VP Structure of Mount St. Helens, Washington, USA, imaged with local earthquake tomography
G.P. Waite, S.C. Moran
2009, Journal of Volcanology and Geothermal Research (182) 113-122
We present a new P-wave velocity model for Mount St. Helens using local earthquake data recorded by the Pacific Northwest Seismograph Stations and Cascades Volcano Observatory since the 18 May 1980 eruption. These data were augmented with records from a dense array of 19 temporary stations deployed during the second...
Effects of chemical immobilization on survival of African buffalo in the Kruger National Park
W.C. Oosthuizen, P.C. Cross, J.A. Bowers, C. Hay, M.R. Ebinger, P. Buss, M. Hofmeyr, E.Z. Cameron
2009, Journal of Wildlife Management (73) 149-153
Capturing, immobilizing, and fitting radiocollars are common practices in studies of large mammals, but success is based on the assumptions that captured animals are representative of the rest of the population and that the capture procedure has negligible effects. We estimated effects of chemical immobilization on mortality rates of African...
New light on a dark subject: On the use of fluorescence data to deduce redox states of natural organic matter (NOM)
Donald L. Macalady, Katherine Walton-Day
2009, Aquatic Sciences (71) 135-143
This paper reports the use of excitation-emission matrix fluorescence spectroscopy (EEMS), parallel factor statistical analysis (PARAFAC), and oxidation-reduction experiments to examine the effect of redox conditions on PARAFAC model results for aqueous samples rich in natural organic matter. Fifty-four aqueous samples from 11 different geographic locations and two plant extracts...
Using nitrogen stable isotopes to detect longdistance movement in a threatened cutthroat trout (Oncorhynchus clarkii utah)
A.J. Sepulveda, W.T. Colyer, W.H. Lowe, M.R. Vinson
2009, Canadian Journal of Fisheries and Aquatic Sciences (66) 672-682
Interior cutthroat trout occupy small fractions of their historic ranges and existing populations often are relegated to headwater habitats. Conservation requires balancing protection for isolated genetically pure populations with restoration of migratory life histories by reconnecting corridors between headwater and mainstem habitats. Identification of alternative life history strategies within a...
Monitoring benthic aIgal communides: A comparison of targeted and coefficient sampling methods
Matthew S. Edwards, M. Tim Tinker
2009, Algae (24) 111-120
Choosing an appropriate sample unit is a fundamental decision in the design of ecological studies. While numerous methods have been developed to estimate organism abundance, they differ in cost, accuracy and precision.Using both field data and computer simulation modeling, we evaluated the costs and benefits associated with two methods commonly...
Hierarchical spatial genetic structure of Common Eiders (Somateria mollissima) breeding along a migratory corridor
Sarah A. Sonsthagen, Sandra L. Talbot, Richard B. Lanctot, Kim T. Scribner, Kevin G. McCracken
2009, The Auk (126) 744-754
Documentation of spatial genetic discordance among breeding populations of Arctic-nesting avian species is important, because anthropogenic change is altering environmental linkages at micro- and macrogeographic scales. We estimated levels of population subdivision within Pacific Common Eiders (Somateria mollissima v-nigrum) breeding on 12 barrier islands in the western...
Influence of resolution in irrigated area mapping and area estimation
N.M. Velpuri, P.S. Thenkabail, M.K. Gumma, C. Biradar, V. Dheeravath, P. Noojipady, L. Yuanjie
2009, Photogrammetric Engineering and Remote Sensing (75) 1383-1395
The overarching goal of this paper was to determine how irrigated areas change with resolution (or scale) of imagery. Specific objectives investigated were to (a) map irrigated areas using four distinct spatial resolutions (or scales), (b) determine how irrigated areas change with resolutions, and (c) establish the causes of differences...
Dipping-interface mapping using mode-separated Rayleigh waves
Y. Luo, J. Xia, Y. Xu, C. Zeng, R. D. Miller, Q. Liu
2009, Pure and Applied Geophysics (166) 353-374
Multichannel analysis of surface waves (MASW) method is a non-invasive geophysical technique that uses the dispersive characteristic of Rayleigh waves to estimate a vertical shear (S)-wave velocity profile. A pseudo-2D S-wave velocity section is constructed by aligning 1D S-wave velocity profiles at the midpoint of each receiver spread that are...
CHRONOS architecture: Experiences with an open-source services-oriented architecture for geoinformatics
D. Fils, C. Cervato, J. Reed, P. Diver, X. Tang, G. Bohling, D. Greer
2009, Computers & Geosciences (35) 774-782
CHRONOS's purpose is to transform Earth history research by seamlessly integrating stratigraphic databases and tools into a virtual on-line stratigraphic record. In this paper, we describe the various components of CHRONOS's distributed data system, including the encoding of semantic and descriptive data into a service-based architecture. We give examples of...
Modeling fuel succession
Brett Davis, Jan W. Van Wagtendonk, Jen Beck, Kent A. van Wagtendonk
2009, Fire Management Today (69) 18-21
Surface fuels data are of critical importance for supporting fire incident management, risk assessment, and fuel management planning, but the development of surface fuels data can be expensive and time consuming. The data development process is extensive, generally beginning with acquisition of remotely sensed spatial data such as aerial photography...
Improving conceptual models of water and carbon transfer through peat
Jeffery M. McKenzie, Donald I. Siegel, Donald O. Rosenberry
Andrew J. Baird, Lisa R. Belyea, Xavier Comas, A.S. Reeve, Lee D. Slater, editor(s)
2009, Book chapter, Carbon cycling in northern peatlands: Geophysical Monograph Series
Northern peatlands store 500 × 1015 g of organic carbon and are very sensitive to climate change. There is a strong conceptual model of sources, sinks, and pathways of carbon within peatlands, but challenges remain both in understanding the hydrogeology and the linkages between carbon cycling and peat pore water...
Simulated dynamics of carbon stocks driven by changes in land use, management and climate in a tropical moist ecosystem of Ghana
Z. Tan, S. Liu, L.L. Tieszen, E. Tachie-Obeng
2009, Agriculture, Ecosystems and Environment (130) 171-176
Sub-Saharan Africa is large and diverse with regions of food insecurity and high vulnerability to climate change. This project quantifies carbon stocks and fluxes in the humid forest zone of Ghana, as a part of an assessment in West Africa. The General Ensemble biogeochemical Modeling System (GEMS) was used to...
Oxygen and hydrogen isotope fractionation in serpentine-water and talc-water systems from 250 to 450 °C, 50 MPa
Peter J. Saccocia, Jeffrey S. Seewald, Wayne C. Shanks III
2009, Geochimica et Cosmochimica Acta (73) 6789-6804
Oxygen and hydrogen isotope fractionation factors in the talc–water and serpentine–water systems have been determined by laboratory experiment from 250 to 450 °C at 50 MPa using the partial exchange technique. Talc was synthesized from brucite + quartz, resulting in nearly 100% exchange during reaction at 350 and 450 °C. For serpentine, D–H exchange was...
Geospatial Data Used in Water-Level and Land-Subsidence Studies in the Mojave River and Morongo Groundwater Basins for 2008
Carolyn Glockhoff, Christina L. Stamos
2009, Report
During 2008, the U.S. Geological Survey and other agencies made approximately 2,500 water-level measurements in the Mojave River and Morongo groundwater basins. These data document recent conditions and, when compared with previous data, changes in groundwater levels. A water-level contour map was drawn using data from about 700 wells, providing...
Seismic analysis of clinoform depositional sequences and shelf-margin trajectories in Lower Cretaceous (Albian) strata, Alaska North Slope
David W. Houseknecht, Kenneth J. Bird, Christopher J. Schenk
2009, Basin Research (21) 644-654
Lower Cretaceous strata beneath the Alaska North Slope include clinoform depositional sequences that filled the western Colville foreland basin and overstepped the Beaufort rift shoulder. Analysis of Albian clinoform sequences with two‐dimensional (2D) seismic data resulted in the recognition of seismic facies inferred to represent lowstand, transgressive and highstand systems...
A method for assigning species into groups based on generalized Mahalanobis distance between habitat model coefficients
C.J. Williams, P.J. Heglund
2009, Environmental and Ecological Statistics (16) 495-513
Habitat association models are commonly developed for individual animal species using generalized linear modeling methods such as logistic regression. We considered the issue of grouping species based on their habitat use so that management decisions can be based on sets of species rather than individual species. This research was motivated...
Predatory senescence in ageing wolves
D.R. MacNulty, D.W. Smith, J.A. Vucetich, L.D. Mech, D.R. Stahler, C. Packer
2009, Ecology Letters (12) 1347-1356
It is well established that ageing handicaps the ability of prey to escape predators, yet surprisingly little is known about how ageing affects the ability of predators to catch prey. Research into long-lived predators has assumed that adults have uniform impacts on prey regardless of age. Here we use longitudinal...
Evolutionary dynamics of Newcastle disease virus
P.J. Miller, L.M. Kim, Hon S. Ip, C.L. Afonso
2009, Virology (391) 64-72
A comprehensive dataset of NDV genome sequences was evaluated using bioinformatics to characterize the evolutionary forces affecting NDV genomes. Despite evidence of recombination in most genes, only one event in the fusion gene of genotype V viruses produced evolutionarily viable progenies. The codon-associated rate of change for the six NDV...
Rock slope stability analysis along the North Carolina section of the Blue Ridge Parkway: Using a geographic information system (GIS) to integrate site data and digital geologic maps
R.S. Latham, R.M. Wooten, B.L. Cattanach, C.E. Merschat, G.N. Bozdog
2009, Conference Paper, 43rd U.S. Rock Mechanics Symposium and 4th U.S.-Canada Rock Mechanics Symposium
In 2008, the North Carolina Geological Survey (NCGS) completed a five-year geologic and geohazards inventory of the 406-km long North Carolina segment of the Blue Ridge Parkway (BRP). The ArcGIS™ format deliverables for rock slopes include a slope movement and slope movement deposit database and maps...
Predicting lesser scaup wetland use during spring migration in eastern South Dakota
S.N. Kahara, S. R. Chipps
2009, Great Plains Research (19) 157-167
The relative influence of physical, chemical, and biotic wetland characteristics on wetland use by spring migrating lesser scaup (Aythya affinis [Eyton]; hereafter "scaup") is not well understood. We compared characteristics of used and unused wetlands in eastern South Dakota. Used wetlands were larger (>2 ha; P = 0.05), with higher...
The use of local indicators of spatial association to improve LiDAR-derived predictions of potential amphibian breeding ponds
J.T. Julian, J.A. Young, J. W. Jones, C.D. Snyder, C. W. Wright
2009, Journal of Geographical Systems (11) 89-106
We examined whether spatially explicit information improved models that use LiDAR return signal intensity to discriminate in-pond habitat from terrestrial habitat at 24 amphibian breeding ponds. The addition of Local Indicators of Spatial Association (LISA) to LiDAR return intensity data significantly improved predictive models at all ponds, reduced residual error...
Short- and long-term response of deteriorating brackish marshes and open-water ponds to sediment enhancement by thin-layer dredge disposal
M.K. La Peyre, B. Gossman, Bryan P. Piazza
2009, Estuaries and Coasts (32) 390-402
Artificial sediment enhancement using a thin layer of dredged material has been suggested as a means to increase elevation and create soil conditions conducive to increased marsh structure and function in deteriorating marshes. Using a chronosequence approach, we examined the effects of sediment enhancement in deteriorating marsh and open-water pond...
A test and re-estimation of Taylor's empirical capacity-reserve relationship
K. R. Long
2009, Natural Resources Research (18) 57-63
In 1977, Taylor proposed a constant elasticity model relating capacity choice in mines to reserves. A test of this model using a very large (n = 1,195) dataset confirms its validity but obtains significantly different estimated values for the model coefficients. Capacity is somewhat inelastic with respect to reserves, with...
In-Flight performance of MESSENGER's Mercury dual imaging system
S.E. Hawkins, S.L. Murchie, K.J. Becker, C.M. Selby, F.S. Turner, M.W. Noble, N.L. Chabot, T.H. Choo, E.H. Darlington, B.W. Denevi, D.L. Domingue, C.M. Ernst, G.M. Holsclaw, N.R. Laslo, W.E. Mcclintock, L.M. Prockter, M.S. Robinson, S.C. Solomon, R.E. Sterner
2009, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The Mercury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 and planned for insertion into orbit around Mercury in 2011, has already completed two flybys of the innermost planet. The Mercury Dual Imaging System (MDIS) acquired nearly 2500 images from the first two flybys and viewed...
SSTL UK-DMC SLIM-6 data quality assessment
G. Chander, S. Saunier, M.J. Choate, P. L. Scaramuzza
2009, IEEE Transactions on Geoscience and Remote Sensing (47) 2380-2391
Satellite data from the Surrey Satellite Technology Limited (SSTL) United Kingdom (UK) Disaster Monitoring Constellation (DMC) were assessed for geometric and radiometric quality. The UK-DMC Surrey Linear Imager 6 (SLIM-6) sensor has a 32-m spatial resolution and a ground swath width of 640 km. The UK-DMC SLIM-6 design consists of...
