Sediment delivery after a wildfire
Steven L. Reneau, D. Katzman, G.A. Kuyumjian, A. Lavine, D.V. Malmon
2007, Geology (35) 151-154
We use a record of sedimentation in a small reservoir within the Cerro Grande burn area, New Mexico, to document postfire delivery of ash, other fine-grained sediment carried in suspension within floods, and coarse-grained sediment transported as bedload over a five-year period. Ash...
Methane gas hydrate effect on sediment acoustic and strength properties
W.J. Winters, W.F. Waite, D.H. Mason, L.Y. Gilbert, I.A. Pecher
2007, Journal of Petroleum Science and Engineering (56) 127-135
To improve our understanding of the interaction of methane gas hydrate with host sediment, we studied: (1) the effects of gas hydrate and ice on acoustic velocity in different sediment types, (2) effect of different hydrate formation mechanisms on measured acoustic properties (3) dependence of shear strength on pore space...
Can modeling improve estimation of desert tortoise population densities?
K.E. Nussear, C.R. Tracy
2007, Ecological Applications (17) 579-586
The federally listed desert tortoise (Gopherus agassizii) is currently monitored using distance sampling to estimate population densities. Distance sampling, as with many other techniques for estimating population density, assumes that it is possible to quantify the proportion of animals available to be counted in any census. Because desert tortoises spend...
Latitudinal variation in population structure of wintering Pacific Black Brant
J.L. Schamber, James S. Sedinger, David H. Ward, K.R. Hagmeier
2007, Journal of Field Ornithology (78) 74-82
Latitudinal variation in population structure during the winter has been reported in many migratory birds, but has been documented in few species of waterfowl. Variation in environmental and social conditions at wintering sites can potentially influence the population dynamics of differential migrants. We examined latitudinal variation in sex and age...
Effects of intermittent flow and irradiance level on back reef Porites corals at elevated seawater temperatures
L.W. Smith, C. Birkeland
2007, Journal of Experimental Marine Biology and Ecology (341) 282-294
Corals inhabiting shallow back reef habitats are often simultaneously exposed to elevated seawater temperatures and high irradiance levels, conditions known to cause coral bleaching. Water flow in many tropical back reef systems is tidally influenced, resulting in semi-diurnal or diurnal flow patterns. Controlled experiments were conducted to test effects of...
In situ quantitative analysis of individual H2O-CO2 fluid inclusions by laser Raman spectroscopy
T. Azbej, M.J. Severs, B.G. Rusk, R.J. Bodnar
2007, Chemical Geology (237) 255-263
Raman spectral parameters for the Raman ??1 (1285??cm- 1) and 2??2 (1388??cm- 1) bands for CO2 and for the O-H stretching vibration band of H2O (3600??cm- 1) were determined in H2O-CO2 fluid inclusions. Synthetic fluid inclusions containing 2.5 to 50??mol% CO2 were analyzed at temperatures equal to or greater than...
Understanding Merapi-type volcanoes
M.A. Purbawinata, Antonius Ratdomopurbo, Surono, John S. Pallister, B. Luehr, Chris Newhall
2007, Eos, Transactions, American Geophysical Union (88) 5-5
"We have to understand volcano science to know what to monitor.” That simple statement by Antonius Ratdomopurbo, director of the Indonesian Center for Volcano Technology [Balai Penyelidikan dan Pengembangan‐Teknologi (BPPTK)],captured the spirit and content of a recent workshop about Merapi and Merapi‐type volcanoes.Merapi still is experiencing low levels of unrest,...
Trends in monitoring pharmaceuticals and personal-care products in the aquatic environment by use of passive sampling devices
G.A. Mills, B. Vrana, I. Allan, D.A. Alvarez, J.N. Huckins, R. Greenwood
2007, Analytical and Bioanalytical Chemistry (387) 1153-1157
The use of passive sampling in monitoring pharmaceuticals and personal-care products (PPCPs) in the aquatic environment is discussed. The utility of passive sampling methods for monitoring the fraction of heavy metals and the biologically available fraction of non-polar organic priority pollutants is recognized and these technologies are being used in...
Seismotectonic implications of sand blows in the southern Mississippi Embayment
R.T. Cox, A.A. Hill, D. Larsen, T. Holzer, S.L. Forman, T. Noce, C. Gardner, J. Morat
2007, Engineering Geology (89) 278-299
We explore seismically-induced sand blows from the southern Mississippi Embayment and their implications in resolving the question of near or distal epicentral source region. This was accomplished using aerial photography, field excavations, and cone penetration tests. Our analysis shows that three sand...
Wellsite, laboratory, and mathematical techniques for determining sorbed gas content of coals and gas shales utilizing well cuttings
K.D. Newell
2007, Natural Resources Research (16) 55-66
Drill cuttings can be used for desorption analyses but with more uncertainty than desorption analyses done with cores. Drill cuttings are not recommended to take the place of core, but in some circumstances, desorption work with cuttings can provide a timely and economic supplement to that of cores. The mixed...
Geologic and anthropogenic factors influencing karst development in the Frederick region of Maryland
D. K. Brezinski
2007, Environmental Geosciences (14) 31-48
Karst features pervade the outcrop belts of Triassic, Ordovician, and Cambrian rocks in the Frederick Valley region of Maryland's western Piedmont. Detailed stratigraphic analysis and geologic and karst mapping demonstrate that individual stratigraphic units have differing susceptibilities of karst feature creation. Although the Triassic Leesburg Member of the Bull Run...
Effects of season, rainfall, and hydrogeomorphic setting on mangrove tree growth in Micronesia
K. W. Krauss, B. D. Keeland, J. A. Allen, K. C. Ewel, Daniel J. Johnson
2007, Biotropica (39) 161-170
Seasonal patterns of tree growth are often related to rainfall, temperature, and relative moisture regimes. We asked whether diameter growth of mangrove trees in Micronesia, where seasonal changes are minimal, is continuous throughout a year or conforms to an annual cycle. We installed dendrometer bands on Sonneratia alba and Bruguiera...
Development of an SPE/CE method for analyzing HAAs
L. Zhang, P. D. Capel, R.M. Hozalski
2007, Journal - American Water Works Association (99) 83-94
A method to analyze haloacetic acids (HAAs) in drinking water was developed using a capillary electrophoresis (CE) ion analyzer for analyte separation and detection. The effects of background electrolyte (BGE) composition, sample injection approach, and on- and offcapillary preconcentration techniques on HAA peak resolution and method sensitivity were evaluated. The...
The reality of reserve growth
Mahendra K. Verma
2007, GEO ExPro (4) 34-35
No abstract available....
Heat transport in the Red Lake Bog, Glacial Lake Agassiz Peatlands
J.M. McKenzie, D. I. Siegel, Donald O. Rosenberry, P.H. Glaser, Clifford I. Voss
2007, Hydrological Processes (21) 369-378
We report the results of an investigation on the processes controlling heat transport in peat under a large bog in the Glacial Lake Agassiz Peatlands. For 2 years, starting in July 1998, we recorded temperature at 12 depth intervals from 0 to 400 cm within a vertical peat profile at...
Waveform inversion of volcano-seismic signals for an extended source
M. Nakano, Hiroyuki Kumagai, B. Chouet, P. Dawson
2007, Journal of Geophysical Research B: Solid Earth (112)
[1] We propose a method to investigate the dimensions and oscillation characteristics of the source of volcano-seismic signals based on waveform inversion for an extended source. An extended source is realized by a set of point sources distributed on a grid surrounding the centroid of...
Three-dimensional P-wave velocity structure derived from local earthquakes at the Katmai group of volcanoes, Alaska
A.D. Jolly, S.C. Moran, S.R. McNutt, D.B. Stone
2007, Journal of Volcanology and Geothermal Research (159) 326-342
The three-dimensional P-wave velocity structure beneath the Katmai group of volcanoes is determined by inversion of more than 10,000 rays from over 1000 earthquakes recorded on a local 18 station short-period network between September 1996 and May 2001. The inversion is well constrained from sea level to about 6 km below...
Effects of precommercial thinning on snowshoe hares in Maine
J.A. Homyack, D.J. Harrison, W.B. Krohn
2007, Journal of Wildlife Management (71) 4-13
Snowshoe hares (Lepus americanus) are an important prey species and a dominant herbivore across much of their North American range, and researchers have questioned the influences of forestry practices that alter habitat for hares and the potential community-level effects on carnivores. We examined the effects of precommercial thinning (PCT) from...
Neoproterozoic diamictite-cap carbonate succession and δ13C chemostratigraphy from eastern Sonora, Mexico
Frank A. Corsetti, John H. Stewart, James W. Hagadorn
2007, Chemical Geology (237) 147-160
Despite the occurrence of Neoproterozoic strata throughout the southwestern U.S. and Sonora, Mexico, glacial units overlain by enigmatic cap carbonates have not been well-documented south of Death Valley, California. Here, we describe in detail the first glaciogenic diamictite and cap carbonate succession from Mexico, found in the Cerro Las Bolas...
Comparison of evapotranspiration rates for flatwoods and ridge citrus
X. Jia, A. Swancar, J.M. Jacobs, M.D. Dukes, K. Morgan
2007, Transactions of the ASABE (50) 83-94
Florida citrus groves are typically grown in two regions of the state: flatwoods and ridge. The southern flatwoods citrus area has poorly drained fine textured sands with low organic matter in the shallow root zone. Ridge citrus is located in the northern ridge citrus zone and has fine to coarse...
Characterising reef fish populations and habitats within and outside the US Virgin Islands Coral Reef National Monument: A lesson in marine protected area design
Mark E. Monaco, A. M. Friedlander, Chris Caldow, J.D. Christensen, C. Rogers, J. Beets, J. Miller, Rafe Boulon
2007, Fisheries Management and Ecology (14) 33-40
Marine protected areas are an important tool for management of marine ecosystems. Despite their utility, ecological design criteria are often not considered or feasible to implement when establishing protected areas. In 2001, the Virgin Islands Coral Reef National Monument (VICRNM) in St John, US Virgin Islands was established by Executive...
Inflammatory reaction to fabric collars from percutaneous antennas attached to intracoelomic radio transmitters implanted in harlequin ducks (Histrionicus histrionicus)
Daniel M. Mulcahy, K.A. Burek, Daniel Esler
2007, Journal of Avian Medicine and Surgery (21) 13-21
In wild birds implanted intracoelomically with radio transmitters, a synthetic fabric collar placed around the base of a percutaneous antenna is believed to function as a barrier to contamination of the coelom. We examined 13 fabric collars recovered from percutaneous antennas of radio transmitters implanted intracoelomically in harlequin ducks (Histrionicus...
Age and trophic position dominate bioaccumulation of mercury and organochlorines in the food web of Lake Washington
J.K. McIntyre, D.A. Beauchamp
2007, Science of the Total Environment (372) 571-584
Understanding the mechanisms of bioaccumulation in food webs is critical to predicting which food webs are at risk for higher rates of bioaccumulation that endanger the health of upper-trophic predators, including humans. Mercury and organochlorines were measured concurrently with stable isotopes of nitrogen and carbon in key fishes and invertebrates...
Can parasites be indicators of free-living diversity? Relationships between species richness and the abundance of larval trematodes and of local benthos and fishes
R. F. Hechinger, K. D. Lafferty, T.C. Huspeni, A.J. Brooks, A. M. Kuris
2007, Oecologia (151) 82-92
Measuring biodiversity is difficult. This has led to efforts to seek taxa whose species richness correlates with the species richness of other taxa. Such indicator taxa could then reduce the time and cost of assessing the biodiversity of the more extensive community. The search for species richness correlations has yielded...
Linking occurrence and fitness to persistence: Habitat-based approach for endangered Greater Sage-Grouse
Cameron L. Aldridge, Mark S. Boyce
2007, Ecological Applications (17) 508-526
Detailed empirical models predicting both species occurrence and fitness across a landscape are necessary to understand processes related to population persistence. Failure to consider both occurrence and fitness may result in incorrect assessments of habitat importance leading to inappropriate management strategies. We took a two-stage approach to identifying critical nesting...
