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...
Road zone effects in small-mammal communities
J.A. Bissonette, S.A. Rosa
2009, Ecology and Society (14)
Our study focused on the putative effects of roads on small-mammal communities in a high desert region of southern Utah. Specifically, we tested whether or not roads create adjacent zones characterized by lower small- mammal densities, abundance, and diversity. We sampled abundance of small mammals at increasing distances from Interstate...
Deformation of the Batestown till of the Lake Michigan lobe, Laurentide ice sheet
J.F. Thomason, N.R. Iverson
2009, Journal of Glaciology (55) 131-146
Deep, pervasive shear deformation of the bed to high strains (>100) may have been primarily responsible for flow and sediment transport of the Lake Michigan lobe of the Laurentide ice sheet. To test this hypothesis, we sampled at 0.2 m increments a basal till from one advance of the lobe...
Flood frequency analysis for nonstationary annual peak records in an urban drainage basin
G. Villarini, J. A. Smith, F. Serinaldi, J. Bales, P.D. Bates, W.F. Krajewski
2009, Advances in Water Resources (32) 1255-1266
Flood frequency analysis in urban watersheds is complicated by nonstationarities of annual peak records associated with land use change and evolving urban stormwater infrastructure. In this study, a framework for flood frequency analysis is developed based on the Generalized Additive Models for Location, Scale and Shape parameters (GAMLSS), a tool...
Gas chromatographic–mass spectrometric fragmentation study of phytoestrogens as their trimethylsilyl derivatives: Identification in soy milk and wastewater samples
Imma Ferrar, Larry B. Barber, E. Michael Thurman
2009, Journal of Chromatography A (1216) 6024-6032
An analytical method for the identification of eight plant phytoestrogens (biochanin A, coumestrol, daidzein, equol, formononetin, glycitein, genistein and prunetin) in soy products and wastewater samples was developed using gas chromatography coupled with ion trap mass spectrometry (GC/MS–MS). The phytoestrogens were derivatized as their trimethylsilyl ethers with trimethylchlorosilane (TMCS) and...
Integration of MODIS-derived metrics to assess interannual variability in snowpack, lake ice, and NDVI in southwest Alaska
Bradley C. Reed, Michael E. Budde, Page Spencer, Amy E. Miller
2009, Remote Sensing of Environment (113) 1443-1452
Impacts of global climate change are expected to result in greater variation in the seasonality of snowpack, lake ice, and vegetation dynamics in southwest Alaska. All have wide-reaching physical and biological ecosystem effects in the region. We used Moderate Resolution Imaging Spectroradiometer (MODIS) calibrated radiance, snow cover extent, and vegetation...
Gold and trace element zonation in pyrite using a laser imaging technique: Implications for the timing of gold in orogenic and carlin-style sediment-hosted deposits
R.R. Large, L. Danyushevsky, C. Hollit, V. Maslennikov, S. Meffre, S. Gilbert, S. Bull, R. Scott, P. Emsbo, H. Thomas, B. Singh, J. Foster
2009, Economic Geology (104) 635-668
Laser ablation ICP-MS imaging of gold and other trace elements in pyrite from four different sediment- hosted gold-arsenic deposits has revealed two distinct episodes of gold enrichment in each deposit: an early synsedimentary stage where invisible gold is concentrated in arsenian diagenetic pyrite along with other trace elements, in particular,...
Morphology of late Quaternary submarine landslides along the U.S. Atlantic continental margin
D.C. Twichell, J.D. Chaytor, Uri S. ten Brink, B. Buczkowski
2009, Marine Geology (264) 4-15
The nearly complete coverage of the U.S. Atlantic continental slope and rise by multibeam bathymetry and backscatter imagery provides an opportunity to reevaluate the distribution of submarine landslides along the margin and reassess the controls on their formation. Landslides can be divided into two categories based on their source areas:...
Fire behavior, weather, and burn severity of the 2007 anaktuvuk river tundra fire, North Slope, Alaska
Benjamin M. Jones, Crystal A. Kolden, Randi Jandt, John T. Abatzoglou, Frank Urban, Christopher D. Arp
2009, Arctic, Antarctic, and Alpine Research (41) 309-316
In 2007, the Anaktuvuk River Fire (ARF) became the largest recorded tundra fire on the North Slope of Alaska. The ARF burned for nearly three months, consuming more than 100,000 ha. At its peak in early September, the ARF burned at a rate of 7000 ha d-1. The conditions potentially...
Links between fluid circulation, temperature, and metamorphism in subducting slabs
G.A. Spinelli, K. Wang
2009, Geophysical Research Letters (36)
The location and timing of metamorphic reactions in subducting lithosph??re are influenced by thermal effects of fluid circulation in the ocean crust aquifer. Fluid circulation in subducting crust extracts heat from the Nankai subduction zone, causing the crust to pass through cooler metamorphic faci??s than if no fluid circulation occurs....
Distinguishing iron-reducing from sulfate-reducing conditions
F. H. Chapelle, P. M. Bradley, M.A. Thomas, P.B. McMahon
2009, Ground Water (47) 300-305
Ground water systems dominated by iron‐ or sulfate‐reducing conditions may be distinguished by observing concentrations of dissolved iron (Fe2+) and sulfide (sum of H2S, HS−, and S= species and denoted here as “H2S”). This approach is based on the observation that concentrations of Fe2+ and H2S in ground water systems tend to...
Decision making with epistemic uncertainty under safety constraints: An application to seismic design
D. Veneziano, A. Agarwal, E. Karaca
2009, Probabilistic Engineering Mechanics (24) 426-437
The problem of accounting for epistemic uncertainty in risk management decisions is conceptually straightforward, but is riddled with practical difficulties. Simple approximations are often used whereby future variations in epistemic uncertainty are ignored or worst-case scenarios are postulated. These strategies tend to produce sub-optimal decisions. We develop a general framework...
A model for the termination of the Ryukyu subduction zone against Taiwan: A junction of collision, subduction/separation, and subduction boundaries
F.T. Wu, W.-T. Liang, J.-C. Lee, H. Benz, A. Villasenor
2009, Journal of Geophysical Research B: Solid Earth (114)
The NW moving Philippine Sea plate (PSP) collides with the Eurasian plate (EUP) in the vicinity of Taiwan, and at the same time, it subducts toward the north along SW Ryukyu. The Ryukyu subduction zone terminates against eastern Taiwan. While the Ryukyu Trench is a linear bathym??trie low about 100...
Bacterial succession within an ephemeral hypereutrophic mojave desert playa lake
J.B. Navarro, D.P. Moser, A. Flores, C. Ross, Michael R. Rosen, H. Dong, G. Zhang, B.P. Hedlund
2009, Microbial Ecology (57) 307-320
Ephemerally wet playas are conspicuous features of arid landscapes worldwide; however, they have not been well studied as habitats for microorganisms. We tracked the geochemistry and microbial community in Silver Lake playa, California, over one flooding/desiccation cycle following the unusually wet winter of 2004-2005. Over the course of the study,...
Area sensitivity in North American grassland birds: Patterns and processes
C. A. Ribic, Rolf R. Koford, J.R. Herkert, Douglas H. Johnson, N.D. Niemuth, D.E. Naugle, Kristel K. Bakker, D. W. Sample, R.B. Renfrew
2009, The Auk (126) 233-244
Grassland birds have declined more than other bird groups in North America in the past 35-40 years (Vickery and Herkert 2001, Sauer et al. 2008), prompting a wide variety of research aimed at understanding these declines, as well as conservation programs trying to reverse the declines (Askins et al. 2007)....
Recent land cover history and nutrient retention in riparian wetlands
D.M. Hogan, M.R. Walbridge
2009, Environmental Management (44) 62-72
Wetland ecosystems are profoundly affected by altered nutrient and sediment loads received from anthropogenic activity in their surrounding watersheds. Our objective was to compare a gradient of agricultural and urban land cover history during the period from 1949 to 1997, with plant and soil nutrient concentrations in, and sediment deposition...
Spatial distribution and frequency of precipitation during an extreme event: July 2006 mesoscale convective complexes and floods in southeastern Arizona
Peter G. Griffiths, Christopher S. Magirl, Robert H. Webb, Erik Pytlak, Peter A. Troch, Steve W. Lyon
2009, Water Resources Research (45)
An extreme, multiday rainfall event over southeastern Arizona during 27–31 July 2006 caused record flooding and a historically unprecedented number of slope failures and debris flows in the Santa Catalina Mountains north of Tucson. An unusual synoptic weather pattern induced repeated nocturnal mesoscale convective systems over southeastern Arizona for five...
Influence of flow variability on floodplain formation and destruction, Little Missouri River, North Dakota
J.R. Miller, Jonathan M. Friedman
2009, Geological Society of America Bulletin (121) 752-759
Resolving observations of channel change into separate planimetric measurements of floodplain formation and destruction reveals distinct relations between these processes and the flow regime. We analyzed a time sequence of eight bottomland images from 1939 to 2003 along the Little Missouri River, North Dakota, to relate geomorphic floodplain change to...
Spatial and seasonal variations in mercury methylation and microbial community structure in a historic mercury mining area, Yolo County, California
J.M. Holloway, M. B. Goldhaber, K.M. Scow, R.E. Drenovsky
2009, Chemical Geology (267) 85-95
The relationships between soil parent lithology, nutrient concentrations, microbial biomass and community structure were evaluated in soils from a small watershed impacted by historic Hg mining. Upland and wetland soils, stream sediments and tailings were collected and analyzed for nutrients (DOC, SO4=, NO3-), Hg, MeHg, and phospholipid fatty acids (PLFA)....
The influence of microtopography on soil nutrients in created mitigation wetlands
K.F. Moser, C. Ahn, G.B. Noe
2009, Restoration Ecology (17) 641-651
This study explores the relationship between microtopography and soil nutrients (and trace elements), comparing results for created and reference wetlands in Virginia, and examining the effects of disking during wetland creation. Replicate multiscale tangentially conjoined circular transects were used to quantify microtopography both in terms of elevation and by two...
Size and elemental distributions of nano- to micro-particulates in the geochemically-stratified Great Salt Lake
X. Diaz, W.P. Johnson, D. Fernandez, D. L. Naftz
2009, Applied Geochemistry (24) 1653-1665
The characterization of trace elements in terms of their apportionment among dissolved, macromolecular, nano- and micro-particulate phases in the water column of the Great Salt Lake carries implications for the potential entry of toxins into the food web of the lake. Samples from the anoxic deep and oxic shallow brine...
Flowpath independent monitoring of reductive dechlorination potential in a fractured rock aquifer
P. M. Bradley, P.J. Lacombe, T.E. Imbrigiotta, F. H. Chapelle, D.J. Goode
2009, Ground Water Monitoring and Remediation (29) 46-55
The flowpath dependent approaches that are typically employed to assess biodegradation of chloroethene contaminants in unconsolidated aquifers are problematic in fractured rock settings, due to difficulties defining discrete groundwater flowpaths in such systems. In this study, the variation in the potential for chloroethene biodegradation with depth...
A regional-scale study of chromium and nickel in soils of northern California, USA
J.M. Morrison, M. B. Goldhaber, L. Lee, J.M. Holloway, R. B. Wanty, R.E. Wolf, J. F. Ranville
2009, Applied Geochemistry (24) 1500-1511
A soil geochemical survey was conducted in a 27,000-km2 study area of northern California that includes the Sierra Nevada Mountains, the Sacramento Valley, and the northern Coast Range. The results show that soil geochemistry in the Sacramento Valley is controlled primarily by the transport and weathering of parent material from...
Response of Sandhill Crane (Grus canadensis) riverine roosting habitat to changes in stage and sandbar morphology
P.J. Kinzel, J. M. Nelson, A.K. Heckman
2009, River Research and Applications (25) 135-152
Over the past century, flow regulation and vegetation encroachment have reduced active channel widths along the central Platte River, Nebraska. During the last two decades, an annual program of in-channel vegetation management has been implemented to stabilize or expand active channel widths. Vegetation management practices are intended to enhance riverine...
Monitoring forest changes in the southwestern United States using multitemporal Landsat data
James E. Vogelmann, Brian L. Tolk, Zhiliang Zhu
2009, Remote Sensing of Environment (113) 1739-1748
Landsat time series data sets were acquired for the Santa Fe National Forest in New Mexico. This area includes the San Pedro Parks Wilderness area, which was designated as an official wilderness in 1964. Eight autumnal Landsat Thematic Mapper (TM) scenes acquired from 1988 to 2006 were analyzed to determine...
