How should environmental stress affect the population dynamics of disease?
Kevin D. Lafferty, Robert D. Holt
2003, Ecology Letters (6) 654-664
We modelled how stress affects the population dynamics of infectious disease. We were specifically concerned with stress that increased susceptibility of uninfected hosts when exposed to infection. If such stresses also reduced resources, fecundity and/or survivorship, there was a reduction in the host carrying capacity. This lowered the contact between...
Measurements of thermal updraft intensity over complex terrain using American white pelicans and a simple boundary-layer forecast model
H.D. Shannon, G.S. Young, M. Yates, Mark R. Fuller, W. Seegar
2003, Boundary-Layer Meteorology (104) 167-199
An examination of boundary-layer meteorological and avian aerodynamic theories suggests that soaring birds can be used to measure the magnitude of vertical air motions within the boundary layer. These theories are applied to obtain mixed-layer normalized thermal updraft intensity over both flat and complex terrain from the climb rates of...
The use of sea ice habitat by female polar bears in the Beaufort Sea
George M. Durner, Steven C. Amstrup, Ryan M. Nielson, Trent McDonald
2003, Conference Paper, Ninth information transfer meeting and Barrow information update meeting: Final proceedings (MMS 2003-042)
Polar bears (Ursus maritimus) depend on ice-covered seas to satisfy life history requirements. Modern threats to polar bears include oil spills in the marine environment and changes in ice composition resulting from climate change. Managers need practical models that explain the distribution of bears in order to assess the impacts...
Origin of minerals in joint and cleat systems of the Pottsville Formation, Black Warrior basin, Alabama: Implications for coalbed methane generation and production
Janet K. Pitman, J.C. Pashin, J. R. Hatch, M. B. Goldhaber
2003, American Association of Petroleum Geologists Bulletin (87) 713-731
Coalbed methane is produced from naturally fractured strata in the lower Pennsylvanian Pottsville Formation in the eastern part of the Black Warrior basin, Alabama. Major fracture systems include orthogonal fractures, which consist of systematic joints in siliciclastic strata and face...
A numerical simulation of magma motion, crustal deformation, and seismic radiation associated with volcanic eruptions
T. Nishimura, B. Chouet
2003, Geophysical Journal International (153) 699-718
The finite difference method is used to calculate the magma dynamics, seismic radiation, and crustal deformation associated with a volcanic eruption. The model geometry consists of a cylindrical reservoir and narrow cylindrical conduit embedded in a homogeneous crust. We consider two models of eruption. In the first model, a lid...
A multiscaled model of southwestern willow flycatcher breeding habitat
J.R. Hatten, C.E. Paradzick
2003, Journal of Wildlife Management (67) 774-788
The southwestern willow flycatcher (SWFL; Empidonax traillii extimus) is an endangered songbird whose habitat has declined dramatically over the last century. Understanding habitat selection patterns and the ability to identify potential breeding areas for the SWFL is crucial to the management and conservation of this species. We developed a multiscaled...
A mechanism for sustained groundwater pressure changes induced by distant earthquakes
E. E. Brodsky, E. Roeloffs, D. Woodcock, I. Gall, M. Manga
2003, Journal of Geophysical Research B: Solid Earth (108)
Large sustained well water level changes (>10 cm) in response to distant (more than hundreds of kilometers) earthquakes have proven enigmatic for over 30 years. Here we use high sampling rates at a well near Grants Pass, Oregon, to perform the first simultaneous analysis of both the dynamic response of...
Source model for the Mw 6.7, 23 October 2002, Nenana Mountain earthquake (Alaska) from InSAR
Tim J. Wright, Z. Lu, Charles Wicks
2003, Geophysical Research Letters (30) 12-1-12-4
The 23 October 2002 Nenana Mountain Earthquake (Mw ∼ 6.7) occurred on the Denali Fault (Alaska), to the west of the Mw ∼ 7.9 Denali Earthquake that ruptured the same fault 11 days later. We used 6 interferograms, constructed using radar images from the Canadian Radarsat-1 and European ERS-2 satellites,...
Stratigraphy and palaeoclimatic significance of Late Quaternary loess-palaeosol sequences of the Last Interglacial-Glacial cycle in central Alaska
D.R. Muhs, T. A. Ager, E. Arthur Bettis III, J. McGeehin, J.M. Been, J. E. Beget, M.J. Pavich, Thomas W. Stafford Jr., D.A.S.P. Stevens
2003, Quaternary Science Reviews (22) 1947-1986
Loess is one of the most widespread subaerial deposits in Alaska and adjacent Yukon Territory and may have a history that goes back 3 Ma. Based on mineralogy and major and trace element chemistry, central Alaskan loess has a composition that is distinctive from other loess bodies of the world,...
Life history, diversity and distribution: A study of Japanese pteridophytes
Q. Guo, Masako Kato, R. E. Ricklefs
2003, Ecography (26) 129-138
Many studies address the relationships between diversity or distribution and attributes of the physical environment. However, how these relationships are connected to variation in life history is poorly understood. This is particularly true in the case of pteridophytes. Japanese ferns and their allies comprise one of the best-known pteridophyte floras...
Modeling aqueous ferrous iron chemistry at low temperatures with application to Mars
G.M. Marion, D.C. Catling, J.S. Kargel
2003, Geochimica et Cosmochimica Acta (67) 4251-4266
Major uncertainties exist with respect to the aqueous geochemical evolution of the Martian surface. Considering the prevailing cryogenic climates and the abundance of salts and iron minerals on Mars, any attempt at comprehensive modeling of Martian aqueous chemistry should include iron chemistry and be valid at low temperatures and high...
Statistical power for detecting trends with applications to seabird monitoring
Scott A. Hatch
2003, Biological Conservation (111) 317-329
Power analysis is helpful in defining goals for ecological monitoring and evaluating the performance of ongoing efforts. I examined detection standards proposed for population monitoring of seabirds using two programs (MONITOR and TRENDS) specially designed for power analysis of trend data. Neither program models within- and among-years components of variance...
U.S. Geological Survey Greater Everglades Science Program: 2002 Biennial Report
Arturo E. Torres, Aaron L. Higer, Heather S. Henkel, Patsy R. Mixson, Jane R. Eggleston, Teresa L. Embry, Gail Clement
2003, Open-File Report 03-54
IntroductionThe U.S. Geological Survey (USGS) conducts scientific investigations in south Florida to improve society’s understanding of the environment and assist in the sustainable use, protection, and restoration of the Everglades and other ecosystems within the region. The investigations summarized in this document have been carried out under the Greater Everglades...
Mechanism for generating the anomalous uplift of oceanic core complexes: Atlantis Bank, southwest Indian Ridge
A.G. Baines, Michael J. Cheadle, H.J.B. Dick, A.H. Scheirer, Barbara E. John, N.J. Kusznir, T. Matsumoto
2003, Geology (31) 1105-1108
Atlantis Bank is an anomalously uplifted oceanic core complex adjacent to the Atlantis II transform, on the southwest Indian Ridge, that rises >3 km above normal seafloor of the same age. Models of flexural uplift due to detachment faulting can account for ???1 km of this uplift. Postdetachment normal faults...
Chlorine-36 data at Yucca Mountain: Statistical tests of conceptual models for unsaturated-zone flow
K. Campbell, A. Wolfsberg, J. Fabryka-Martin, D. Sweetkind
2003, Journal of Contaminant Hydrology (62-63) 43-61
An extensive set of chlorine-36 (36Cl) data has been collected in the Exploratory Studies Facility (ESF), an 8-km-long tunnel at Yucca Mountain, Nevada, for the purpose of developing and testing conceptual models of flow and transport in the unsaturated zone (UZ) at this site. At several locations, the measured values...
Evolution of CAM and C4 carbon-concentrating mechanisms
Jon E. Keeley, Philip W. Rundel
2003, International Journal of Plant Sciences (164) 555-577
Mechanisms for concentrating carbon around the Rubisco enzyme, which drives the carbon-reducing steps in photosynthesis, are widespread in plants; in vascular plants they are known as crassulacean acid metabolism (CAM) and C4 photosynthesis. CAM is common in desert succulents, tropical epiphytes, and aquatic plants and is characterized by nighttime fixation...
Effects of lampricide exposure on the survival, growth, and behavior of the unionid mussels Elliptio complanata and Pyganadon cataracta
D. L. Waller, T.D. Bills, M.A. Boogaard, D.A. Johnson, T.C.J. Doolittle
2003, Journal of Great Lakes Research (29 Suppl. 1) 542-551
The effects of a 12-h exposure to the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) and a combination of TFM and 1% niclosamide (active ingredient in Bayluscide 70% wettable powder) on the short and long-term (10 mo post exposure) survival and behavior of two unionid freshwater mussel species Elliptio complanata and Pyganadon cataracta were...
Relationship among side channels, fish assemblages, and environmental gradients in the unimpounded Upper Mississippi River
V.A. Barko, D.P. Herzog
2003, Journal of Freshwater Ecology (18) 377-382
We analyzed fish abundance and environmental data collected over nine years from six side channels of the unimpounded upper Mississippi River between river km 46.7 and 128.7. A partial canonical correspondence analysis revealed differences in fish assemblages and environmental factors correlated with the six side channels. Fishes correlated with open...
Surface seismic refraction/reflection measurement determinations of potential site resonances and the areal uniformity of NEHRP site class D in Memphis, Tennessee
R. A. Williams, S. Wood, W. J. Stephenson, J. K. Odum, M. E. Meremonte, R. Street, D. M. Worley
2003, Earthquake Spectra (19) 159-189
We determined S-wave velocities (Vs) to about 40-m depth at 65 locations in the Memphis-Shelby County, Tennessee, area. The Vs measurements were made using high-resolution seismic refraction and reflection methods on the ground surface. We find a clear difference in the Vs profiles between sites located on the Mississippi River...
Helping to combat chronic wasting disease
Water Resources Division, U.S. Geological Survey
2003, Fact Sheet 2005-3076
Chronic wasting disease (CWD) is a disease of the nervous system that results in distinctive brain lesions. CWD affects elk, white-tailed deer, and mule deer, but has not been documented in livestock or humans. The origins of the disease, as well as the modes of transmission, remain unknown. Infected deer...
Lithospheric structure, composition, and thermal regime of the East European Craton: Implications for the subsidence of the Russian platform
I.M. Artemieva
2003, Earth and Planetary Science Letters (213) 431-446
A new mechanism for Paleozoic subsidence of the Russian, or East European, platform is suggested, since a model of lithosphere tilting during the Uralian subduction does not explain the post-Uralian sedimentation record. Alternatively, I propose that the Proterozoic and Paleozoic rifting (when a platform-scale Central Russia rift system and a...
Seismic evidence for widespread serpentinized forearc upper mantle along the Cascadia margin
T.M. Brocher, T. Parsons, A.M. Trehu, C.M. Snelson, M. A. Fisher
2003, Geology (31) 267-270
Petrologic models suggest that dehydration and metamorphism of subducting slabs release water that serpentinizes the overlying forearc mantle. To test these models, we use the results of controlled-source seismic surveys and earthquake tomography to map the upper mantle along the Cascadia margin forearc. We find anomalously low upper-mantle velocities and/or...
Global occurrence of tellurium-rich ferromanganese crusts and a model for the enrichment of tellurium
J.R. Hein, A. Koschinsky, A. N. Halliday
2003, Geochimica et Cosmochimica Acta (67) 1117-1127
Hydrogenetic ferromanganese oxyhydroxide crusts (Fe-Mn crusts) precipitate out of cold ambient ocean water onto hard-rock surfaces (seamounts, plateaus, ridges) at water depths of about 400 to 4000 m throughout the ocean basins. The slow-growing (mm/Ma) Fe-Mn crusts concentrate most elements above their mean...
Fish faunal resurgence in Lake Nabugabo, East Africa
L.J. Chapman, Colin A. Chapman, P. J. Schofield, J.P. Olowo, L.S. Kaufman, O. Seehausen, R. Ogutu-Ohwayo.
2003, Conservation Biology (17) 500-511
In Lake Nabugabo, Uganda, a small satellite of the equatorial Lake Victoria, approximately 50% of the indigenous fish species disappeared from the open waters subsequent to establishment of the introduced predatory Nile perch ( Lates niloticus ). However, several of these species persisted in wetland refugia. Over the past decade, Nile perch...
Lithospheric roots beneath western Laurentia: The geochemical signal in mantle garnets
D. Canil, D.J. Schulze, D. Hall, B. C. Hearn Jr., S.M. Milliken
2003, Canadian Journal of Earth Sciences (40) 1027-1051
This study presents major and trace element data for 243 mantle garnet xenocrysts from six kimberlites in parts of western North America. The geochemical data for the garnet xenocrysts are used to infer the composition, thickness, and tectonothermal affinity of the mantle lithosphere beneath western Laurentia at the time of...
