Effects of water additions, chemical amendments, and plants on in situ measures of nutrient bioavailability in calcareous soils of southeastern Utah, USA
M. E. Miller, J. Belnap, S.W. Beatty, B.L. Webb
2006, Plant and Soil (288) 19-29
We used ion-exchange resin bags to investigate effects of water additions, chemical amendments, and plant presence on in situ measures of nutrient bioavailability in conjunction with a study examining soil controls of ecosystem invasion by the exotic annual grass Bromus tectorum L. At five dryland sites in southeastern Utah, USA,...
Comet 81P/wild 2 under a microscope
D. Brownlee, P. Tsou, J. Aleon, Alexander C. M. O’D C. M., T. Araki, S. Bajt, G.A. Baratta, R. Bastien, P. Bland, P. Bleuet, J. Borg, J.P. Bradley, A. Brearley, F. Brenker, S. Brennan, J.C. Bridges, N.D. Browning, J.R. Brucato, E. Bullock, M.J. Burchell, H. Busemann, Anna L. Butterworth, M. Chaussidon, A. Cheuvront, M. Chi, M.J. Cintala, B. C. Clark, S.J. Clemett, G. Cody, L. Colangeli, G. Cooper, P. Cordier, C. Daghlian, Z. Dai, L. D’Hendecourt, Z. Djouadi, G. Dominguez, T. Duxbury, J.P. Dworkin, D.S. Ebel, T.E. Economou, S. Fakra, S.A.J. Fairey, S. Fallon, G. Ferrini, T. Ferroir, H. Fleckenstein, C. Floss, G. Flynn, I.A. Franchi, M. Fries, Z. Gainsforth, J.-P. Gallien, M. Genge, M.K. Gilles, P. Gillet, J. Gilmour, D.P. Glavin, M. Gounelle, Monica M. Grady, G.A. Graham, P.G. Grant, S.F. Green, F. Grossemy, L. Grossman, J. N. Grossman, Y. Guan, K. Hagiya, R. Harvey, P. Heck, G.F. Herzog, P. Hoppe, F. Horz, J. Huth, I.D. Hutcheon, K. Ignatyev, H. Ishii, M. Ito, D. Jacob, C. Jacobsen, S. Jacobsen, S. Jones, D. Joswiak, A. Jurewicz, A.T. Kearsley, L.P. Keller, H. Khodja, A.L.D. Kilcoyne, J. Kissel, A. Krot, F. Langenhorst, A. Lanzirotti, L. Le, L.A. Leshin, J. Leitner, L. Lemelle, H. Leroux, M.-C. Liu, K. Luening, I. Lyon, G. MacPherson, M.A. Marcus, K. Marhas, B. Marty, G. Matrajt, K. McKeegan, A. Meibom, V. Mennella, K. Messenger, S. Messenger, T. Mikouchi, S. Mostefaoui, T. Nakamura, T. Nakano, M. Newville, L.R. Nittler, I. Ohnishi, K. Ohsumi, K. Okudaira, D.A. Papanastassiou, R. Palma, M.E. Palumbo, R. O. Pepin, D. Perkins, M. Perronnet, P. Pianetta, W. Rao, F.J.M. Rietmeijer, F. Robert, D. Rost, A. Rotundi, R. Ryan, S.A. Sandford, C.S. Schwandt, T.H. See, D. Schlutter, J. Sheffield-Parker, A. Simionovici, S. Simon, I. Sitnitsky, C.J. Snead, M. K. Spencer, F.J. Stadermann, A. Steele, T. Stephan
2006, Science (314) 1711-1716
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains...
Quantitative analysis of scale of aeromagnetic data raises questions about geologic-map scale
V. Nykanen, G. L. Raines
2006, Natural Resources Research (15) 213-222
A recently published study has shown that small-scale geologic map data can reproduce mineral assessments made with considerably larger scale data. This result contradicts conventional wisdom about the importance of scale in mineral exploration, at least for regional studies. In order to formally investigate aspects of scale, a weights-of-evidence analysis...
Do migratory flight paths of raptors follow constant geographical or geomagnetic courses?
K. Thorup, M. Fuller, T. Alerstam, M. Hake, N. Kjellen, R. Strandberg
2006, Animal Behaviour (72) 875-880
We tested whether routes of raptors migrating over areas with homogeneous topography follow constant geomagnetic courses more or less closely than constant geographical courses. We analysed the routes taken over land of 45 individual raptors tracked by satellite-based radiotelemetry: 25 peregrine falcons, Falco peregrinus, on autumn migration between North and...
Sampling blood from big brown bats (Eptesicus fuscus) in the field with and without anesthesia: Impacts on survival
L.E. Ellison, T. J. O'Shea, J. Wimsatt, R.D. Pearce, D.J. Neubaum, M.A. Neubaum, R. A. Bowen
2006, Journal of Wildlife Diseases (42) 849-852
Blood was collected from wild big brown bats (Eptesicus fuscus) with and without anesthesia in Fort Collins, Colorado in 2004 to assess the impacts of these procedures on short-term survival and 1-yr return rates. Short-term survival and 1-yr return rates after release were passively monitored using PIT tag detection hoops...
Spatial and temporal patterns of wildfires in the Mojave Desert, 1980-2004
M.L. Brooks, J.R. Matchett
2006, Journal of Arid Environments (67) 148-164
Fire has been historically infrequent in the Mojave Desert, and its increased prevalence caused by the invasion of non-native annual grasses is a major concern for land managers there. The most dramatic changes have occurred in middle elevation shrublands dominated by creosotebush (Larrea tridentata), Joshua tree (Yucca brevifolia), and/or blackbrush...
Survival of adult female elk in yellowstone following wolf restoration
S.B. Evans, L.D. Mech, P.J. White, G.A. Sargeant
2006, Journal of Wildlife Management (70) 1372-1378
Counts of northern Yellowstone elk (Cervus elaphus) in northwestern Wyoming and adjacent Montana, USA, have decreased at an average rate of 6-8% per year since wolves (Canis lupus) were reintroduced in 1995. Population growth rates of elk are typically sensitive to variations in adult female survival; populations that are stable...
Differences between near-surface equivalent temperature and temperature trends for the Eastern United States. Equivalent temperature as an alternative measure of heat content
C.A. Davey, R.A. Pielke Sr., K. P. Gallo
2006, Global and Planetary Change (54) 19-32
There is currently much attention being given to the observed increase in near-surface air temperatures during the last century. The proper investigation of heating trends, however, requires that we include surface heat content to monitor this aspect of the climate system. Changes in heat content of the Earth's climate are...
Hyporheic exchange and fulvic acid redox reactions in an alpine stream/wetland ecosystem, Colorado front range
Matthew P. Miller, Diane M. McKnight, R.M. Cory, Mark W. Williams, Robert L. Runkel
2006, Environmental Science & Technology (40) 5943-5949
The influence of hyporheic zone interactions on the redox state of fulvic acids and other redox active species was investigated in an alpine stream and adjacent wetland, which is a more reducing environment. A tracer injection experiment using bromide (Br-) was conducted in the stream system. Simulations...
Giant sand waves at the mouth of San Francisco Bay
P.L. Barnard, D.M. Hanes, D. M. Rubin, R.G. Kvitek
2006, Eos, Transactions, American Geophysical Union (87) 287-289
A field of giant sand waves, among the largest in the world, recently was mapped in high resolution for the first time during a multibeam survey in 2004 and 2005 through the strait of the Golden Gate at the mouth of San Francisco Bay in California (Figure la). This massive...
Mineralogy and petrology of comet 81P/wild 2 nucleus samples
M.E. Zolensky, T.J. Zega, H. Yano, S. Wirick, A.J. Westphal, M.K. Weisberg, I. Weber, J.L. Warren, M.A. Velbel, A. Tsuchiyama, P. Tsou, A. Toppani, N. Tomioka, K. Tomeoka, N. Teslich, M. Taheri, J. Susini, R. Stroud, T. Stephan, F.J. Stadermann, C.J. Snead, S.B. Simon, A. Simionovici, T.H. See, F. Robert, F.J.M. Rietmeijer, W. Rao, M.C. Perronnet, D.A. Papanastassiou, K. Okudaira, K. Ohsumi, I. Ohnishi, K. Nakamura-Messenger, T. Nakamura, S. Mostefaoui, T. Mikouchi, A. Meibom, G. Matrajt, M.A. Marcus, H. Leroux, L. Lemelle, L. Le, A. Lanzirotti, F. Langenhorst, A.N. Krot, L.P. Keller, A.T. Kearsley, D. Joswiak, D. Jacob, H. Ishii, R. Harvey, K. Hagiya, L. Grossman, J.H. Grossman, G.A. Graham, M. Gounalle, P. Gillet, M.J. Genge, G. Flynn, T. Ferroir, S. Fallon, D.S. Ebel, Z.R. Dai, P. Cordier, B. Clark, M. Chi, Anna L. Butterworth, D.E. Brownlee, J.C. Bridges, S. Brennan, A. Brearley, J.P. Bradley, P. Bleuet, P.A. Bland, R. Bastien
2006, Science (314) 1735-1739
The bulk of the comet 81P/Wild 2 (hereafter Wild 2) samples returned to Earth by the Stardust spacecraft appear to be weakly constructed mixtures of nanometer-scale grains, with occasional much larger (over 1 micrometer) ferromagnesian silicates, Fe-Ni sulfides, Fe-Ni metal, and accessory phases. The very wide range of olivine and...
Ripple effect: Unforeseen applications of sand studies
D. M. Rubin
2006, Eos, Transactions, American Geophysical Union (87) 295-296
[No abstract available]...
Complementary population dynamics of exotic and native Daphnia in North American reservoir communities
J.E. Havel, J.L. Graham
2006, Archiv fur Hydrobiologie (167) 245-264
During its invasion of North America, the exotic Daphnia lumholtzi has rapidly colonized numerous reservoirs, natural lakes, and large rivers. In the current study, we examine the overlap between D. lumholtzi and native Daphnia species through analysis of two data sets: co-occurrence in reservoirs of the south-central United States and...
Use of cotton gin trash to enhance denitrification in restored forested wetlands
S. Ullah, S.P. Faulkner
2006, Forest Ecology and Management (237) 557-563
Lower Mississippi Valley (LMV) has lost about 80% bottomland hardwood forests, mainly to agriculture. This landscape scale alteration of the LMV resulted in the loss of nitrate (NO3) removal capacity of the valley, contributing to nitrogen (N)-enhanced eutrophication and potentially hypoxia in the northern Gulf of Mexico. Restoration of hardwood...
Fine-scale population genetic structure of a wildlife disease vector: The southern house mosquito on the island of Hawaii
N. Keyghobadi, D. LaPointe, R.C. Fleischer, D.M. Fonseca
2006, Molecular Ecology (15) 3919-3930
The southern house mosquito, Culex quinquefasciatus, is a widespread tropical and subtropical disease vector. In the Hawaiian Islands, where it was introduced accidentally almost two centuries ago, it is considered the primary vector of avian malaria and pox. Avian malaria in particular has contributed to the extinction and endangerment of...
Net energy payback and CO2 emissions from three midwestern wind farms: An update
S.W. White
2006, Natural Resources Research (15) 271-281
This paper updates a life-cycle net energy analysis and carbon dioxide emissions analysis of three Midwestern utility-scale wind systems. Both the Energy Payback Ratio (EPR) and CO2 analysis results provide useful data for policy discussions regarding an efficient and low-carbon energy mix. The EPR is the amount of electrical energy...
Testing the junk-food hypothesis on marine birds: Effects of prey type on growth and development
Marc D. Romano, John F. Piatt, D.D. Roby
2006, Waterbirds (29) 407-414
The junk-food hypothesis attributes declines in productivity of marine birds and mammals to changes in the species of prey they consume and corresponding differences in nutritional quality of those prey. To test this hypothesis nestling Black-legged Kittiwakes (Rissa tridactyla) and Tufted Puffins (Fratercula cirrhata) were raised in captivity under controlled...
Old-growth forests can accumulate carbon in soils
G. Zhou, S. Liu, Z. Li, Dongxiao Zhang, X. Tang, C. Zhou, J. Yan, J. Mo
2006, Science (314) 1417-1417
Old-growth forests have traditionally been considered negligible as carbon sinks because carbon uptake has been thought to be balanced by respiration. We show that the top 20-centimeter soil layer in preserved old-growth forests in southern China accumulated atmospheric carbon at...
Controls on soil pore water solutes: An approach for distinguishing between biogenic and lithogenic processes
A. F. White, M. S. Schulz, D.V. Vivit, A.E. Blum, David A. Stonestrom
2006, Journal of Geochemical Exploration (88) 363-366
Spatial and temporal variations in pore water compositions are characterized for a deep regolith profile developed on a marine terrace chronosequence near Santa Cruz California. Variations are resolved in terms of the dominance of either a lithogenic process, i.e. chemical weathering, or a biogenic process, i.e. plant nutrient cycling. The concept of elemental fractionation is introduced describing...
Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA
C.R. Fenton, R. H. Webb, T.E. Cerling
2006, Quaternary Research (65) 324-335
The failure of a lava dam 165,000 yr ago produced the largest known flood on the Colorado River in Grand Canyon. The Hyaloclastite Dam was up to 366 m high, and geochemical evidence linked this structure to outburst-flood deposits that occurred for 32 km downstream. Using the Hyaloclastite outburst-flood deposits...
Ecological values of shallow-water habitats: Implications for the restoration of disturbed ecosystems
C.B. Lopez, J. E. Cloern, T.S. Schraga, A.J. Little, L.V. Lucas, J.K. Thompson, J.R. Burau
2006, Ecosystems (9) 422-440
A presumed value of shallow-habitat enhanced pelagic productivity derives from the principle that in nutrient-rich aquatic systems phytoplankton growth rate is controlled by light availability, which varies inversely with habitat depth. We measured a set of biological indicators across the gradient of habitat depth within the Sacramento–San Joaquin River...
Geologic, hydrologic, and geochemical interpretations of mineral deposits as analogs for understanding transport of environmental contaminants
R. B. Wanty, B. R. Berger
2006, Journal of Geochemical Exploration (88) 162-165
Base- and precious-metal mineral deposits comprise anomalous concentrations of metals and associated elements, which may be useful subjects for study as analogs for migration of environmental contaminants. In the geologic past, hydrothermal mineral deposits formed at the intersection of favorable geologic, hydrologic and geochemical gradients. In the present, weathering of...
The quest for the perfect gravity anomaly: Part 2 - Mass effects and anomaly inversion
Gordon R. Keller, T.G. Hildenbrand, W. J. Hinze, X. Li, D. Ravat, M. Webring
2006, SEG Technical Program Expanded Abstracts (25) 864-868
Gravity anomalies have become an important tool for geologic studies since the widespread use of high-precision gravimeters after the Second World War. More recently the development of instrumentation for airborne gravity observations, procedures for acquiring data from satellite platforms, the readily available Global Positioning System for precise vertical and horizontal...
Predicted liquefaction of East Bay fills during a repeat of the 1906 San Francisco earthquake
T.L. Holzer, J.L. Blair, T.E. Noce, M.J. Bennett
2006, Earthquake Spectra (22)
Predicted conditional probabilities of surface manifestations of liquefaction during a repeat of the 1906 San Francisco (M7.8) earthquake range from 0.54 to 0.79 in the area underlain by the sandy artificial fills along the eastern shore of San Francisco Bay near Oakland, California. Despite widespread liquefaction in 1906 of sandy...
Spectral variability among rocks in visible and near-infrared mustispectral Pancam data collected at Gusev crater: Examinations using spectral mixture analysis and related techniques
W. H. Farrand, J.F. Bell, J. R. Johnson, S. W. Squyres, J. Soderblom, D. W. Ming
2006, Journal of Geophysical Research E: Planets (111)
Visible and near-infrared (VNIR) multispectral observations of rocks made by the Mars Exploration Rover Spirit's Panoramic camera (Pancam) have been analyzed using a spectral mixture analysis (SMA) methodology. Scenes have been examined from the Gusev crater plains into the Columbia Hills. Most scenes on the plains and in the Columbia...
