Does sulphate enrichment promote the expansion of Typha domingensis (cattail) in the Florida Everglades?
S. Li, I.A. Mendelssohn, Chen Hao, W. H. Orem
2009, Freshwater Biology (54) 1909-1923
1. The expansion of Typha domingensis into areas once dominated by Cladium jamaicense in the Florida Everglades has been attributed to altered hydrology and phosphorus enrichment, although increased concentrations of sulphate and phosphorus often coincide. The potential importance of hydrogen sulphide produced from sulphate in the expansion of Typha has...
Comparison of alternative representations of hydraulic-conductivity anisotropy in folded fractured-sedimentary rock: Modeling groundwater flow in the Shenandoah Valley (USA)
R. M. Yager, C.I. Voss, S. Southworth
2009, Hydrogeology Journal (17) 1111-1131
A numerical representation that explicitly represents the generalized three-dimensional anisotropy of folded fractured-sedimentary rocks in a groundwater model best reproduces the salient features of the flow system in the Shenandoah Valley, USA. This conclusion results from a comparison of four alternative representations of anisotropy in which the hydraulic-conductivity tensor...
Potential habitat distribution for the freshwater diatom Didymosphenia geminata in the continental US
S. Kumar, S. A. Spaulding, T.J. Stohlgren, K.A. Hermann, T.S. Schmidt, L.L. Bahls
2009, Frontiers in Ecology and the Environment (7) 415-420
The diatom Didymosphenia geminata is a single-celled alga found in lakes, streams, and rivers. Nuisance blooms of D geminata affect the diversity, abundance, and productivity of other aquatic organisms. Because D geminata can be transported by humans on waders and other gear, accurate spatial prediction of habitat suitability is urgently...
Monitoring urban subsidence based on SAR lnterferometric point target analysis
Y. Zhang, Jiahua Zhang, W. Gong, Z. Lu
2009, Acta Geodaetica et Cartographica Sinica (38) 482-493
lnterferometric point target analysis (IPTA) is one of the latest developments in radar interferometric processing. It is achieved by analysis of the interferometric phases of some individual point targets, which are discrete and present temporarily stable backscattering characteristics, in long temporal series of interferometric SAR images. This paper analyzes the...
Co-seismic ruptures of the 12 May 2008, Ms 8.0 Wenchuan earthquake, Sichuan: East-west crustal shortening on oblique, parallel thrusts along the eastern edge of Tibet
J. Liu-Zeng, Z. Zhang, L. Wen, P. Tapponnier, Jielun Sun, X. Xing, G. Hu, Q. Xu, L. Zeng, L. Ding, C. Ji, K.W. Hudnut, J. van der Woerd
2009, Earth and Planetary Science Letters (286) 355-370
The Ms 8.0, Wenchuan earthquake, which devastated the mountainous western rim of the Sichuan basin in central China, produced a surface rupture over 200??km-long with oblique thrust/dextral slip and maximum scarp heights of ~ 10??m. It thus ranks as one of the world's largest continental mega-thrust events in the last...
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...
THEMIS high-resolution digital terrain: Topographic and thermophysical mapping of Gusev Crater, Mars
G.E. Cushing, T.N. Titus, L.A. Soderblom, R. L. Kirk
2009, Journal of Geophysical Research E: Planets (114)
We discuss a new technique to generate high-resolution digital terrain models (DTMs) and to quantitatively derive and map slope-corrected thermophysical properties such as albedo, thermal inertia, and surface temperatures. This investigation is a continuation of work started by Kirk et al. (2005), who empirically deconvolved Thermal Emission Imaging System (THEMIS)...
Tsunamis and splay fault dynamics
J. Wendt, D. D. Oglesby, E.L. Geist
2009, Geophysical Research Letters (36)
The geometry of a fault system can have significant effects on tsunami generation, but most tsunami models to date have not investigated the dynamic processes that determine which path rupture will take in a complex fault system. To gain insight into this problem, we use the 3D finite element method...
Lysimetric evaluation of simplified surface energy balance approach in the Texas high plains
P.H. Gowda, G.B. Senay, T.A. Howell, T.H. Marek
2009, Applied Engineering in Agriculture (25) 665-669
Numerous energy balance (EB) algorithms have been developed to make use of remote sensing data to estimate evapotranspiration (ET) regionally. However, most EB models are complex to use and efforts are being made to simplify procedures mainly through the scaling of reference ET. The Simplified Surface Energy Balance (SSEB) is...
Dynamics of national forests assessed using the Landsat record: Case studies in eastern United States
C. Huang, S.N. Goward, K. Schleeweis, N. Thomas, J. G. Masek, Z. Zhu
2009, Remote Sensing of Environment (113) 1430-1442
The national forests (NFs) in the United States are protected areas managed for multiple purposes, and therefore are subject to both natural and anthropogenic disturbances. Monitoring forest changes arising from such disturbances and the post-disturbance recovery processes is essential for assessing the conditions of the NFs and the effectiveness...
Rapid middle Miocene collapse of the Mesozoic orogenic plateau in north-central Nevada
Joseph P. Colgan, Christopher D. Henry
2009, International Geology Review (51) 920-961
The modern Sierra Nevada and Great Basin were likely the site of a high-elevation orogenic plateau well into Cenozoic time, supported by crust thickened during Mesozoic shortening. Although crustal thickening at this scale can lead to extension, the relationship between Mesozoic shortening and subsequent formation of the Basin and Range...
Patterns and determinants of mammal species occurrence in India
K.K. Karanth, J.D. Nichols, J.E. Hines, K. U. Karanth, N.L. Christensen
2009, Journal of Applied Ecology (46) 1189-1200
Many Indian mammals face range contraction and extinction, but assessments of their population status are hindered by the lack of reliable distribution data and range maps. 2. We estimated the current geographical ranges of 20 species of large mammals by applying occupancy models to data from country-wide expert. We modelled...
Relative importance of habitat area and isolation for bird occurrence patterns in a naturally patchy landscape
T.L. Wilson, E.J. Johnson, J.A. Bissonette
2009, Landscape Ecology (24) 351-360
There is debate among ecologists about whether total habitat area or patch arrangement contributes most to population and/or community responses to fragmented or patchy landscapes. We tested the relative effects of patch area and isolation for predicting bird occurrence in a naturally patchy landscape in the Bear River Mountains of...
Environmental correlates of breeding in the Crested Caracara (Caracara cheriway)
J. L. Morrison, Kyle E. Pias, J.B. Cohen, D.H. Catlin
2009, The Auk (126) 755-764
We evaluated the influence of weather on reproduction of the Crested Caracara (Caracara cheriway) in an agricultural landscape in south-central Florida. We used a mixed logistic-regression modeling approach within an information-theoretic framework to examine the influence of total rainfall, rainfall frequency, and temperature on the number of breeding pairs, timing...
Distribution and postbreeding environmental relationships of Northern leopard frogs (Rana [Lithobates] pipiens) in Washington
S.S. Germaine, D.W. Hays
2009, Western North American Naturalist (69) 537-547
Northern leopard frogs (Rana [Lithobates] pipiens) are considered sensitive, threatened, or endangered in all western states and western Canadian provinces. Historically present in eastern Washington in 6 major river drainages, leopard frogs are now only known to occur at 2 localized areas in the Crab Creek drainage in Grant County....
Geochemical evidence for African dust and volcanic ash inputs to terra rossa soils on carbonate reef terraces, northern Jamaica, West Indies
D.R. Muhs, J. R. Budahn
2009, Quaternary International (196) 13-35
The origin of red or reddish-brown, clay-rich, "terra rossa" soils on limestone has been debated for decades. A traditional qualitative explanation for their formation has been the accumulation of insoluble residues as the limestone is progressively dissolved over time. However, this mode of formation often requires unrealistic or impossible amounts...
Controls on groundwater flow in the Bengal Basin of India and Bangladesh: Regional modeling analysis
H.A. Michael, C.I. Voss
2009, Hydrogeology Journal (17) 1561-1577
Groundwater for domestic and irrigation purposes is produced primarily from shallow parts of the Bengal Basin aquifer system (India and Bangladesh), which contains high concentrations of dissolved arsenic (exceeding worldwide drinking water standards), though deeper groundwater is generally low in arsenic. An essential first step for determining sustainable management of...
Holocene climate on the Modoc Plateau, northern California, USA: The view from Medicine Lake
Scott W. Starratt
2009, Hydrobiologia (631) 197-211
Medicine Lake is a small (165 ha), relatively shallow (average 7.3 m), intermediate elevation (2,036 m) lake located within the summit caldera of Medicine Lake volcano, Siskiyou County, California, USA. Sediment cores and high-resolution bathymetric and seismic reflection data were collected from the lake during the fall of 1999 and 2000. Sediments were...
SToRM: A numerical model for environmental surface flows
Francisco J. Simoes
2009, Conference Paper, 33rd IAHR Congress: Water Engineering for a Sustainable Environment
SToRM (System for Transport and River Modeling) is a numerical model developed to simulate free surface flows in complex environmental domains. It is based on the depth-averaged St. Venant equations, which are discretized using unstructured upwind finite volume methods, and contains both steady and unsteady solution techniques. This article provides...
Dynamic modeling of nitrogen losses in river networks unravels the coupled effects of hydrological and biogeochemical processes
Richard B. Alexander, J.K. Bohlke, Elizabeth W. Boyer, Mark B. David, Judson W. Harvey, Patrick J. Mulholland, Sybil P. Seitzinger, Craig R. Tobias, Christina Tonitto, Wilfred M. Wollheim
2009, Biogeochemistry (93) 91-116
The importance of lotic systems as sinks for nitrogen inputs is well recognized. A fraction of nitrogen in streamflow is removed to the atmosphere via denitrification with the remainder exported in streamflow as nitrogen loads. At the watershed scale, there is a keen interest in understanding the factors that control...
Effects of fire temperature on the physical and chemical characteristics of the ash from two plots of Cork oak (Quercus Suber)
X. Ubeda, P. Pereira, L. Outeiro, D.A. Martin
2009, Land Degradation and Development (20) 589-608
Cork oak, (Quercus suber) is widely distributed in the Mediterranean region, an area subject to frequent fires. The ash produced by burning can have impacts on the soil status and water resources that can differ according to the temperature reached during fire and the characteristics of the litter, defined as...
Genetic conservation and paddlefish propagation
Brian L. Sloss, Robert A. Klumb, Edward J. Heist
2009, American Fisheries Society Symposium (66) 327
The conservation of genetic diversity of our natural resources is overwhelmingly one of the central foci of 21st century management practices. Three recommendations related to the conservation of paddlefish Polyodon spathula genetic diversity are to (1) identify genetic diversity at both nuclear and mitochondrial DNA loci using a suggested list...
Deer carcass decomposition and potential scavenger exposure to chronic wasting disease
C.S. Jennelle, M.D. Samuel, C.A. Nolden, E.A. Berkley
2009, Journal of Wildlife Management (73) 655-662
Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy afflicting the Cervidae family in North America, causing neurodegeneration and ultimately death. Although there are no reports of natural cross-species transmission of CWD to noncervids, infected deer carcasses pose a potential risk of CWD exposure for other animals. We placed 40...
Petrogenesis of basaltic volcanic rocks from the Pribilof Islands, Alaska, by melting of metasomatically enriched depleted lithosphere, crystallization differentiation, and magma mixing
J.M. Chang, T.C. Feeley, M.R. Deraps
2009, Journal of Petrology (50) 2249-2286
The Pribilof Islands, Alaska, are located in the Bering Sea in a continental intraplate setting. In this study we examine the petrology and geochemistry of volcanic rocks from St. Paul (0??54-0??003 Ma) and St. George (2??8-1??4 Ma) Islands, the two largest Pribilof Islands. Rocks from St. George can be divided...
Disease, predation and demography: Assessing the impacts of bovine tuberculosis on African buffalo by monitoring at individual and population levels
P.C. Cross, D.M. Heisey, J.A. Bowers, C.T. Hay, J. Wolhuter, P. Buss, M. Hofmeyr, A.L. Michel, Roy G. Bengis, T.L.F. Bird, Johan T. du Toit, W.M. Getz
2009, Journal of Applied Ecology (46) 467-475
SummaryUnderstanding the effects of disease is critical to determining appropriate management responses, but estimating those effects in wildlife species is challenging. We used bovine tuberculosis (BTB) in the African buffalo Syncerus caffer population of Kruger National Park, South Africa, as a case study to highlight the issues associated with estimating...
