An ecological risk assessment of the acute and chronic toxicity of the herbicide picloram to the threatened bull trout (salvelinus confluentus) and the rainbow trout (onchorhyncus mykiss)
J.F. Fairchild, K.P. Feltz, L.C. Sappington, A.L. Allert, K.J. Nelson, J. Valle
2009, Archives of Environmental Contamination and Toxicology (56) 761-769
We conducted acute and chronic toxicity studies of the effects of picloram acid on the threatened bull trout (Salvelinus confluentus) and the standard coldwater surrogate rainbow trout (Oncorhynchus mykiss). Juvenile fish were chronically exposed for 30 days in a proportional flow-through diluter to measured concentrations of 0,...
Frequency-domain Green's functions for radar waves in heterogeneous 2.5D media
K.J. Ellefsen, D. Croize, A.T. Mazzella, J.R. McKenna
2009, Geophysics (74)
Green's functions for radar waves propagating in heterogeneous 2.5D media might be calculated in the frequency domain using a hybrid method. The model is defined in the Cartesian coordinate system, and its electromagnetic properties might vary in the x- and z-directions, but not in the y-direction. Wave propagation in the...
Effects of simplifying fracture network representation on inert chemical migration in fracture-controlled aquifers
Tristan Wellman, Allen M. Shapiro, Mary C. Hill
2009, Water Resources Research (45)
[1] While it is widely recognized that highly permeable ‘large‐scale' fractures dominate chemical migration in many fractured aquifers, recent studies suggest that the pervasive ‘small‐scale’ fracturing once considered of less significance can be equally important for characterizing the spatial extent and residence time associated with transport processes....
Detecting declines in the abundance of a bull trout (Salvelinus confluentus) population: Understanding the accuracy, precision, and costs of our efforts
R. Al-Chokhachy, P. Budy, M. Conner
2009, Canadian Journal of Fisheries and Aquatic Sciences (66) 649-658
Using empirical field data for bull trout (Salvelinus confluentus), we evaluated the trade-off between power and sampling effort-cost using Monte Carlo simulations of commonly collected mark-recapture-resight and count data, and we estimated the power to detect changes in abundance across different time intervals. We also evaluated the effects of monitoring...
Factors influencing densities of non-indigenous species in the ballast water of ships arriving at ports in Puget Sound, Washington, United States
J.R. Cordell, D. J. Lawrence, N.C. Ferm, L.M. Tear, S.S. Smith, R.P. Herwig
2009, Aquatic Conservation: Marine and Freshwater Ecosystems (19) 322-343
Oceanographic characteristics and the presence of international shipping in Puget Sound, Washington, USA contribute to its vulnerability to non-indigenous species (NIS) invasions. To evaluate NIS arriving in ballast water, zooplankton was sampled in 380 ballast tanks of ships after they entered Puget Sound. Taxa were classified into a higher risk...
Low lower crustal velocity across Ethiopia: Is the Main Ethiopian Rift a narrow rift in a hot craton?
K.M. Keranen, S.L. Klemperer, J. Julia, J. F. Lawrence, A.A. Nyblade
2009, Geochemistry, Geophysics, Geosystems (10)
[1] The Main Ethiopian Rift (MER) is a classic narrow rift that developed in hot, weak lithosphere, not in the initially cold, thick, and strong lithosphere that would be predicted by common models of rift mode formation. Our new 1-D seismic velocity profiles from Rayleigh wave/receiver function joint inversion across...
A Viscoelastic earthquake simulator with application to the San Francisco Bay region
Fred F. Pollitz
2009, Bulletin of the Seismological Society of America (99) 1760-1785
Earthquake simulation on synthetic fault networks carries great potential for characterizing the statistical patterns of earthquake occurrence. I present an earthquake simulator based on elastic dislocation theory. It accounts for the effects of interseismic tectonic loading, static stress steps at the time of earthquakes, and postearthquake stress readjustment through viscoelastic...
Scaling the effects of moose browsing on forage distribution, from the geometry of plant canopies to landscapes
N. R. De Jager, J. Pastor, A.L. Hodgson
2009, Ecological Monographs (79) 281-297
Landscape heterogeneity influences large herbivores by altering their feeding rates, but as herbivores attempt to maximize feeding rates they also create spatial heterogeneity by altering plant growth. Herbivore feeding rates thus provide a quantitative link between the causes and consequences of spatial heterogeneity in herbivore-dominated ecosystems. The fractal geometry of...
On baseline corrections and uncertainty in response spectrafor baseline variations commonly encountered in digital accelerograph records
Sinan Akkar, David M. Boore
2009, Bulletin of the Seismological Society of America (99) 1671-1690
Most digital accelerograph recordings are plagued by long-period drifts, best seen in the velocity and displacement time series obtained from integration of the acceleration time series. These drifts often result in velocity values that are nonzero near the end of the record. This is clearly unphysical and can lead to...
Climatic extremes improve predictions of spatial patterns of tree species
N.E. Zimmermann, Nigel G. Yoccoz, T.C. Edwards Jr., E.S. Meier, W. Thuiller, Antoine Guisan, D.R. Schmatz, P.B. Pearman
2009, Conference Paper, Proceedings of the National Academy of Sciences of the United States of America
Understanding niche evolution, dynamics, and the response of species to climate change requires knowledge of the determinants of the environmental niche and species range limits. Mean values of climatic variables are often used in such analyses. In contrast, the increasing frequency of climate extremes suggests the importance of understanding their...
First-order exchange coefficient coupling for simulating surface water-groundwater interactions: Parameter sensitivity and consistency with a physics-based approach
B.A. Ebel, B.B. Mirus, C.S. Heppner, J.E. VanderKwaak, K. Loague
2009, Hydrological Processes (23) 1949-1959
Distributed hydrologic models capable of simulating fully-coupled surface water and groundwater flow are increasingly used to examine problems in the hydrologic sciences. Several techniques are currently available to couple the surface and subsurface; the two most frequently employed approaches are first-order exchange coefficients (a.k.a., the surface conductance method) and enforced...
Effects of rodent community diversity and composition on prevalence of an endemic bacterial pathogen - Bartonella
Y. Bai, M.Y. Kosoy, C.H. Calisher, J.F. Cully Jr., S.K. Collinge
2009, Biodiversity (10) 3-11
By studying Bartonella prevalence in rodent communities from 23 geographic sites in the western United States and one site in northern Mexico, the present study focused on the effects of rodent community diversity (measured by richness and Shannon index) and composition on prevalence of Bartonella infections. The analysis showed negative correlations of Bartonella prevalence with rodent...
Coastal ocean transport patterns in the central Southern California Bight
M.A. Noble, K.J. Rosenberger, P. Hamilton, J. P. Xu
2009, Special Paper of the Geological Society of America 193-226
In the past decade, several large programs that monitor currents and transport patterns for periods from a few months to a few years were conducted by a consortium of university, federal, state, and municipal agencies in the central Southern California Bight, a heavily urbanized section of the coastal ocean off...
Allogenic sedimentary components of Bear Lake, Utah and Idaho
J. G. Rosenbaum, W.E. Dean, R. L. Reynolds, M.C. Reheis
2009, Special Paper of the Geological Society of America 145-168
Bear Lake is a long-lived lake filling a tectonic depression between the Bear River Range to the west and the Bear River Plateau to the east, and straddling the border between Utah and Idaho. Mineralogy, elemental geochemistry, and magnetic properties provide information about variations in provenance of allogenic lithic material...
Persistence of effects of high sediment loading in a salmon-bearing river, northern California
Mary Ann Madej, V. Ozaki
2009, Special Paper of the Geological Society of America 43-55
Regional high-magnitude rainstorms have produced several large floods in north coastal California during the last century, which resulted in extensive massmovement activity and channel aggradation. Channel monitoring in Redwood Creek, through the use of cross-sectional surveys, thalweg profi les, and pebble counts, has documented the persistence and routing of channel-stored...
Using a coupled groundwater/surfacewater model to predict climate-change impacts to lakes in the Trout Lake watershed, Northern Wisconsin
John F. Walker, Randall J. Hunt, Steven L. Markstrom, Lauren E. Hay, John Doherty
2009, Conference Paper, Planning for an uncertain future - Monitoring, integration, and adaptation (SIR2009-5049)
A major focus of the U.S. Geological Survey’s Trout Lake Water, Energy, and Biogeochemical Budgets (WEBB) project is the development of a watershed model to allow predictions of hydrologic response to future conditions including land-use and climate change. The coupled groundwater/surface-water model GSFLOW was chosen for this purpose because it...
Interactions among wildland fires in a long-established Sierra Nevada natural fire area
B.M. Collins, J.D. Miller, A. E. Thode, M. Kelly, J. W. van Wagtendonk, S.L. Stephens
2009, Ecosystems (12) 114-128
We investigate interactions between successive naturally occurring fires, and assess to what extent the environments in which fires burn influence these interactions. Using mapped fire perimeters and satellite-based estimates of post-fire effects (referred to hereafter as fire severity) for 19 fires burning relatively freely over a 31-year period, we demonstrate...
Effect of species rarity on the accuracy of species distribution models for reptiles and amphibians in southern California
J. Franklin, K.E. Wejnert, S.A. Hathaway, C.J. Rochester, Robert N. Fisher
2009, Diversity and Distributions (15) 167-177
Aim: Several studies have found that more accurate predictive models of species' occurrences can be developed for rarer species; however, one recent study found the relationship between range size and model performance to be an artefact of sample prevalence, that is, the proportion of presence versus absence observations in the...
Do fish benefit from stream restoration in the Catskill Mountains?
Barry P. Baldigo, Anne G. Ernst
2009, Clear Waters (39) 54-59
Many streams across North America have been modified or restored in order to stabilize channel banks and beds; however, the effects of stream restoration on fish assemblages and stream habitat are seldom monitored, evaluated, or published. Because the impacts on ecosystems are poorly understood, subsequent restoration projects cannot build upon...
Fragmentary evidence of great-earthquake subsidence during holocene emergence, Valdivia estuary, South Central Chile
A.R. Nelson, K. Kashima, L. A. Bradley
2009, Bulletin of the Seismological Society of America (99) 71-86
A reconnaissance of Holocene stratigraphy beneath fringing marshes of the Valdivia estuary, where an M 9.5 earthquake caused 1-2 m of regional coseismic subsidence in 1960, shows only fragmentary evidence of prehistoric coseismic subsidence. In most of the 150 hand-driven cores that were examined, a distinct unconformity separates 0.5-1.5 m...
Selenium mass balance in the Great Salt Lake, Utah
X. Diaz, W.P. Johnson, D. L. Naftz
2009, Science of the Total Environment (407) 2333-2341
A mass balance for Se in the south arm of the Great Salt Lake was developed for September 2006 to August 2007 of monitoring for Se loads and removal flows. The combined removal flows (sedimentation and volatilization) totaled to a geometric mean value of 2079??kg Se/yr, with the estimated low...
Assessing the response of area burned to changing climate in western boreal North America using a Multivariate Adaptive Regression Splines (MARS) approach
M. S. Balshi, A. D. McGuire, P. Duffy, M. Flannigan, J. Walsh, J. Melillo
2009, Global Change Biology (15) 578-600
Fire is a common disturbance in the North American boreal forest that influences ecosystem structure and function. The temporal and spatial dynamics of fire are likely to be altered as climate continues to change. In this study, we ask the question: how will area burned in boreal North America by...
SSTL UK-DMC SLIM-6 data quality assessment
G. Chander, S. Saunier, M.J. Choate, P. L. Scaramuzza
2009, IEEE Transactions on Geoscience and Remote Sensing (47) 2380-2391
Satellite data from the Surrey Satellite Technology Limited (SSTL) United Kingdom (UK) Disaster Monitoring Constellation (DMC) were assessed for geometric and radiometric quality. The UK-DMC Surrey Linear Imager 6 (SLIM-6) sensor has a 32-m spatial resolution and a ground swath width of 640 km. The UK-DMC SLIM-6 design consists of...
Sensitivity analysis, calibration, and testing of a distributed hydrological model using error‐based weighting and one objective function
L. Foglia, Mary C. Hill, Steffen W. Mehl, P. Burlando
2009, Water Resources Research (45)
We evaluate the utility of three interrelated means of using data to calibrate the fully distributed rainfall‐runoff model TOPKAPI as applied to the Maggia Valley drainage area in Switzerland. The use of error‐based weighting of observation and prior information data, local sensitivity analysis, and single‐objective function nonlinear regression provides quantitative...
Environmental influences on speleothem growth in southwestern Oregon during the last 380, 000 years
Vasile Ersek, Steven W. Hostetler, Hai Cheng, Peter U. Clark, Faron S. Anslow, Alan C. Mix, R. Lawrence Edwards
2009, Earth and Planetary Science Letters (279) 316-325
The growth of carbonate formations in caves (speleothems) is sensitive to changes in environmental conditions at the surface (temperature, precipitation and vegetation) and can provide useful paleoclimatic and paleoenvironmental information. We use 73 230Th dates from speleothems collected from a cave in southwestern Oregon (USA) to constrain speleothem growth for...
