Sap flux-scaled transpiration by tamarisk (Tamarix spp.) before, during and after episodic defoliation by the saltcedar leaf beetle (Diorhabda carinulata)
K. R. Hultine, P.L. Nagler, K. Morino, S.E. Bush, K.G. Burtch, P.E. Dennison, E. P. Glenn, J.R. Ehleringer
2010, Agricultural and Forest Meteorology (150) 1467-1475
The release of the saltcedar beetle (Diorhabda carinulata) has resulted in the periodic defoliation of tamarisk (Tamarix spp.) along more than 1000 river km in the upper Colorado River Basin and is expected to spread along many other river reaches throughout the upper basin, and possibly into the lower Colorado...
Regional estimates of ecological services derived from U.S. Department of Agriculture conservation programs in the Mississippi Alluvial Valley
Stephen P. Faulkner, Michael J. Baldwin, Wylie C. Barrow, Hardin Waddle, Bobby D. Keeland, Susan C. Walls, Dale James, Tom Moorman
2010, Report, NRCS
The Mississippi Alluvial Valley (MAV) is the Nation?s largest floodplain and this once predominantly forested ecosystem provided significant habitat for a diverse flora and fauna, sequestered carbon in trees and soil, and stored floodwater, sediments, and nutrients within the floodplain. This landscape has been substantially altered by the conversion of...
Landscape effects on diets of two canids in Northwestern Texas: A multinomial modeling approach
P.R. Lemons, J.S. Sedinger, M.P. Herzog, P. S. Gipson, R.L. Gilliland
2010, Journal of Mammalogy (91) 66-78
Analyses of feces, stomach contents, and regurgitated pellets are common techniques for assessing diets of vertebrates and typically contain more than 1 food item per sampling unit. When analyzed, these individual food items have traditionally been treated as independent, which represents pseudoreplication. When food types are recorded as present or...
Early observations on an emerging Great Lakes invader Hemimysis anomala in Lake Ontario
Maureen G. Walsh, Brian F. Lantry, Brent Boscarino, Kelly Bowen, Jocelyn Gerlofsma, Ted Schaner, Richard Back, Jennifer Questel, A. Garry Smythe, Roberta Cap, Michael Goehle, Bryan Young, Marc A. Chalupnicki, James H. Johnson, James E. McKenna
2010, Journal of Great Lakes Research (36) 499-504
Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on...
Seasonal groundwater contribution to crop-water use assessed with lysimeter observations and model simulations
Y. Luo, M. Sophocleous
2010, Journal of Hydrology (389) 325-335
Groundwater evaporation can play an important role in crop-water use where the water table is shallow. Lysimeters are often used to quantify the groundwater evaporation contribution influenced by a broad range of environmental factors. However, it is difficult for such field facilities, which are operated under limited conditions within limited...
Treated wastewater and Nitrate transport beneath irrigated fields near Dodge city, Kansas
M. Sophocleous, M.A. Townsend, F. Vocasek, Liwang Ma, K.C. Ashok
2010, Current Research in Earth Sciences (258) 1-31
Use of secondary-treated municipal wastewater for crop irrigation south of Dodge City, Kansas, where the soils are mainly of silty clay loam texture, has raised a concern that it has resulted in high nitratenitrogen concentrations (10-50 mg/kg) in the soil and deeper vadose zone, and also in the underlying deep...
Gypsies in the palace: Experimentalist's view on the use of 3-D physics-based simulation of hillslope hydrological response
A.L. James, Jeffery J. McDonnell, I. Tromp-Van Meerveld, N.E. Peters
2010, Hydrological Processes (24) 3878-3893
As a fundamental unit of the landscape, hillslopes are studied for their retention and release of water and nutrients across a wide range of ecosystems. The understanding of these near-surface processes is relevant to issues of runoff generation, groundwater-surface water interactions, catchment export of nutrients, dissolved organic carbon, contaminants (e.g....
A California statewide three-dimensional seismic velocity model from both absolute and differential times
G. Lin, C.H. Thurber, H. Zhang, E. Hauksson, P.M. Shearer, F. Waldhauser, T.M. Brocher, J. Hardebeck
2010, Bulletin of the Seismological Society of America (100) 225-240
We obtain a seismic velocity model of the California crust and uppermost mantle using a regional-scale double-difference tomography algorithm. We begin by using absolute arrival-time picks to solve for a coarse three-dimensional (3D) P velocity (VP) model with a uniform 30 km horizontal node spacing, which we then use as...
On the application of multilevel modeling in environmental and ecological studies
Song S. Qian, Thomas F. Cuffney, Ibrahim Alameddine, Gerard McMahon, Kenneth H. Reckhow
2010, Ecology (91) 355-361
This paper illustrates the advantages of a multilevel/hierarchical approach for predictive modeling, including flexibility of model formulation, explicitly accounting for hierarchical structure in the data, and the ability to predict the outcome of new cases. As a generalization of the classical approach, the multilevel modeling approach explicitly models the hierarchical...
Night sampling improves indices used for management of yellow perch in Lake Erie
P.M. Kocovsky, M.A. Stapanian, C.T. Knight
2010, Fisheries Management and Ecology (17) 10-18
Catch rate (catch per hour) was examined for age-0 and age-1 yellow perch, Perca flavescens (Mitchill), captured in bottom trawls from 1991 to 2005 in western Lake Erie: (1) to examine variation of catch rate among years, seasons, diel periods and their interactions; and (2) to determine whether sampling during...
Housing growth in and near United States protected areas limits their conservation value
V. C. Radeloff, S. I. Stewart, T. J. Hawbaker, U. Gimmi, A.M. Pidgeon, C.H. Flather, R. B. Hammer, D.P. Helmers
2010, Proceedings of the National Academy of Sciences of the United States of America (107) 940-945
Protected areas are crucial for biodiversity conservation because they provide safe havens for species threatened by land-use change and resulting habitat loss. However, protected areas are only effective when they stop habitat loss within their boundaries, and are connected via corridors to other wild areas. The effectiveness of protected areas...
Event-driven sediment flux in Hueneme and Mugu submarine canyons, southern California
J. P. Xu, P.W. Swarzenski, M. Noble, A.-C. Li
2010, Marine Geology (269) 74-88
Vertical sediment fluxes and their dominant controlling processes in Hueneme and Mugu submarine canyons off south-central California were assessed using data from sediment traps and current meters on two moorings that were deployed for 6 months during the winter of 2007. The maxima of total particulate flux, which reached as...
MTBE, TBA, and TAME attenuation in diverse hyporheic zones
James Landmeyer, Paul M. Bradley, D.A. Trego, K.G. Hale, J.E. Haas II
2010, Ground Water (48) 30-41
Groundwater contamination by fuel-related compounds such as the fuel oxygenates methyl tert-butyl ether (MTBE), tert-butyl alcohol (TBA), and tert-amyl methyl ether (TAME) presents a significant issue to managers and consumers of groundwater and surface water that receives groundwater discharge. Four sites were investigated on Long Island, New York, characterized by...
On the specification of structural equation models for ecological systems
James B. Grace, T. Michael Anderson, Han Olff, S.M. Scheiner
2010, Ecological Monographs (80) 67-87
The use of structural equation modeling (SEM) is often motivated by its utility for investigating complex networks of relationships, but also because of its promise as a means of representing theoretical concepts using latent variables. In this paper, we discuss characteristics of ecological theory and some of the challenges for...
Morphologic dating of fault scarps using airborne laser swath mapping (ALSM) data
G.E. Hilley, S. Delong, C. Prentice, K. Blisniuk, J.R. Arrowsmith Jr.
2010, Geophysical Research Letters (37)
Models of fault scarp morphology have been previously used to infer the relative age of different fault scarps in a fault zone using labor-intensive ground surveying. We present a method for automatically extracting scarp morphologic ages within high-resolution digital topography. Scarp degradation is modeled as a diffusive mass transport process...
In situ measurements of volatile aromatic hydrocarbon biodegradation rates in groundwater
I.M. Cozzarelli, B.A. Bekins, R.P. Eganhouse, E. Warren, H.I. Essaid
2010, Journal of Contaminant Hydrology (111) 48-64
Benzene and alkylbenzene biodegradation rates and patterns were measured using an in situ microcosm in a crude-oil contaminated aquifer near Bemidji, Minnesota. Benzene-D6, toluene, ethylbenzene, o-, m- and p-xylenes and four pairs of C3- and C4-benzenes were added to an in situ microcosm and studied over a 3-year period. The...
Model selection bias and Freedman's paradox
P.M. Lukacs, K.P. Burnham, David R. Anderson
2010, Annals of the Institute of Statistical Mathematics (62) 117-125
In situations where limited knowledge of a system exists and the ratio of data points to variables is small, variable selection methods can often be misleading. Freedman (Am Stat 37:152-155, 1983) demonstrated how common it is to select completely unrelated variables as highly "significant" when the number of data points...
Evaluation of aquifer heterogeneity effects on river flow loss using a transition probability framework
N.B. Engdahl, E. T. Vogler, G.S. Weissmann
2010, Water Resources Research (46)
River-aquifer exchange is considered within a transition probability framework along the Rio Grande in Albuquerque, New Mexico, to provide a stochastic estimate of aquifer heterogeneity and river loss. Six plausible hydrofacies configurations were determined using categorized drill core and wetland survey data processed through the TPROGS geostatistical package. A base...
Patterns of Tamarix water use during a record drought
J.B. Nippert, J.J. Butler Jr., Gerard J. Kluitenberg, Donald O. Whittemore, D. Arnold, S.E. Spal, J.K. Ward
2010, Oecologia (162) 283-292
During a record drought (2006) in southwest Kansas, USA, we assessed groundwater dynamics in a shallow, unconfined aquifer, along with plant water sources and physiological responses of the invasive riparian shrub Tamarix ramosissima. In early May, diel water table fluctuations indicated evapotranspirative consumption of groundwater by vegetation. During the summer...
Testing alternative models of climate-mediated extirpations
E.A. Beever, R.A.Y. Chris, P.W. Mote, J.L. Wilkening
2010, Ecological Applications (20) 164-178
Biotic responses to climate change will vary among taxa and across latitudes, elevational gradients, and degrees of insularity. However, due to factors such as phenotypic plasticity, ecotypic variation, and evolved tolerance to thermal stress, it remains poorly understood whether losses should be greatest in populations experiencing the greatest climatic change...
Exploring the limits of identifying sub-pixel thermal features using ASTER TIR data
R. Greg Vaughan, Laszlo P. Keszthelyi, Ashley G. Davies, David J. Schneider, Cheryl Jaworowski, Henry Heasler
2010, Journal of Volcanology and Geothermal Research (189) 225-237
Understanding the characteristics of volcanic thermal emissions and how they change with time is important for forecasting and monitoring volcanic activity and potential hazards. Satellite instruments view volcanic thermal features across the globe at various temporal and spatial resolutions. Thermal features that may be a precursor to a major eruption,...
Decadal-timescale estuarine geomorphic change under future scenarios of climate and sediment supply
N. K. Ganju, D. H. Schoellhamer
2010, Estuaries and Coasts (33) 15-29
Future estuarine geomorphic change, in response to climate change, sea-level rise, and watershed sediment supply, may govern ecological function, navigation, and water quality. We estimated geomorphic changes in Suisun Bay, CA, under four scenarios using a tidal-timescale hydrodynamic/sediment transport model. Computational expense and data needs were reduced using the morphological...
Long-term variability in Northern Hemisphere snow cover and associations with warmer winters
G.J. McCabe, D.M. Wolock
2010, Climatic Change (99) 141-153
A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published...
Silica-rich deposits and hydrated minerals at Gusev Crater, Mars: Vis-NIR spectral characterization and regional mapping
M.S. Rice, J.F. Bell III, E.A. Cloutis, A. Wang, S. W. Ruff, M.A. Craig, D.T. Bailey, J. R. Johnson, P.A. De Souza Jr., W. H. Farrand
2010, Icarus (205) 375-395
The Mars Exploration Rover (MER) Spirit has discovered surprisingly high concentrations of amorphous silica in soil and nodular outcrops in the Inner Basin of the Columbia Hills. In Pancam multispectral observations, we find that an absorption feature at the longest Pancam wavelength (1009 nm) appears to be characteristic of these...
Probable causes of increasing brucellosis in free-ranging elk of the Greater Yellowstone Ecosystem
Paul C. Cross, E.K. Cole, A. P. Dobson, W.H. Edwards, K.L. Hamlin, G. Luikart, A.D. Middleton, B.M. Scurlock, P.J. White
2010, Ecological Applications (20) 278-288
While many wildlife species are threatened, some populations have recovered from previous overexploitation, and data linking these population increases with disease dynamics are limited. We present data suggesting that free-ranging elk (Cervus elaphus) are a maintenance host for Brucella abortus in new areas of the Greater Yellowstone Ecosystem (GYE). Brucellosis...
