Multibeam observations of mine burial near Clearwater, FL, including comparisons to predictions of wave-induced burial
M.L. Wolfson, D. F. Naar, P.A. Howd, S. D. Locker, B.T. Donahue, Carl T. Friedrichs, A.C. Trembanis, M. D. Richardson, T.F. Wever
2007, IEEE Journal of Oceanic Engineering (32) 103-118
A Kongsberg Simrad EM 3000 multibeam sonar (Kongsberg Simrad, Kongsberg, Norway) was used to conduct a set of six repeat high-resolution bathymetric surveys west of Indian Rocks Beach (IRB), just to the south of Clearwater, FL, between January and March 2003, to observe in situ scour and burial of instrumented...
Using multiple gears to assess acoustic detectability and biomass of fish species in lake superior
D.L. Yule, J.V. Adams, J.D. Stockwell, O. T. Gorman
2007, North American Journal of Fisheries Management (27) 106-126
Recent predator demand and prey supply studies suggest that an annual daytime bottom trawl survey of Lake Superior underestimates prey fish biomass. A multiple-gear (acoustics, bottom trawl, and midwater trawl) nighttime survey has been recommended, but before abandoning a long-term daytime survey the effectiveness of night sampling of important prey...
Electrofishing capture probability of smallmouth bass in streams
D.C. Dauwalter, W.L. Fisher
2007, North American Journal of Fisheries Management (27) 162-171
Abundance estimation is an integral part of understanding the ecology and advancing the management of fish populations and communities. Mark-recapture and removal methods are commonly used to estimate the abundance of stream fishes. Alternatively, abundance can be estimated by dividing the number of individuals sampled by the probability of capture....
First report of Jefferson's ground sloth (Megalonyx jeffersonii) in North Dakota: Paleobiogeographical and paleoecological significance
J.W. Hoganson, H. Gregory McDonald
2007, Journal of Mammalogy (88) 73-80
A well-preserved ungual of a pes documents the presence of Jefferson's ground sloth (Megalonyx jeffersonii) at the end of the Wisconsinan in North Dakota. This is the 1st report of M. jeffersonii in North Dakota, and one of few records from the upper Great Plains. An accelerator mass spectrometer radiocarbon...
A field investigation of phreatophyte‐induced fluctuations in the water table
James J. Butler Jr., Gerard J. Kluitenberg, Donald O. Whittemore, Steven P. Loheide II, Wei Jin, Mark A. Billinger, Xiaoyong Zhan
2007, Water Resources Research (43)
Hydrographs from shallow wells in vegetated riparian zones frequently display a distinctive pattern of diurnal water table fluctuations produced by variations in plant water use. A multisite investigation assessed the major controls on these fluctuations and the ecohydrologic insights that can be gleaned from them. Spatial and temporal variations in...
Solar forcing of Gulf of California climate during the past 2000 yr suggested by diatoms and silicoflagellates
John A. Barron, David Bukry
2007, Marine Micropaleontology (62) 115-139
High-resolution records of the past 2000 yr are compared in a north–south transect (28° N to 24° N) of three cores from the eastern slopes of the Guaymas, Carmen, and Pescadero Basins of the Gulf of California (hereafter referred to as the “Gulf”). Evenly-spaced samples from the varved sediments in each...
The lakes of Titan
Ellen R. Stofan, Charles Elachi, Jonathan I. Lunine, Ralf D. Lorenz, B. Stiles, K. L. Mitchell, S. Ostro, Laurence A. Soderblom, C. Wood, H. Zebker, S. Wall, Michael A. Janssen, Randolph L. Kirk, Rosaly Lopes, F. Paganelli, Jani Radebaugh, L. Wye, Y. Anderson, M. Allison, R. Boehmer, P. Callahan, P. Encrenaz, E. Flamini, G. Francescetti, Y. Gim, G. Hamilton, S. Hensley, W.T.K. Johnson, K. Kelleher, D. Muhleman, Philipe Paillou, G. Picardi, F. Posa, L. Roth, R. Seu, S. Shaffer, S. Vetrella, R. West
2007, Nature (445) 61-64
The surface of Saturn’s haze-shrouded moon Titan has long been proposed to have oceans or lakes, on the basis of the stability of liquid methane at the surface1,2. Initial visible3 and radar4,5 imaging failed to find any evidence of an ocean, although abundant evidence was found that flowing liquids have existed on...
Seismoelectric imaging of shallow targets
S.S. Haines, S.R. Pride, S.L. Klemperer, B. Biondi
2007, Geophysics (72)
We have undertaken a series of controlled field experiments to develop seismoelectric experimental methods for near-surface applications and to improve our understanding of seismoelectric phenomena. In a set of off-line geometry surveys (source separated from the receiver line), we place seismic sources and electrode array receivers on opposite sides of...
Spatial correlation of shear-wave velocity in the San Francisco Bay Area sediments
E.M. Thompson, L.G. Baise, R. E. Kayen
2007, Soil Dynamics and Earthquake Engineering (27) 144-152
Ground motions recorded within sedimentary basins are variable over short distances. One important cause of the variability is that local soil properties are variable at all scales. Regional hazard maps developed for predicting site effects are generally derived from maps of surficial...
Evapotranspiration in a cottonwood (Populus fremontii) restoration plantation estimated by sap flow and remote sensing methods
P. Nagler, A. Jetton, J. Fleming, K. Didan, E. Glenn, J. Erker, K. Morino, J. Milliken, S. Gloss
2007, Agricultural and Forest Meteorology (144) 95-110
Native tree plantations have been proposed for the restoration of wildlife habitat in human-altered riparian corridors of western U.S. rivers. Evapotranspiration (ET) by riparian vegetation is an important, but poorly quantified, term in river water budgets. Native tree restoration plots will potentially increase ET. We used sap flow sensors and...
North to Alaska: Evidence for conveyor belt transport of Dungeness crab larvae along the west coast of the United States and Canada
W. Park, David C. Douglas, Thomas C. Shirley
2007, Limnology and Oceanography (52) 248-256
We propose and evaluate the hypothesis that Dungeness crab (Cancer magister) larvae from the northwestern coast of the United States and Canada can be transported northward to southeastern Alaska. Larvae collected in southeastern Alaska during May and June 1997–2004 had abundances and stages that varied seasonally, interannually, and spatially. An...
SHRIMP U-Pb evidence for a Late Silurian age of metasedimentary rocks in the Merrimack and Putnam-Nashoba terranes, eastern New England
R. P. Wintsch, J. N. Aleinikoff, G. J. Walsh, Wallace A. Bothner, A. M. Hussey, C.M. Fanning
2007, American Journal of Science (307) 119-167
U-Pb ages of detrital, metamorphic, and magmatic zircon and metamorphic monazite and titanite provide evidence for the ages of deposition and metamorphism of metasedimentary rocks from the Merrimack and Putnam-Nashoba terranes of eastern New England. Rocks from these terranes are interpreted here as having been deposited in the middle Paleozoic...
Fish assemblages of the upper Little Sioux River basin, Iowa, USA: Relationships with stream size and comparison with historical assemblages
D. Palic, L. Helland, B.R. Pedersen, J.R. Pribil, R.M. Grajeda, Anna Loan-Wilsey, C.L. Pierce
2007, Journal of Freshwater Ecology (22) 69-79
We characterized the fish assemblages in second to fifth order streams of the upper Little Sioux River basin in northwest Iowa, USA and compared our results with historical surveys. The fish assemblage consisted of over twenty species, was dominated numerically by creek chub, sand shiner, central stoneroller and other cyprinids,...
Global impacts of conversions from natural to agricultural ecosystems on water resources: Quantity versus quality
Bridget R. Scanlon, Ian Jolly, Marios Sophocleous, Lu Zhang
2007, Water Resources Research (43)
Past land use changes have greatly impacted global water resources, with often opposing effects on water quantity and quality. Increases in rain‐fed cropland (460%) and pastureland (560%) during the past 300 years from forest and grasslands decreased evapotranspiration and increased recharge (two orders of magnitude) and streamflow (one order of...
Conversations on the habitability of worlds: The importance of volatiles
J.-L. Bertaux, M. Carr, D.J. Des Marais, E. Gaidos
2007, Space Science Reviews (129) 123-165
Our scientific forefathers discuss the interrelationships between water, climate, the atmosphere, and life on Earth and other terrestrial planets at a workshop in Nichtcha??tel, Switzerland. ?? 2007 Springer Science+Business Media B.V....
Sinter-vein correlations at Buckskin Mountain, National district, Humboldt County, Nevada
P.G. Vikre
2007, Economic Geology (102) 193-224
At Buckskin Mountain (elev 2,650 m, 8,743 ft), Humboldt County, Nevada, a hydrothermal system, imposed on a middle Miocene volcanic sequence with contrasting permeabilities and tensile strengths, produced alteration assemblages controlled by elevation, from Hg-mineralized sinter to subjacent precious metal veins over a vertical distance exceeding 790 m. Sinter and...
A comparison of four geophysical methods for determining the shear wave velocity of soils
N. Anderson, T. Thitimakorn, A. Ismail, D. Hoffman
2007, Environmental & Engineering Geoscience (13) 11-23
The Missouri Department of Transportation (MoDOT) routinely acquires seismic cone penetrometer (SCPT) shear wave velocity control as part of the routine investigation of soils within the Mississippi Embayment. In an effort to ensure their geotechnical investigations are as effective and efficient as possible, the SCPT tool and several available alternatives...
Quantifying fluid and bed dynamics for characterizing benthic physical habitat in large rivers
D. Gaeuman, R. B. Jacobson
2007, Journal of Applied Ichthyology (23) 359-364
Sturgeon use benthic habitats in and adjacent to main channels where environmental conditions can include bedload sediment transport and high near-bed flow velocities. Bed velocity measurements obtained with acoustic Doppler instruments provide a means to assess the concentration and velocity of sediment moving near the streambed, and are thus indicative...
Shorebird abundance and distribution on the coastal plain of the Arctic National Wildlife Refuge
S. Brown, J. Bart, Richard B. Lanctot, J. A. Johnson, S. Kendall, D. Payer, J. Johnson
2007, Condor (109) 1-14
The coastal plain of the Arctic National Wildlife Refuge hosts seven species of migratory shorebirds listed as highly imperiled or high priority by the U.S. Shorebird Conservation Plan and five species listed as Birds of Conservation Concern by the U.S. Fish and Wildlife Service. During the first comprehensive shorebird survey...
Vertical spatial sensitivity and exploration depth of low-induction-number electromagnetic-induction instruments
J.B. Callegary, T.P.A. Ferre, R.W. Groom
2007, Vadose Zone Journal (6) 158-167
Vertical spatial sensitivity and effective depth of exploration (d e) of low-induction-number (LIN) instruments over a layered soil were evaluated using a complete numerical solution to Maxwell's equations. Previous studies using approximate mathematical solutions predicted a vertical spatial sensitivity for instruments operating under LIN conditions that, for a given transmitter-receiver...
Chinook salmon use of spawning patches: Relative roles of habitat quality, size, and connectivity
D.J. Isaak, R.F. Thurow, B.E. Rieman, J. B. Dunham
2007, Ecological Applications (17) 352-364
Declines in many native fish populations have led to reassessments of management goals and shifted priorities from consumptive uses to species preservation. As management has shifted, relevant environmental characteristics have evolved from traditional metrics that described local habitat quality to characterizations of habitat size and connectivity. Despite the implications this...
Associations of decadal to multidecadal sea-surface temperature variability with Upper Colorado River flow
G.J. McCabe, J.L. Betancourt, H.G. Hidalgo
2007, Journal of the American Water Resources Association (43) 183-192
The relations of decadal to multidecadal (D2M) variability in global sea-surface temperatures (SSTs) with D2M variability in the flow of the Upper Colorado River Basin (UCRB) are examined for the years 1906-2003. Results indicate that D2M variability of SSTs in the North Atlantic, North Pacific, tropical Pacific, and Indian Oceans...
Late nineteenth to early twenty-first century behavior of Alaskan glaciers as indicators of changing regional climate
B. F. Molnia
2007, Global and Planetary Change (56) 23-56
Alaska's climate is changing and one of the most significant indications of this change has been the late 19th to early 21st century behavior of Alaskan glaciers. Weather station temperature data document that air temperatures throughout Alaska have been increasing for many decades. Since the mid-20th century, the average change...
Resource availability, matrix quality, microclimate, and spatial pattern as predictors of patch use by the Karner blue butterfly
R. Grundel, N.B. Pavlovic
2007, Biological Conservation (135) 135-144
Determination of which aspects of habitat quality and habitat spatial arrangement best account for variation in a species’ distribution can guide management for organisms such as the Karner blue butterfly (Lycaeides melissa samuelis), a federally endangered subspecies inhabiting savannas of Midwest and Eastern United States. We examined the extent to...
Use of streamflow data to estimate base flowground-water recharge for Wisconsin
W.A. Gebert, M.J. Radloff, E.J. Considine, J.L. Kennedy
2007, Journal of the American Water Resources Association (43) 220-236
The average annual base flow/recharge was determined for streamflow-gaging stations throughout Wisconsin by base-flow separation. A map of the State was prepared that shows the average annual base flow for the period 1970-99 for watersheds at 118 gaging stations. Trend analysis was performed on 22 of the 118 streamflow-gaging stations...
