Statistical self-similarity of hotspot seamount volumes modeled as self-similar criticality
S.F. Tebbens, S.M. Burroughs, C.C. Barton, D. F. Naar
2001, Geophysical Research Letters (28) 2711-2714
The processes responsible for hotspot seamount formation are complex, yet the cumulative frequency-volume distribution of hotspot seamounts in the Easter Island/Salas y Gomez Chain (ESC) is found to be well-described by an upper-truncated power law. We develop a model for hotspot seamount formation where uniform energy input produces events initiated...
Smectite diagenesis, pore-water freshening, and fluid flow at the toe of the Nankai wedge
K. M. Brown, D.M. Saffer, B.A. Bekins
2001, Earth and Planetary Science Letters (194) 97-109
The presence of low-chloride fluids in the lowermost sediments drilled at Ocean Drilling Program Site 808, at the Nankai accretionary wedge, has been considered as prime evidence for long-distance, lateral fluid flow from depth. Here, we re-evaluate the potential role of in situ reaction of smectite (S) to illite (I)...
New digital magnetic anomaly database for North America
C. A. Finn, M. Pilkington, A. Cuevas, I. Hernandez, Jaime Urrutia
2001, The Leading Edge (20) 870-872
The Geological Survey of Canada (GSC), U.S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM) are compiling an upgraded digital magnetic anomaly database and map for North America. This trinational project is expected to be completed by late 2002....
A portfolio approach to evaluating natural hazard mitigation policies: An application to lateral-spread ground failure in coastal California
R. L. Bernknopf, L.B. Dinitz, S.J.M. Rabinovici, A.M. Evans
2001, International Geology Review (43) 424-440
In the past, efforts to prevent catastrophic losses from natural hazards have largely been undertaken by individual property owners based on site—specific evaluations of risks to particular buildings. Public efforts to assess community vulnerability and encourage mitigation have focused on either aggregating site—specific estimates or adopting standards based upon broad...
Snapping turtles (Chelydra serpentina) as monitors for mercury contamination of aquatic environments
W.J. Golet, T.A. Haines
2001, Environmental Monitoring and Assessment (71) 211-220
We assessed the distribution of mercury in snapping turtles (Chelydra serpentina) by analyzing front shoulder muscle, back leg muscle, tail muscle, blood, liver, and marginal carapacial scute (shell) of 26 adult turtles from five small lakes. Total mercury concentration in muscle ranged from 50 to500 ng g−1 wet weight and was...
Mapping wildland fuels for fire management across multiple scales: integrating remote sensing, GIS, and biophysical modeling
Robert E. Keane, Robert E. Burgan, Jan W. Van Wagtendonk
2001, International Journal of Wildland Fire (10) 301-319
Fuel maps are essential for computing spatial fire hazard and risk and simulating fire growth and intensity across a landscape. However, fuel mapping is an extremely difficult and complex process requiring expertise in remotely sensed image classification, fire behavior, fuels modeling, ecology, and geographical information systems (GIS). This paper first...
Fish species composition two second-order headwater streams the North Central Appalachians ecoregion
M. N. DiLauro, R. M. Bennett
2001, Journal of Freshwater Ecology (16) 35-43
Fish species composition was determined for two second-order headwater streams within the North Central Appalachians ecoregion in northern Pennsylvania. The two streams were widely spaced geographically (over 193 km apart) and occurred in different drainage systems. Streams were sampled in the spring and fall over two years (1996–98) yielding similar...
Standard reference water samples for rare earth element determinations
P. L. Verplanck, Ronald C. Antweiler, D. Kirk Nordstrom, Howard E. Taylor
2001, Applied Geochemistry (16) 231-244
Standard reference water samples (SRWS) were collected from two mine sites, one near Ophir, CO, USA and the other near Redding, CA, USA. The samples were filtered, preserved, and analyzed for rare earth element (REE) concentrations (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb,...
Quiescent hydrogen sulfide and carbon dioxide degassing from Mount Baker, Washington
K.A. McGee, M.P. Doukas, T.M. Gerlach
2001, Geophysical Research Letters (28) 4479-4482
Volcanic H2S emission rate data are scant despite their importance in understanding magma degassing. We present results from direct airborne plume measurements of H2S and CO2 on a 21-orbit survey at eleven different altitudes around Mount Baker volcano in September 2000 utilizing instrumentation mounted in a light aircraft. Measured emission...
Utility of stable isotope analysis in studying foraging ecology of herbivores: Examples from moose and caribou
Merav Ben-David, Einav Shochat, Layne G. Adams
2001, Alces (37) 421-434
Recently, researchers emphasized that patterns of stable isotope ratios observed at the individual level are a result of an interaction between ecological, physiological, and biochemical processes. Isotopic models for herbivores provide additional complications because those mammals consume foods that have high variability in nitrogen concentrations. In addition, distribution of amino...
Chlorine-36, bromide, and the origin of spring water
S.N. Davis, L.D. Cecil, M. Zreda, S. Moysey
2001, Chemical Geology (179) 3-16
Natural ratios of chlorine-36 (36Cl) to stable chlorine (i.e., 36Cl/Cl ?? 10-15) vary in shallow groundwater of the United States from about 50 in coastal areas to about 1400 in the northern Rocky Mountains. Ratios lower than these indicate the presence of chloride (Cl-) that has been isolated from the...
Guidance of yearling shortnose and pallid sturgeon using vertical bar rack and louver arrays
B. Kynard, Martin Horgan
2001, North American Journal of Fisheries Management (21) 561-570
Some populations of shortnose sturgeon Acipenser brevirostrum and pallid sturgeon Scaphirhynchus albus have been divided by hydroelectric dams, and migration downstream past the dams likely continues. No protection for downstream migrants is presently available, and the behavior of sturgeon to guidance structures has not been studied. We conducted experiments in a 5.4-m-long × 1.5-m-wide...
A comparison of susceptibility to Myxobolus cerebralis among strains of rainbow trout and steelhead field and laboratory trials
Christine L. Densmore, V. S. Blazer, Deborah D. Cartwright, W. B. Schill, J. H. Schachte, C. J. Petrie, M.V. Batur, T.B. Waldrop, A. Mack, P.S. Pooler
2001, Journal of Aquatic Animal Health (13) 220-227
Three strains of rainbow trout and steelhead Oncorhynchus mykiss were evaluated for the presence of whirling disease in field and laboratory trials. In the field exposures, fingerling Salmon River steelhead and Cayuga Lake and Randolph strains of rainbow trout were placed in wire cages in an earthen, stream-fed pond in New York...
Survey protocol for assessment of endangered freshwater mussels the Allegheny River, Pennsylvania
D. R. Smith, R.F. Villella, D. P. Lemarie
2001, Journal of North American Benthological Society (20) 118-132
The United States Endangered Species Act (ESA) requires a biological assessment of any activity that is authorized, funded, or carried out by a federal agency and likely to affect a federally listed endangered species or its critical habitat. We developed a standardized survey protocol for biological assessments of the effects...
We still need Smokey Bear!
Jon E. Keeley
2001, Fire Management Today (61) 21-22
It was gratifying to see articles in recent issues of Fire Management Today clarifying the role of Smokey Bear in wildland fire management strategies (Baily 1999; Brown 1999). These articles clearly spelled out Smokey’s importance in reducing unplanned human-ignited wildland fires and rightly criticized attempts to detract from Smokey’s campaign...
Effect of land cover, habitat fragmentation and ant colonies on the distribution and abundance of shrews in southern California
Juha Laakkonen, Robert N. Fisher, Ted J. Case
2001, Journal of Animal Ecology (70) 776-788
Because effects of habitat fragmentation and anthropogenic disturbance on native animals have been relatively little studied in arid areas and in insectivores, we investigated the roles of different land covers, habitat fragmentation and ant colonies on the distribution and abundance of shrews, Notiosorex crawfordi and Sorex ornatus, in southern California.Notiosorex...
Pneumocystosis in wild small mammals from California
Juha Laakkonen, Robert N. Fisher, Ted J. Case
2001, Journal of Wildlife Diseases (37) 408-412
Cyst forms of the opportunistic fungal parasite Pneumocystis carinii were found in the lungs of 34% of the desert shrew, Notiosorex crawfordi (n = 59), 13% of the ornate shrew, Sorex ornatus (n = 55), 6% of the dusky-footed wood rat, Neotoma fuscipes (n = 16), 2.5% of the California meadow vole, Microtus californicus (n = 40), and 50% of the California pocket mouse, Chaetodipus...
Evolution of soils on quaternary reef terraces of Barbados, West Indies
D.R. Muhs
2001, Quaternary Research (56) 66-78
Soils on uplifted Quaternary reef terraces of Barbados, ???125,000 to ???700,000 yr old, form a climo-chronosequence and show changes in physical, chemical, and mineralogical properties with terrace age. Parent materials are dust derived from the Sahara, volcanic ash from the Lesser Antilles island arc, and detrital carbonate from the underlying...
Growth, biomass allocation and nutrient use efficiency in Cladium jamaicense and Typha domingensis as affected by phosphorus and oxygen availability
B. Lorenzen, H. Brix, I.A. Mendelssohn, K.L. McKee, S.L. Miao
2001, Aquatic Botany (70) 117-133
The effects of phosphorus (P) and oxygen availability on growth, biomass allocation and nutrient use efficiency in Cladium jamaicense Crantz and Typha domingensis Pers. were studied in a growth facility equipped with steady-state hydroponic rhizotrons. The treatments included four P concentrations (10, 40, 80 and 500 ??g I-1) and two...
High resolution seismic-reflection imaging of shallow deformation beneath the northeast margin of the Manila high at Big Lake, Arkansas
J. K. Odum, W. J. Stephenson, R. A. Williams, D. M. Worley, Margaret J. Guccione, R. B. Van Arsdale
2001, Engineering Geology (62) 91-103
The Manila high, an elliptical area 19 km long (N-S) by 6 km wide (E-W) located west-southwest of Big Lake. Arkansas, has less than 3 m of topographic relief. Geomorphic, stratigraphic and chronology data indicate that Big Lake formed during at least two periods of Holocene uplift and subsequent damming...
Geologic history of the polar regions of Mars based on Mars Global survey data. I. Noachian and Hesperian Periods
K. L. Tanaka, E.J. Kolb
2001, Icarus (154) 3-21
During the Noachian Period, the south polar region of Mars underwent intense cratering, construction of three groups of volcanoes, widespread contractional deformation, resurfacing of low areas, and local dissection of valley networks; no evidence for polar deposits, ice sheets, or glaciation is recognized. South polar Hesperian geology is broadly characterized...
Pesticides and amphibian declines in California, USA
Donald W. Sparling, Gary M. Fellers, Laura McConnell
2001, Environmental Toxicology and Chemistry (20) 1591-1595
Several species of anuran amphibians have undergone drastic population declines in the western United States over the last 10 to 15 years. In California, the most severe declines are in the Sierra Mountains east of the Central Valley and downwind of the intensely agricultural San Joaquin Valley. In contrast, coastal...
Physiological variation among native and exotic winter annuals associated with microphytic soil crusts in the Mojave Desert
Lesley DeFalco, James K. Detling, C. Richard Tracy, Steven D. Warren
2001, Plant and Soil (234) 1-14
Microbiotic crusts are important components of many aridland soils. Research on crusts typically focuses on the increase in soil fertility due to N-fixing micro-organisms, the stabilization of soils against water and wind erosion and the impact of disturbance on N-cycling. The effect of microbiotic crusts on the associated plant community...
From open to closed canopy: A century of change in Douglas-fir forest, Orcas Island, Washington
D. L. Peterson, R.D. Hammer
2001, Northwest Science (75) 262-269
During the past century, forest structure on south-facing slopes of Mount Constitution, Orcas Island, Washington, has changed from open-grown Douglas-fir (Pseudotsuga menziesii) mixed with prairie to primarily closed canopy forest. Density of open-grown Douglas-fir was approximately 7 stems/ha in the 19th century, while current density of trees in closed-canopy mature forest is 426 stems/ha....
Development of channel organization and roughness following sediment pulses in single‐thread, gravel bed rivers
Mary Ann Madej
2001, Water Resources Research (37) 2259-2272
Large, episodic inputs of coarse sediment (sediment pulses) in forested, mountain streams may result in changes in the size and arrangement of bed forms and in channel roughness. A conceptual model of channel organization delineates trajectories of response to sediment pulses for many types of gravel bed channels. Channels exhibited...
