework to predict the spatial likelihood (prospectivity) of crushed-stone aggregate quarry development. The joint conditional probability models, based on geology, transportation network, and population density variables, were defined using quarry location and time of development data for the New...
A land-cover map for South and Southeast Asia derived from SPOT-VEGETATION data
H.-J. Stibig, A.S. Belward, P.S. Roy, U. Rosalina-Wasrin, S. Agrawal, P.K. Joshi, Hildanus, R. Beuchle, S. Fritz, S. Mubareka, S. Giri
2007, Journal of Biogeography (34) 625-637
Aim Our aim was to produce a uniform ‘regional’ land-cover map of South and Southeast Asia based on ‘sub-regional’ mapping results generated in the context of the Global Land Cover 2000 project.Location The ‘region’ of tropical and sub-tropical South and Southeast Asia stretches from the Himalayas and the southern border...
Developing a flood monitoring system from remotely sensed data for the Limpopo basin
K.O. Asante, R.D. Macuacua, G. A. Artan, R.W. Lietzow, J. P. Verdin
2007, IEEE Transactions on Geoscience and Remote Sensing (45) 1709-1714
This paper describes the application of remotely sensed precipitation to the monitoring of floods in a region that regularly experiences extreme precipitation and flood events, often associated with cyclonic systems. Precipitation data, which are derived from spaceborne radar aboard the National Aeronautics and Space Administration's Tropical Rainfall Measuring Mission and...
Reconstructing sediment age profiles from historical bathymetry changes in San Pablo Bay, California
Shawn A. Higgins, Bruce E. Jaffe, Christopher C. Fuller
2007, Estuarine, Coastal and Shelf Science (73) 165-174
Sediment age profiles reconstructed from a sequence of historical bathymetry changes are used to investigate the subsurface distribution of historical sediments in a subembayment of the San Francisco Estuary. Profiles are created in a grid-based GIS modeling program that stratifies historical...
California red-legged frog (Rana draytonii) movement and habitat use: Implications for conservation
G. M. Fellers, P.M. Kleeman
2007, Journal of Herpetology (41) 276-286
Nonbreeding habitats are critically important for Rana draytonii, especially for individuals that breed in temporary bodies of water. We radiotracked 123 frogs to evaluate seasonal habitat use. Individual frogs were continuously tracked for up to 16 months. Some individuals remained at breeding ponds all year, but...
Lithium contents and isotopic compositions of ferromanganese deposits from the global ocean
L.-H. Chan, J.R. Hein
2007, Deep-Sea Research Part II: Topical Studies in Oceanography (54) 1147-1162
To test the feasibility of using lithium isotopes in marine ferromanganese deposits as an indicator of paleoceanographic conditions and seawater composition, we analyzed samples from a variety of tectonic environments in the global ocean. Hydrogenetic, hydrothermal, mixed hydrogenetic–hydrothermal, and hydrogenetic–diagenetic samples were...
Stress does not inhibit induced vitellogenesis in juvenile rainbow trout
A.R. Schwindt, G.W. Feist, C.B. Schreck
2007, Environmental Biology of Fishes (80) 453-463
Vitellogenin (Vtg) is a widely used biomarker for xenoestrogen exposure in male fishes. In female fishes Vtg can be negatively affected by stress independent of declines in estrogen. However, few data are available on the effect of stress in male fish abnormally producing Vtg, such as when exposed to xenoestrogens....
Cosmogenic 10Be and 36Cl geochronology of offset alluvial fans along the northern Death Valley fault zone: Implications for transient strain in the eastern California shear zone
K.L. Frankel, K.S. Brantley, J.F. Dolan, R.C. Finkel, R.E. Klinger, J.R. Knott, M. N. Machette, L.A. Owen, F. M. Phillips, J. L. Slate, B.P. Wernicke
2007, Journal of Geophysical Research B: Solid Earth (112)
The northern Death Valley fault zone (NDVFZ) has long been recognized as a major right-lateral strike-slip fault in the eastern California shear zone (ECSZ). However, its geologic slip rate has been difficult to determine. Using high-resolution digital topographic imagery and terrestrial cosmogenic nuclide dating, we present the first geochronologically determined...
Quantifying the media bias in intensity surveys: Lessons from the 2001 Bhuj, India, earthquake
S. E. Hough, P. Pande
2007, Bulletin of the Seismological Society of America (97) 638-645
Many seismologists have looked at the 26 January 2001 Bhuj earthquake as a key modern calibration event that could be used to improve estimates of magnitudes of large historic mainshocks in stable continental regions. Since no instrumental data are available for important historic events such as the 1819 Allah Bund,...
Occurrence and nest survival of four thrush species on a managed central Appalachian forest
R.L. Dellinger, P.B. Wood, P.D. Keyser
2007, Forest Ecology and Management (243) 248-258
The wood thrush (Hylocichla mustelina Gmelin) is a species of concern in the central Appalachians, and is sympatric there with three related species, the American robin (Turdus migratorius Linnaeus), hermit thrush (Catharus guttatus Pallas), and veery (Catharus fuscescens Stephens). Our objectives were to quantify use of mature forests and areas...
