Soil nitrogen accretion along a floodplain terrace chronosequence in northwest Alaska: Influence of the nitrogen-fixing shrub Shepherdia canadensis
Charles Rhoades, Dan Binkley, Hlynur Oskarsson, Robert Stottlemyer
2008, Écoscience (15) 223-230
Nitrogen enters terrestrial ecosystems through multiple pathways during primary succession. We measured accumulation of total soil nitrogen and changes in inorganic nitrogen (N) pools across a 300-y sequence of river terraces in northwest Alaska and assessed the contribution of the nitrogen-fixing shrub Shepherdia canadensis. Our work compared 5 stages of floodplain...
On developing thermal cave detection techniques for earth, the moon and mars
J. Judson Wynne, Timothy N. Titus, Guillermo Chong Diaz
2008, Earth and Planetary Science Letters (272) 240-250
The purpose of this study is to (1) demonstrate the viability of detecting terrestrial caves at thermal-infrared wavelengths, (2) improve our understanding of terrestrial cave thermal behavior, (3) identify times of day when cave openings have the maximum thermal contrast with the surrounding surface regolith, and (4) further our understanding...
Stress changes from the 2008 Wenchuan earthquake and increased hazard in the Sichuan basin
T. Parsons, C. Ji, E. Kirby
2008, Nature (454) 509-510
On 12 May 2008, the devastating magnitude 7.9 (Wenchuan) earthquake struck the eastern edge of the Tibetan plateau, collapsing buildings and killing thousands in major cities aligned along the western Sichuan basin in China. After such a large-magnitude earthquake, rearrangement of stresses in the crust commonly leads to subsequent damaging...
Magnetic monitoring of earth and space
Jeffrey J. Love
2008, Physics Today (61) 31-37
For centuries, navigators of the world’s oceans have been familiar with an effect of Earth’s magnetic field: It imparts a directional preference to the needle of a compass. Although in some settings magnetic orientation remains important, the modern science of geomagnetismhas emerged from its romantic nautical origins and developed into a subject of great depth and...
Hydrated silicate minerals on Mars observed by the Mars Reconnaissance Orbiter CRISM instrument
J.F. Mustard, S.L. Murchie, S.M. Pelkey, B.L. Ehlmann, R.E. Milliken, J. A. Grant, J.-P. Bibring, F. Poulet, J. Bishop, E. N. Dobrea, L. Roach, F. Seelos, R. E. Arvidson, S. Wiseman, R. Green, C. Hash, D. Humm, E. Malaret, J.A. McGovern, K. Seelos, T. Clancy, R. Clark, D. des Marais, N. Izenberg, A. Knudson, Y. Langevin, T. Martin, P. McGuire, Robert Morris, M. Robinson, T. Roush, M. Smith, G. Swayze, H. Taylor, T. Titus, M. Wolff
2008, Nature (454) 305-309
Phyllosilicates, a class of hydrous mineral first definitively identified on Mars by the OMEGA (Observatoire pour la Mineralogie, L’Eau, les Glaces et l’Activitié) instrument1,<a id="ref-link-abstract-2" title="Poulet, F. et...
Cattail invasion of sedge/grass meadows in Lake Ontario: Photointerpretation analysis of sixteen wetlands over five decades
D.A. Wilcox, K.P. Kowalski, H.L. Hoare, M.L. Carlson, H.N. Morgan
2008, Journal of Great Lakes Research (34) 301-323
Photointerpretation studies were conducted to evaluate vegetation changes in wetlands of Lake Ontario and the upper St. Lawrence River associated with regulation of water levels since about 1960. The studies used photographs from 16 sites (four each from drowned river mouth, barrier beach, open embayment, and protected embayment wetlands) and...
Real-time PCR detection and quantification of nine potential sources of fecal contamination by analysis of mitochondrial Cytochrome b targets
W. B. Schill, M.V. Mathes
2008, Environmental Science & Technology (42) 5229-5234
We designed and tested real-time PCR probe/primer sets to detect and quantify Cytochrome b sequences of mitochondrial DNA (mtDNA) from nine vertebrate species of pet (dog), farm (cow, chicken, sheep, horse, pig), wildlife (Canada goose, white-tailed deer), and human. Linear ranges of the assays were from 101 to 108 copies/??l....
Aquatic insect ecophysiological traits reveal phylogenetically based differences in dissolved cadmium susceptibility
D.B. Buchwalter, D.J. Cain, C.A. Martin, Lingtian Xie, S. N. Luoma, T. Garland Jr.
2008, Proceedings of the National Academy of Sciences of the United States of America (105) 8321-8326
We used a phylogenetically based comparative approach to evaluate the potential for physiological studies to reveal patterns of diversity in traits related to susceptibility to an environmental stressor, the trace metal cadmium (Cd). Physiological traits related to Cd bioaccumulation, compartmentalization, and ultimately susceptibility were measured in 21 aquatic insect species...
The application of electrical conductivity as a tracer for hydrograph separation in urban catchments
B.A. Pellerin, W. M. Wollheim, X. Feng, C.J. Vororsmarty
2008, Hydrological Processes (22) 1810-1818
Two-component hydrograph separation was performed on 19 low-to-moderate intensity rainfall events in a 4.1-km2 urban watershed to infer the relative and absolute contribution of surface runoff (e.g. new water) to stormflow generation between 2001 and 2003. The electrical conductivity (EC) of water was used as a continuous and inexpensive tracer,...
Reactive flow models of the Anarraaq Zn-Pb-Ag deposit, Red Dog district, Alaska
C. Schardt, G. Garven, K.D. Kelley, D. L. Leach
2008, Mineralium Deposita (43) 735-757
The Red Dog ore deposit district in the Brooks Range of northern Alaska is host to several high-grade, shale-hosted Zn + Pb deposits. Due to the complex history and deformation of these ore deposits, the geological and hydrological conditions at the time of formation are poorly understood. Using geological observations...
Introduced mammalian predators induce behavioural changes in parental care in an endemic New Zealand bird
M. Massaro, A. Starling-Windhof, J.V. Briskie, T. E. Martin
2008, PLoS ONE (3)
The introduction of predatory mammals to oceanic islands has led to the extension of many birds. Although introduced predators should favour changes that reduce predation risk in surviving bird species, the ability of island birds to respond to such novel changes remains unstudied. We tested whether novel predation risk imposed...
Citronelle Dome: A giant opportunity for multizone carbon storage and enhanced oil recovery in the Mississippi Interior Salt Basin of Alabama
R.A. Esposito, J.C. Pashin, P.M. Walsh
2008, Environmental Geosciences (15) 53-62
The Citronelle Dome is a giant, salt-cored anticline in the eastern Mississippi Interior Salt Basin of southern Alabama that is located near several large-scale, stationary, carbon-emitting sources in the greater Mobile area. The dome forms an elliptical, four-way structural closure containing opportunities for CO2-enhanced oil recovery (CO2-EOR) and large-capacity saline...
Compositional stratigraphy of clay-bearing layered deposits at Mawrth Vallis, Mars
J.J. Wray, B.L. Ehlmann, S. W. Squyres, J.F. Mustard, Randolph L. Kirk
2008, Geophysical Research Letters (35)
Phyllosilicates have previously been detected in layered outcrops in and around the Martian outflow channel Mawrth Vallis. CRISM spectra of these outcrops exhibit features diagnostic of kaolinite, montmorillonite, and Fe/Mg-rich smectites, along with crystalline ferric oxide minerals such as hematite. These minerals occur in distinct stratigraphic horizons, implying changing environmental...
Movement patterns and study area boundaries: Influences on survival estimation in capture-mark-recapture studies
G.E. Horton, B. H. Letcher
2008, Oikos (117) 1131-1142
The inability to account for the availability of individuals in the study area during capture-mark-recapture (CMR) studies and the resultant confounding of parameter estimates can make correct interpretation of CMR model parameter estimates difficult. Although important advances based on the Cormack-Jolly-Seber (CJS) model have resulted in estimators of true survival...
Size and age distributions of Juvenile Connecticut River American shad above Hadley Falls: Influence on outmigration representation and timing
M. J. O'Donnell, B. H. Letcher
2008, River Research and Applications (24) 929-940
Age- and size-based habitat use and movement patterns of young-of-year American shad in rivers are not well understood. Adult females reach their natal rivers at different times and ascend the river at different rates, which may lead to variation of hatch dates at a single location. Also, shad are serial...
Species composition and habitat associations of benthic algal assemblages in headwater streams of the Sierra Nevada, California
L. R. Brown, J. T. May, C.T. Hunsaker
2008, Western North American Naturalist (68) 194-209
Despite their trophic importance and potential importance as bioindicators of stream condition, benthic algae have not been well studied in California. In particular there are few studies from small streams in the Sierra Nevada. The objective of this study was to determine the standing crop of chlorophyll-a and benthic algal...
Using bioenergetics modeling to estimate consumption of native juvenile salmonids by nonnative northern pike in the Upper Flathead River System, Montana
C.C. Muhlfeld, D.H. Bennett, Steinhorst R. Kirk, B. Marotz, M. Boyer
2008, North American Journal of Fisheries Management (28) 636-648
Introductions of nonnative northern pike Esox lucius have created recreational fisheries in many waters in the United States and Canada, yet many studies have shown that introduced northern pike may alter the composition and structure of fish communities through predation. We estimated the abundance of nonnative northern pike (2002-2003) and...
Satellite-derived aerosol radiative forcing from the 2004 British Columbia wildfires
Song Guo, H. Leighton
2008, Atmosphere - Ocean (46) 203-212
The British Columbia wildfires of 2004 was one of the largest wildfire events in the last ten years in Canada. Both the shortwave and longwave smoke aerosol radiative forcing at the top-of-atmosphere (TOA) are investigated using data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Clouds and the Earth's...
Population size and relative abundance of adult Alabama shad reaching jim woodruff lock and dam, Apalachicola River, Florida
Patrick C. Ely, S.P. Young, J. Jeffery Isely
2008, North American Journal of Fisheries Management (28) 827-831
We estimated the population size of migrating Alabama shad Alosa alabamae below Jim Woodruff Lock and Dam in the Apalachicola River (located in the central panhandle of northwestern Florida) using mark-recapture and relative abundance techniques. After adjustment for tag loss, emigration, and mortality, the population size was estimated as 25,935...
Contaminant levels in rainbow trout, Oncorhynchus mykiss, and their diets from Missouri coldwater hatcheries
M.J. McKee, G.B. Kromrey, T.W. May, C.E. Orazio
2008, Bulletin of Environmental Contamination and Toxicology (80) 450-454
Organochlorine and metal contaminants often occur in commercial fish diets and can accumulate in fish to levels of concern for human consumption. Contaminant levels were investigated in diet and rainbow trout fillets from Missouri coldwater hatcheries used in 'put and take' fisheries. The average fillet:diet ratio was <0.1 for lead...
Landslide hazard mitigation in North America
G. F. Wieczorek, P.P. Leahy
2008, Environmental & Engineering Geoscience (14) 133-144
Active landslides throughout the states and territories of the United States result in extensive property loss and 25-50 deaths per year. The U.S. Geological Survey (USGS) has a long history of detailed examination of landslides since the work of Howe (1909) in the San Juan Mountains of Colorado. In the...
Method for estimating spatially variable seepage loss and hydraulic conductivity in intermittent and ephemeral streams
R.G. Niswonger, David E. Prudic, G.E. Fogg, David A. Stonestrom, E.M. Buckland
2008, Water Resources Research (44)
A method is presented for estimating seepage loss and streambed hydraulic conductivity along intermittent and ephemeral streams using streamflow front velocities in initially dry channels. The method uses the kinematic wave equation for routing streamflow in channels coupled to Philip's equation for infiltration. The coupled model considers variations in seepage...
Distribution of glacial deposits, soils, and permafrost in Taylor Valley, Antarctica
James G. Bockheim, M.L. Prentice, M. McLeod
2008, Arctic, Antarctic, and Alpine Research (40) 279-286
We provide a map of lower and central Taylor Valley, Antarctica, that shows deposits from Taylor Glacier, local alpine glaciers, and grounded ice in the Ross Embayment. From our electronic database, which includes 153 sites from the coast 50 km upvalley to Pearse Valley, we show the distribution of permafrost...
Hydrocarbon lakes on Titan: Distribution and interaction with a porous regolith
A. Hayes, O. Aharonson, P. Callahan, C. Elachi, Y. Gim, Randolph L. Kirk, K. Lewis, R. Lopes, R. Lorenz, J. Lunine, Ken Mitchell, Giuseppe Mitri, E. Stofan, S. Wall
2008, Geophysical Research Letters (35)
Synthetic Aperture Radar (SAR) images of Titan's north polar region reveal quasi‐circular to complex features which are interpreted to be liquid hydrocarbon lakes. We investigate methane transport in Titan's hydrologic cycle using the global distribution of lake features. As of May 2007, the SAR data set covers ∼22% of the...
Evaluating the effects of historical land cover change on summertime weather and climate in New Jersey: Land cover and surface energy budget changes
P. S. Wichansky, L. T. Steyaert, R. L. Walko, C. P. Waever
2008, Journal of Geophysical Research-Atmospheres (113)
The 19th-century agrarian landscape of New Jersey (NJ) and the surrounding region has been extensively transformed to the present-day land cover by urbanization, reforestation, and localized areas of deforestation. This study used a mesoscale atmospheric numerical model to investigate the sensitivity of the warm season climate of NJ to these...
