A quantitative evaluation of the iron-sulfur world and its relevance to life's origins
D.S. Ross
2008, Conference Paper, Astrobiology
The significance of Wa??chtersha??user's iron-sulfur world to the origin of life and the limits to its notional autocatalytic cycles are examined in kinetic simulations of the chain polymerization sequence primitive materials ??? amino acids ??? oligomers The simulations were run for the formation of all oligomers up to the 20-mer...
Fecal indicator bacteria and Salmonella in ponds managed as bird habitat, San Francisco Bay, California, USA
G.G. Shellenbarger, N.D. Athearn, John Y. Takekawa, A.B. Boehm
2008, Water Research (42) 2921-2930
Throughout the world, coastal resource managers are encouraging the restoration of previously modified coastal habitats back into wetlands and managed ponds for their ecosystem value. Because many coastal wetlands are adjacent to urban centers and waters used for human recreation, it is important to understand how wildlife can affect water...
Demographics of the spawning aggregations of four catostomid species in the Savannah River, South Carolina and Georgia, USA
T.B. Grabowski, N.L. Ratterman, J. Jeffery Isely
2008, Ecology of Freshwater Fish (17) 318-327
Differences in the life history strategies employed by otherwise ecologically similar species of a fish assemblage may be an important factor in the coexistence of these species and is an essential consideration in the conservation and management of these assemblages. We collected scales to determine age and growth of four...
Alternative feeding strategies and potential disease transmission in Wisconsin white-tailed deer
A.K. Thompson, M.D. Samuel, T.R. VanDeelen
2008, Journal of Wildlife Management (72) 416-421
We conducted experimental feeding using 3 feeding methods (pile, spread, trough) and 2 quantities (rationed, ad libitum) of shelled corn to compare deer activity and behavior with control sites and evaluate potential direct and indirect transmission of infectious disease in white-tailed deer (Odocoileus virginianus) in central Wisconsin, USA. Deer use...
Landslides triggered by the 8 October 2005 Kashmir earthquake
L.A. Owen, U. Kamp, G.A. Khattak, E. L. Harp, D. K. Keefer, M.A. Bauer
2008, Geomorphology (94) 1-9
The 8 October 2005 Kashmir earthquake triggered several thousand landslides. These were mainly rock falls and debris falls, although translational rock and debris slides also occurred. In addition, a sturzstrom (debris avalanche) comprising ??? 80??million m3 buried four villages and blocked streams to create two lakes. Although landsliding occurred throughout...
A rapid method for hydraulic profiling in unconsolidated formations
P. Dietrich, J.J. Butler Jr., K. Faiss
2008, Ground Water (46) 323-328
Information on vertical variations in hydraulic conductivity (K) can often shed much light on how a contaminant will move in the subsurface. The direct-push injection logger has been developed to rapidly obtain such information in shallow unconsolidated settings. This small-diameter tool consists of a short screen located just behind a...
Effects of turbulence on hydraulic heads and parameter sensitivities in preferential groundwater flow layers
W. Barclay Shoemaker, Kevin J. Cunningham, Eve L. Kuniansky, Joann F. Dixon
2008, Water Resources Research (44)
A conduit flow process (CFP) for the Modular Finite Difference Ground‐Water Flow model, MODFLOW‐2005, has been created by the U.S. Geological Survey. An application of the CFP on a carbonate aquifer in southern Florida is described; this application examines (1) the potential for turbulent groundwater flow and (2) the effects...
Reproductive ecology of Actinonaias ligamentina (Bivalvia:Unionidae) in a regulated river
K.R. Moles, J.B. Layzer
2008, Journal of the North American Benthological Society (27) 212-222
Factors affecting the reproductive success of freshwater mussels in lotic systems are poorly understood. Gravidity, fecundity, and fertilization success of Actinonaias ligamentina were examined at 4 sites along a 63-km reach of the Green River immediately below the Green River Dam, Kentucky. No gravid females were collected at the site...
Gas and gas hydrate distribution around seafloor seeps in Mississippi Canyon, Northern Gulf of Mexico, using multi-resolution seismic imagery
W.T. Wood, P. E. Hart, D. R. Hutchinson, N. Dutta, F. Snyder, R.B. Coffin, J.F. Gettrust
2008, Marine and Petroleum Geology (25) 952-959
To determine the impact of seeps and focused flow on the occurrence of shallow gas hydrates, several seafloor mounds in the Atwater Valley lease area of the Gulf of Mexico were surveyed with a wide range of seismic frequencies. Seismic data were acquired with a deep-towed, Helmholz resonator source (220-820...
Increasing shallow groundwater CO2 and limestone weathering, Konza Prairie, USA
G.L. Macpherson, J.A. Roberts, J.M. Blair, M.A. Townsend, D.A. Fowle, K. R. Beisner
2008, Geochimica et Cosmochimica Acta (72) 5581-5599
In a mid-continental North American grassland, solute concentrations in shallow, limestone-hosted groundwater and adjacent surface water cycle annually and have increased steadily over the 15-year study period, 1991-2005, inclusive. Modeled groundwater CO2, verified by measurements of recent samples, increased from 10-2.05 atm to 10-1.94 atm, about a 20% increase, from...
Recent extreme avalanches: Triggered by climate change?
C. Huggel, J. Caplan-Auerbach, Rick Wessels
2008, Eos, Transactions, American Geophysical Union (89) 469-470
On 25 September 2008, seismo meters operated by the Alaska Volcano Observatory (AVO) registered strong ground shaking. On the basis of previous experience with such large seismic signals, AVO personnel were able to rapidly identify the seismic event as an avalanche. Two days later, an AVO overflight of Iliamna volcano,...
Habitat relationships with fish assemblages in minimally disturbed Great Plains regions
John R. Fischer, C.P. Paukert
2008, Ecology of Freshwater Fish (17) 597-609
Effects of local environmental influences on the structure of fish assemblages were evaluated from 159 sites in two regions of the Great Plains with limited anthropogenic disturbance. These regions offered an opportunity to evaluate the structure and variation of streams and fish assemblages within the Great Plains. We used canonical...
Geochemical signature of land-based activities in Caribbean coral surface samples
N.G. Prouty, K.A. Hughen, J. Carilli
2008, Coral Reefs (27) 727-742
Anthropogenic threats, such as increased sedimentation, agrochemical run-off, coastal development, tourism, and overfishing, are of great concern to the Mesoamerican Caribbean Reef System (MACR). Trace metals in corals can be used to quantify and monitor the impact of these land-based activities. Surface coral samples from the MACR were investigated for...
Paired charcoal and tree-ring records of high-frequency Holocene fire from two New Mexico bog sites
Craig D. Allen, R. Scott Anderson, R.B. Jass, J.L. Toney, C.H. Baisan
2008, International Journal of Wildland Fire (17) 115-130
Two primary methods for reconstructing paleofire occurrence include dendrochronological dating of fire scars and stand ages from live or dead trees (extending back centuries into the past) and sedimentary records of charcoal particles from lakes and bogs, providing perspectives on fire history that can extend back for many thousands of...
Physical and chemical changes in the foreshore of an estuarine beach: Implications for viability and development of horseshoe crab Limulus polyphemus eggs
N.L. Jackson, D. R. Smith, K.F. Nordstrom
2008, Marine Ecology Progress Series (355) 209-218
Knowledge of conditions that favor development of eggs is important for management of species whose population growth is sensitive to early life history survival. Viability and development of the eggs of horseshoe crabs Limulus polyphemus on a sand and gravel beach were evaluated using data gathered on Delaware Bay, USA,...
Anthropogenic influences on the input and biogeochemical cycling of nutrients and mercury in Great Salt Lake, Utah, USA
D. Naftz, C. Angeroth, T. Kenney, B. Waddell, N. Darnall, S. Silva, C. Perschon, J. Whitehead
2008, Applied Geochemistry (23) 1731-1744
Despite the ecological and economic importance of Great Salt Lake (GSL), little is known about the input and biogeochemical cycling of nutrients and trace elements in the lake. In response to increasing public concern regarding anthropogenic inputs to the GSL ecosystem, the US Geological Survey (USGS) and US Fish and...
Predictions for an invaded world: A strategy to predict the distribution of native and non-indigenous species at multiple scales
D.A. Reusser, H. Lee II
2008, Conference Paper, ICES Journal of Marine Science
Habitat models can be used to predict the distributions of marine and estuarine non-indigenous species (NIS) over several spatial scales. At an estuary scale, our goal is to predict the estuaries most likely to be invaded, but at a habitat scale, the goal is to predict the specific locations within...
Evaluation of statistical treatments of left-censored environmental data using coincident uncensored data sets: I. Summary statistics
Ronald C. Antweiler, Howard E. Taylor
2008, Environmental Science & Technology (42) 3732-3738
The main classes of statistical treatment of below-detection limit (left-censored) environmental data for the determination of basic statistics that have been used in the literature are substitution methods, maximum likelihood, regression on order statistics (ROS), and nonparametric techniques. These treatments, along with using all instrument-generated data (even those below detection),...
Relative importance of natural disturbances and habitat degradation on snail kite population dynamics
J. Martin, W.M. Kitchens, Christopher E. Cattau, M.K. Oli
2008, Endangered Species Research (6) 25-39
Natural disturbances and habitat degradation are major factors influencing the dynamics and persistence of many wildlife populations, yet few large-scale studies have explored the relative influence of these factors on the dynamics and persistence of animal populations. We used longterm demographic data and matrix population models to examine the potential...
Late Pleistocene and Early Holocene lake-level fluctuations in the Lahontan Basin, Nevada: Implications for the distribution of archaeological sites
K.D. Adams, Thomas Goebel, K. Graf, G.M. Smith, A.J. Camp, R.W. Briggs, D. Rhode
2008, Geoarchaeology (23) 608-643
The Great Basin of the western U.S. contains a rich record of late Pleistocene and Holocene lake-level fluctuations as well as an extensive record of human occupation during the same time frame. We compare spatial-temporal relationships between these records in the Lahontan basin to consider whether lake-level fluctuations across the...
Assigning king eiders to wintering regions in the Bering Sea using stable isotopes of feathers and claws
S. Oppel, A.N. Powell
2008, Marine Ecology Progress Series (373) 149-156
Identification of wintering regions for birds sampled during the breeding season is crucial to understanding how events outside the breeding season may affect populations. We assigned king eiders captured on breeding grounds in northern Alaska to 3 broad geographic wintering regions in the Bering Sea using stable carbon and nitrogen...
Using the Model Coupling Toolkit to couple earth system models
J.C. Warner, N. Perlin, E.D. Skyllingstad
2008, Environmental Modelling and Software (23) 1240-1249
Continued advances in computational resources are providing the opportunity to operate more sophisticated numerical models. Additionally, there is an increasing demand for multidisciplinary studies that include interactions between different physical processes. Therefore there is a strong desire to develop coupled modeling systems that utilize existing models and allow efficient data...
Modelling the impact of wind stress and river discharge on Danshuei River plume
W.-C. Liu, W.-B. Chen, R. T. Cheng, M.-H. Hsu
2008, Applied Mathematical Modelling (32) 1255-1280
A three-dimensional, time-dependent, baroclinic, hydrodynamic and salinity model, UnTRIM, was performed and applied to the Danshuei River estuarine system and adjacent coastal sea in northern Taiwan. The model forcing functions consist of tidal elevations along the open boundaries and freshwater inflows from the main stream and major tributaries in the...
Littoral zones as sources of biodegradable dissolved organic carbon in lakes
E.G. Stets, J.B. Cotner
2008, Canadian Journal of Fisheries and Aquatic Sciences (65) 2454-2460
A survey of 12 lakes in Minnesota, USA, was conducted to examine the factors controlling variability in biodegradable dissolved organic carbon (BDOC) concentration. The principal question addressed was whether BDOC concentration was more strongly related to lake trophic status or morphometric parameters. BDOC concentration was determined by incubating filtered lake...
Transient deterministic shallow landslide modeling: Requirements for susceptibility and hazard assessments in a GIS framework
J. W. Godt, R.L. Baum, W. Z. Savage, D. Salciarini, W.H. Schulz, E. L. Harp
2008, Engineering Geology (102) 214-226
Application of transient deterministic shallow landslide models over broad regions for hazard and susceptibility assessments requires information on rainfall, topography and the distribution and properties of hillside materials. We survey techniques for generating the spatial and temporal input data for such models and present an example using a transient deterministic...
