Correlates of biological soil crust abundance across a continuum of spatial scales: Support for a hierarchical conceptual model
M. A. Bowker, J. Belnap, D. W. Davidson, H. Goldstein
2006, Journal of Applied Ecology (43) 152-163
1. Desertification negatively impacts a large proportion of the global human population and > 30% of the terrestrial land surface. Better methods are needed to detect areas that are at risk of desertification and to ameliorate desertified areas. Biological soil crusts are an important soil lichen-moss-microbial community that can be...
Partitioning evapotranspiration in sparsely vegetated rangeland using a portable chamber
David I. Stannard, Mark A. Weltz
2006, Water Resources Research (42)
A portable chamber was used to separate evapotranspiration (ET) from a sparse, mixed‐species shrub canopy in southeastern Arizona, United States, into vegetation and soil components. Chamber measurements were made of ET from the five dominant species, and from bare soil, on 3 days during the monsoon season when the soil surface was...
Scaling uncertainties in estimating canopy foliar maintenance respiration for black spruce ecosystems in Alaska
X. Zhang, A. D. McGuire, Roger W. Ruess
2006, Mitigation and Adaptation Strategies for Global Change (11) 147-174
A major challenge confronting the scientific community is to understand both patterns of and controls over spatial and temporal variability of carbon exchange between boreal forest ecosystems and the atmosphere. An understanding of the sources of variability of carbon processes at fine scales and how these contribute to uncertainties in...
Is a healthy ecosystem one that is rich in parasites?
Peter J. Hudson, Andrew P. Dobson, Kevin D. Lafferty
2006, Trends in Ecology and Evolution (21) 381-385
Historically, the role of parasites in ecosystem functioning has been considered trivial because a cursory examination reveals that their relative biomass is low compared with that of other trophic groups. However there is increasing evidence that parasite-mediated effects could be significant: they shape host population dynamics, alter interspecific competition, influence...
Field tests of acoustic telemetry for a portable coastal observatory
M. Martini, B. Butman, J. Ware, D. Frye
2006, Conference Paper, OCEANS 2006
Long-term field tests of a low-cost acoustic telemetry system were carried out at two sites in Massachusetts Bay. At each site, an acoustic Doppler current profiler mounted on a bottom tripod was fitted with an acoustic modem to transmit data to a surface buoy; electronics mounted on the buoy relayed...
The role of fire refugia in the distribution of Pinus sabiniana (Pinaceae) in the southern Sierra Nevada
Dylan W. Schwilk, Jon E. Keeley
2006, Madroño (53) 364-372
Although widespread throughout the interior foothills of central and northern California, Pinus sabiniana Dougl. has a disjunct distribution in the southern Sierra Nevada, where it is abundant in the Kern River and Tule River watersheds, but is absent from the Kaweah River watershed between 36° and 37°N. This gap in the pine's...
A mid-holocene fauna from Bear Den Cave, Sequoia National Park, California
Jim I. Mead, Thomas W. McGinnis, Jon E. Keeley
2006, Bulletin, Southern California Academy of Sciences (105) 43-58
Test excavation of floor fill deposits in the first room in Bear Den Cave, Sequoia National Park, produced fossiliferous sediments down to at least 40 cm depth. Radiocarbon analysis of charcoal from this layer indicates an early-middle Holocene age of 7220 CAL BP. The fossil accumulation represents prey recovered from...
Interrelationships of Denali's large mammal community
Layne G. Adams, Thomas J. Meier, Patricia Owen, Gretchen H. Roffler
2006, Alaska Park Science (5) 36-40
Along with its sweeping mountain landscapes, Denali National Park and Preserve (Denali) is probably best known for opportunities to observe the large mammals common to Interior Alaska. Locally known as the “Big Five,” gray wolves (Canis lupus), grizzly bears (Ursus arctos),moose (Alces alces), caribou (Rangifer tarandus) and Dall sheep (Ovis...
Fault dating in the Canadian Rocky Mountains: Evidence for late Cretaceous and early Eocene orogenic pulses
B.A. van der Pluijm, P.J. Vrolijk, D.R. Pevear, C.M. Hall, J. Solum
2006, Geology (34) 837-840
Fault rocks from the classic Rocky Mountain foreland fold-and-thrust belt in south-western Canada were dated by Ar analysis of clay grain-size fractions. Using X-ray diffraction quantification of the detrital and authigenic component of each fraction, these determinations give ages for individual faults in the area (illite age analysis). The resulting...
Bedrock formation at Meridiani Planum
S. W. Squyres, O. Aharonson, R. E. Arvidson, J.F. Bell III, P. R. Christensen, B.C. Clark, J.A. Crisp, W. Farrand, T. Glotch, M.P. Golombek, J. Grant, J. Grotzinger, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, A.H. Knoll, S. M. McLennan, H.Y. McSween, Johnnie N. Moore, J. W. Rice Jr., N. Tosca
2006, Nature (443) E1-E2
The Mars Exploration Rover Opportunity discovered sulphate-rich sedimentary rocks at Meridiani Planum on Mars, which are interpreted by McCollom and Hynek as altered volcanic rocks. However, their conclusions are derived from an incorrect representation of our depositional model, which is upheld by more recent Rover data. We contend that all the...
Odontomariinae, a new middle paleozoic subfamily of slit-bearing euophaloidean gastropods (Euophalomorpha, Gastropoda)
J. Fryda, D. Heidelberger, R. B. Blodgett
2006, Neues Jahrbuch fur Geologie und Palaontologie - Monatshefte 225-248
A new subfamily, the Odontomariinae subfam. nov., is established herein for a distinctive group of uncoiled, slit-bearing Middle Devonian euomphalid gastropods. Its taxonomic position is based on the recent discovery of open coiled protoconchs and it is placed within the Euomphalomorpha. The genera Odontomaria Odontomaria C. F. Roemer and Tubiconcha...
MMI attenuation and historical earthquakes in the basin and range province of western North America
W. H. Bakun
2006, Bulletin of the Seismological Society of America (96) 2206-2220
Earthquakes in central Nevada (1932-1959) were used to develop a modified Mercalli intensity (MMI) attenuation model for estimating moment magnitude M for earthquakes in the Basin and Range province of interior western North America. M is 7.4-7.5 for the 26 March 1872 Owens Valley, California, earthquake, in agreement with Beanland...
Predictable hotspots and foraging habitat of the endangered short-tailed albatross (Phoebastria albatrus) in the North Pacific: Implications for conservation
John F. Piatt, J. Wetzel, K. Bell, A.R. DeGange, G.R. Balogh, G.S. Drew, T. Geernaert, C. Ladd, G.V. Byrd
2006, Deep-Sea Research Part II: Topical Studies in Oceanography (53) 387-398
The short-tailed albatross (Phoebastria albatrus) is a rare and endangered seabird that ranges widely over the northern North Pacific. Populations are slowly recovering but birds face several threats at sea, in particular the incidental capture of birds in long-line fisheries. Conservation efforts are hampered by a lack of information about...
Evaluation of a recirculating pond system for rearing juvenile freshwater mussels at White Sulphur Springs National Fish Hatchery, West Virginia, U.S.A.
A. Mummert, T.J. Newcomb, R. J. Neves, B. Parker
2006, American Malacological Bulletin (21) 1-10
A recirculating double-pond system at White Sulphur Springs National Fish Hatchery in West Virginia, U.S.A., was evaluated for suitability for culturing juvenile freshwater mussels. Newly metamorphosed juveniles of Villosa iris and Lampsilis fasciola were placed in the system, and their growth and survival were evaluated for 94 days. Throughout the...
Northern Florida reef tract benthic metabolism scaled by remote sensing
J. C. Brock, K. K. Yates, R. B. Halley, I. B. Kuffner, C. W. Wright, B.G. Hatcher
2006, Marine Ecology Progress Series (312) 123-139
Holistic rates of excess organic carbon production (E) and calcification for a 0.5 km2 segment of the backreef platform of the northern Florida reef tract (NFRT) were estimated by combining biotope mapping using remote sensing with community metabolic rates determined with a benthic incubation system. The use of ASTER multispectral...
Expert forecasts and the emergence of water scarcity on public agendas
E.A. Graffy
2006, Society and Natural Resources (19) 465-472
Expert forecasts of worldwide water scarcity depict conditions that call for proactive, preventive, coordinated water governance, but they have not been matched by public agendas of commensurate scope and urgency in the United States. This disconnect can not be adequately explained without some attention to attributes of forecasts themselves. I...
Paleoclimatic evidence for future ice-sheet instability and rapid sea-level rise
J. T. Overpeck, B. L. Otto-Bliesner, G. H. Miller, D.R. Muhs, R. B. Alley, J.T. Kiehl
2006, Science (311) 1747-1750
Sea-level rise from melting of polar ice sheets is one of the largest potential threats of future climate change. Polar warming by the year 2100 may reach levels similar to those of 130,000 to 127,000 years ago that were associated with sea levels several meters above modern levels; both the...
Introduction
M.L. Brooks
2006, Book chapter, The Use of Fire as a Tool for Controlling Invasive Plants: Cal-IPC Publication 2006-01
No abstract available at this time...
Radiative transfer modeling of dust-coated Pancam calibration target materials: Laboratory visible/near-infrared spectrogoniometry
J. R. Johnson, J. Sohl-Dickstein, W.M. Grundy, R. E. Arvidson, J.F. Bell III, P. R. Christensen, T. Graff, E.A. Guinness, K. Kinch, Robert Morris, M.K. Shepard
2006, Journal of Geophysical Research E: Planets (111)
Laboratory visible/near-infrared multispectral observations of Mars Exploration Rover Pancam calibration target materials coated with different thicknesses of Mars spectral analog dust were acquired under variable illumination geometries using the Bloomsburg University Goniometer. The data were fit with a two-layer radiative transfer model that combines a Hapke formulation for the dust...
First USGS urban seismic hazard maps predict the effects of soils
C.H. Cramer, J.S. Gomberg, E.S. Schweig, B.A. Waldron, K. Tucker
2006, Seismological Research Letters (77) 23-29
Probabilistic and scenario urban seismic hazard maps have been produced for Memphis, Shelby County, Tennessee covering a six-quadrangle area of the city. The nine probabilistic maps are for peak ground acceleration and 0.2 s and 1.0 s spectral acceleration and for 10%, 5%, and 2% probability of being exceeded in...
Parameterization and simulation of near bed orbital velocities under irregular waves in shallow water
B. Elfrink, D.M. Hanes, B.G. Ruessink
2006, Coastal Engineering (53) 915-927
A set of empirical formulations is derived that describe important wave properties in shallow water as functions of commonly used parameters such as wave height, wave period, local water depth and local bed slope. These wave properties include time varying near-bed orbital velocities and statistical properties such as the distribution...
Drainage effects on the transient, near-surface hydrologic response of a steep hillslope to rainfall: Implications for slope stability, Edmonds, Washington, USA
G. Biavati, J. W. Godt, J.P. McKenna
2006, Natural Hazards and Earth System Sciences (6) 343-355
Shallow landslides on steep (>25??) hillsides along Puget Sound have resulted in occasional loss of life and costly damage to property during intense or prolonged rainfall. As part of a larger project to assess landslide hazards in the Seattle area, the U.S. Geological Survey instrumented two coastal bluff sites in...
Spectrophotometric properties of materials observed by Pancam on the Mars Exploration Rovers: 1. Spirit
J. R. Johnson, W.M. Grundy, M.T. Lemmon, J.F. Bell III, M. J. Johnson, R.G. Deen, R. E. Arvidson, W. H. Farrand, E.A. Guinness, A. G. Hayes, Kenneth E. Herkenhoff, F. Seelos IV, J. Soderblom, S. Squyres
2006, Journal of Geophysical Research E: Planets (111)
Multispectral observations of rocks and soils were acquired under varying illumination and viewing geometries in visible/near‐infrared wavelengths by the Panoramic Camera (Pancam) on the Spirit Mars Exploration Rover to provide constraints on the physical and mineralogical nature of geologic materials in Gusev Crater. Data sets were acquired at six sites...
Sexual dimorphism of the internal mandibular chamber in Fayum Pliohyracidae (Mammalia)
de Blieux, M.R. Baumrind, E.L. Simons, P.S. Chatrath, G.E. Meyer, Y.S. Attia
2006, Journal of Vertebrate Paleontology (26) 160-169
An internal mandibular fenestra and chamber are found in many fossil hyracoids. The internal mandibular fenestra is located on the lingual surface of the mandibular corpus and opens into a chamber within the mandible. The mandibular chamber is maximally developed in late Eocene Thyrohyrax meyeri and early Oligocene Thyrohyrax domorictus...
Extreme plasticity in thermoregulatory behaviors of free-ranging black-tailed prairie dogs
E.M. Lehmer, L.T. Savage, M.F. Antolin, E. Biggins
2006, Physiological and Biochemical Zoology (79) 454-467
In the natural environment, hibernating sciurids generally remain dormant during winter and enter numerous deep torpor bouts from the time of first immergence in fall until emergence in spring. In contrast, black-tailed prairie dogs (Cynomys ludovicianus) remain active throughout winter but periodically enter short and shallow bouts of torpor. While...
