A revised burial dose estimation procedure for optical dating of youngand modern-age sediments
L.J. Arnold, R.G. Roberts, R.F. Galbraith, S.B. DeLong
2009, Quaternary Geochronology (4) 306-325
The presence of genuinely zero-age or near-zero-age grains in modern-age and very young samples poses a problem for many existing burial dose estimation procedures used in optical (optically stimulated luminescence, OSL) dating. This difficulty currently necessitates consideration of relatively simplistic and statistically inferior age models. In this study, we investigate...
Seasonal shifts in shelter and microhabitat use of drymarchon couperi (eastern indigo snake) in Georgia
N.L. Hyslop, R.J. Cooper, J.M. Meyers
2009, Copeia (2009) 458-464
Drymarchon couperi (Eastern Indigo Snake), a threatened species of the southeastern Coastal Plain of the United States, has experienced population declines because of extensive habitat loss and degradation across its range. In Georgia and northern Florida, the species is associated with longleaf pine habitats that support Gopherus polyphemus (Gopher Tortoise)...
Water quality analysis of groundwater in crystalline basement rocks, Northern Ghana
Y.S. Anku, B. Banoeng-Yakubo, D.K. Asiedu, S.M. Yidana
2009, Environmental Geology (58) 989-997
Hydrochemical data are presented for groundwater samples, collected from fractured aquifers in parts of northern Ghana. The data was collected to assess the groundwater suitability for domestic and agricultural use. Results of the study reveal that the pH of the groundwater in the area is slightly acidic to slightly alkaline....
Vegetation classification and distribution mapping report: Mesa Verde National Park
Kathryn A. Thomas, Monica L. McTeague, Lindsay Ogden, M. Lisa Floyd, Keith Schulz, Beverly A. Friesen, Tammy S. Fancher, Robert G. Waltermire, Anne Cully
2009, Natural Resource Report NPS/SCPN/NRR—2009/112
The classification and distribution mapping of the vegetation of Mesa Verde National Park (MEVE) and surrounding environment was achieved through a multi-agency effort between 2004 and 2007. The National Park Service’s Southern Colorado Plateau Network facilitated the team that conducted the work, which comprised the U.S. Geological Survey’s Southwest Biological...
Spatial and temporal distributions of Martian north polar cold spots before, during, and after the global dust storm of 2001
C. Cornwall, T.N. Titus
2009, Journal of Geophysical Research E: Planets (114)
In the 1970s, Mariner and Viking observed features in the Mars northern polar region that were a few hundred kilometers in diameter with 20 fj,m brightness temperatures as low as 130 K (considerably below C02 ice sublimation temperatures). Over the past decade, studies have shown that these areas (commonly called...
A simplified water temperature model for the Colorado River below Glen Canyon Dam
S.A. Wright, C.R. Anderson, N. Voichick
2009, River Research and Applications (25) 675-686
Glen Canyon Dam, located on the Colorado River in northern Arizona, has affected the physical, biological and cultural resources of the river downstream in Grand Canyon. One of the impacts to the downstream physical environment that has important implications for the aquatic ecosystem is the transformation of the thermal regime...
Geomorphology, stability and mobility of the Currituck slide
J. Locat, H. Lee, Uri S. ten Brink, D. Twichell, E. Geist, M. Sansoucy
2009, Marine Geology (264) 28-40
Over the last 100,000??years, the U.S. Atlantic continental margin has experienced various types of mass movements some of which are believed to have taken place at times of low sea level. At one of these times of low sea level a significant trigger caused a major submarine mass movement off...
Uniform California earthquake rupture forecast, version 2 (UCERF 2)
E. H. Field, T. E. Dawson, K.R. Felzer, A.D. Frankel, V. Gupta, T.H. Jordan, T. Parsons, M.D. Petersen, R.S. Stein, R. J. Weldon, C.J. Wills
2009, Bulletin of the Seismological Society of America (99) 2053-2107
The 2007 Working Group on California Earthquake Probabilities (WGCEP, 2007) presents the Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2). This model comprises a time-independent (Poisson-process) earthquake rate model, developed jointly with the National Seismic Hazard Mapping Program and a time-dependent earthquake-probability model, based on recent earthquake rates and...
Calibration of an estuarine sediment transport model to sediment fluxes as an intermediate step for simulation of geomorphic evolution
N. K. Ganju, D. H. Schoellhamer
2009, Continental Shelf Research (29) 148-158
Modeling geomorphic evolution in estuaries is necessary to model the fate of legacy contaminants in the bed sediment and the effect of climate change, watershed alterations, sea level rise, construction projects, and restoration efforts. Coupled hydrodynamic and sediment transport models used for this purpose typically are calibrated to water level,...
Pore-throat sizes in sandstones, tight sandstones, and shales
Philip H. Nelson
2009, American Association of Petroleum Geologists Bulletin (93) 329-340
Pore-throat sizes in silidclastic rocks form a continuum from the submillimeter to the nanometer scale. That continuum is documented in this article using previously published data on the pore and pore-throat sizes of conventional reservoir rocks, tight-gas sandstones, and shales. For measures of central tendency (mean, mode, median), pore-throat sizes...
Incorporating both physical and kinetic limitations in quantifying dissolved oxygen flux to aquatic sediments
B.L. O’Connor, Miki Hondzo, J. W. Harvey
2009, Journal of Environmental Engineering (135) 1304-1314
Traditionally, dissolved oxygen (DO) fluxes have been calculated using the thin-film theory with DO microstructure data in systems characterized by fine sediments and low velocities. However, recent experimental evidence of fluctuating DO concentrations near the sediment-water interface suggests that turbulence and coherent motions control the mass transfer, and the surface...
Change in diel catchability of young-of-year yellow perch associated with establishment of dreissenid mussels
Martin A. Stapanian, Patrick M. Kocovsky, Jean V. Adams
2009, Freshwater Biology (54) 1593-1604
1. Non-native mussels have increased water clarity in many lakes and streams in North America and Europe. Diel variation in catchability of some fish species has been linked to visibility during survey trawls (used to measure escapement). 2. Water clarity increased in nearshore areas of western Lake Erie by the...
Internal tidal currents in the Gaoping (Kaoping) Submarine Canyon
I.-H. Lee, Y. #NAME? Wang, J.T. Liu, W.-S. Chuang, J. Xu
2009, Journal of Marine Systems (76) 397-404
Data from five separate field experiments during 2000-2006 were used to study the internal tidal flow patterns in the Gaoping (formerly spelled Kaoping) Submarine Canyon. The internal tides are large with maximum interface displacements of about 200??m and maximum velocities of over 100cm/s. They are characterized by a first-mode velocity...
Post-fledging movements of juvenile Common Mergansers (mergus merganser) in Alaska as inferred by satellite telemetry
John M. Pearce, Margaret R. Petersen
2009, Waterbirds (32) 133-137
We implanted satellite transmitters into eight juvenile Common Mergansers to investigate post-fledging movements from their natal river in southcentral Alaska. Subsequently, they moved widely throughout portions of western and southcentral Alaska up to 750 km from their natal areas during fall and winter months. Transmitters of two birds (one male...
High-frequency in situ optical measurements during a storm event: Assessing relationships between dissolved organic matter, sediment concentrations, and hydrologic processes
John Franco Saraceno, Brian A. Pellerin, Bryan D. Downing, Emmanuel Boss, Philip A. M. Bachand, Brian A. Bergamaschi
2009, Journal of Geological Research (114)
Dissolved organic matter (DOM) dynamics during storm events has received considerable attention in forested watersheds, but the extent to which storms impart rapid changes in DOM concentration and composition in highly disturbed agricultural watersheds remains poorly understood. In this study, we used identical in situ optical sensors for DOM fluorescence...
The contemporary cement cycle of the United States
A. Kapur, H. G. Van Oss, G. Keoleian, S.E. Kesler, A. Kendall
2009, Journal of Material Cycles and Waste Management (11) 155-165
A country-level stock and flow model for cement, an important construction material, was developed based on a material flow analysis framework. Using this model, the contemporary cement cycle of the United States was constructed by analyzing production, import, and export data for different stages of the cement cycle. The United...
Mesohaline submerged aquatic vegetation survey along the U.S. gulf of Mexico coast, 2001 and 2002: A salinity gradient approach
J.H. Merino, J. Carter, S.L. Merino
2009, Gulf of Mexico Science (27) 9-20
Distribution of marine submerged aquatic vegetation (SAV; i.e., seagrass) in the northern Gulf of Mexico coast has been documented, but there are nonmarine submersed or SAV species occurring in estuarine salinities that have not been extensively reported. We sampled 276 SAV beds along the gulf coast in Florida, Alabama, Mississippi,...
Spatial habitat use patterns of sea otters in coastal washington
K.L. Laidre, R.J. Jameson, E. Gurarie, S.J. Jeffries, H. Allen
2009, Journal of Mammalogy (90) 906-917
Sea otter (Enhydra lutris kenyoni) movements, home range, and activity budgets were described from data collected during very-high-frequency radiotelemetry studies of 75 individuals on the outer coast of Washington State between 1992 and 1999. Sea otters were located at least once per week from 22 accessible sites along the coast....
A multiscale analysis of coral reef topographic complexity using lidar-derived bathymetry
D.G. Zawada, J. C. Brock
2009, Journal of Coastal Research 6-15
Coral reefs represent one of the most irregular substrates in the marine environment. This roughness or topographic complexity is an important structural characteristic of reef habitats that affects a number of ecological and environmental attributes, including species diversity and water circulation. Little is known about the range of topographic complexity...
Remote monitoring of tamarisk defoliation and evapotranspiration following saltcedar leaf beetle attack
P.E. Dennison, P.L. Nagler, K. R. Hultine, E. P. Glenn, J.R. Ehleringer
2009, Remote Sensing of Environment (113) 1462-1472
Tamarisk (Tamarix spp.) has invaded riparian ecosystems throughout the Western United States, including significant portions of riparian ecosystems within U.S. National Parks and Monuments. Recently, the saltcedar leaf beetle (Diorhabda elongata) was released as a tamarisk biocontrol agent. Although initial releases have been monitored, no comprehensive program is currently in...
Diets of aquatic birds reflect changes in the Lake Huron ecosystem
Craig E. Hebert, D.V. Chip Weseloh, Abode Idrissi, Michael T. Arts, Edward F. Roseman
2009, Aquatic Ecosystem Health & Management (12) 37-44
Human activities have affected the Lake Huron ecosystem, in part, through alterations in the structure and function of its food webs. Insights into the nature of food web change and its ecological ramifications can be obtained through the monitoring of high trophic level predators such as aquatic birds. Often, food...
Extraction of lidar-based dune-crest elevations for use in examining the vulnerability of beaches to inundation during hurricanes
H.F. Stockdon, K.S. Doran, A. H. Sallenger Jr.
2009, Journal of Coastal Research 59-65
The morphology of coastal sand dunes plays an important role in determining how a beach will respond to a hurricane. Accurate measurements of dune height and position are essential for assessing the vulnerability of beaches to extreme coastal change during future landfalls. Lidar topographic surveys provide rapid, accurate, high-resolution datasets...
Characterization of Mars' seasonal caps using neutron spectroscopy
T.H. Prettyman, W. C. Feldman, T.N. Titus
2009, Journal of Geophysical Research E: Planets (114)
Mars' seasonal caps are characterized during Mars years 26 and 27 (April 2002 to January 2006) using data acquired by the 2001 Mars Odyssey Neutron Spectrometer. Time-dependent maps of the column abundance of seasonal CO 2 surface ice poleward of 60?? latitude in both hemispheres are determined from spatially deconvolved,...
Osprey: Worldwide sentinel species for assessing and monitoring environmental contamination in rivers, lakes, reservoirs, and estuaries
Robert A. Grove, Charles J. Henny, James L. Kaiser
2009, Journal of Toxicology and Environmental Health, Part B: Critical Reviews (12) 25-44
In the United States, many fish and wildlife species have been used nationwide to monitor environmental contaminant exposure and effects, including carcasses of the bald eagle (Haliaeetus leucocephalus), the only top avian predator regularly used in the past. Unfortunately, bald eagles are sensitive to investigator intrusion at the nest. Thus,...
Analysis of vegetation changes in Rock Creek Park, 1991-2007
Jeff S. Hatfield, Cairn Krafft
2009, Natural Resource Technical Report NPS/NCR/NCRO/NRTR--2009/001
Vegetation data collected at Rock Creek Park every 4 years during 1991-2007 were analyzed for differences among 3 regions within the park and among years. The variables measured and analyzed were percentage of twigs browsed, percentage of canopy cover, species richness of herbaceous plants, number of tree seedlings in each...
