Temperature mediated moose survival in Northeastern Minnesota
M.S. Lenarz, M.E. Nelson, M.W. Schrage, A.J. Edwards
2009, Journal of Wildlife Management (73) 503-510
The earth is in the midst of a pronounced warming trend and temperatures in Minnesota, USA, as elsewhere, are projected to increase. Northern Minnesota represents the southern edge to the circumpolar distribution of moose (Alces alces), a species intolerant of heat. Moose increase their metabolic rate to regulate their core...
Factors affecting the age-C resident fish community along shorelines of the Hanford Reach of the Columbia River
D.M. Gadomski, P.G. Wagner
2009, Northwest Science (83) 180-188
The Hanford Reach is one of the few remaining unimpounded sections of the Columbia River. However, because of flow management at upstream dams, there are often large fluctuations in water level. To determine how environmental conditions might affect age-0 resident fishes in the Hanford Reach, we evaluated species composition, distribution,...
Geophysical investigation of seamounts near the Ogasawara fracture zone, western Pacific
T.-G. Lee, Kenneth Lee, J.R. Hein, J.-W. Moon
2009, Earth, Planets and Space (61) 319-331
This paper provides an analysis of multi-channel seismic data obtained during 2000-2001 on seamounts near the Ogasawara Fracture Zone (OFZ) northwest of the Marshall Islands in the western Pacific. The OFZ is unique in that it is a wide rift zone that includes many seamounts. Seven units are delineated on...
A less field-intensive robust design for estimating demographic parameters with Mark-resight data
B.T. McClintock, Gary C. White
2009, Ecology (90) 313-320
The robust design has become popular among animal ecologists as a means for estimating population abundance and related demographic parameters with mark-recapture data. However, two drawbacks of traditional mark-recapture are financial cost and repeated disturbance to animals. Mark-resight methodology may in many circumstances be a less expensive and less invasive...
Use of OSL dating to establish the stratigraphic framework of Quaternary eolian sediments, Anton scarp upper trench, Northeastern Colorado High Plains, USA
S. A. Mahan, D.C. Noe, J.P. McCalpin
2009, Quaternary International (199) 92-103
This paper contains the results of the optically stimulated luminescence (OSL) dating used to establish stratigraphic ages and relationships of eolian sediments in a trench in northeastern Colorado, USA. This trench was located in the upper face of the Anton scarp, a major topographic lineament trending NW-SE for a distance...
Constraints on deep moonquake focal mechanisms through analyses of tidal stress
R.C. Weber, B.G. Bills, C.L. Johnson
2009, Journal of Geophysical Research E: Planets (114)
[1] A relationship between deep moonquake occurrence and tidal forcing is suggested by the monthly periodicities observed in the occurrence times of events recorded by the Apollo Passive Seismic Experiment. In addition, the typically large S wave to P wave arrival amplitude ratios observed on deep moonquake seismograms are indicative...
Scientific communications: Re-Os sulfide (bornite, chalcopyrite, and pyrite) systematics of the carbonate-hosted copper deposits at ruby creek, southern brooks range, Alaska
D. Selby, K.D. Kelley, M.W. Hitzman, J. Zieg
2009, Economic Geology (104) 437-444
New Re-Os data for chalcopyrite, bornite, and pyrite from the carbonate-hosted Cu deposit at Ruby Creek (Bornite), Alaska, show extremely high Re abundances (hundreds of ppb, low ppm) and contain essentially no common Os. The Re-Os data provide the first absolute ages of ore formation for the carbonate-hosted Ruby Creek...
Delayed tree mortality in the Atchafalaya Basin of Southern Louisiana following Hurricane Andrew
B. D. Keeland, L.E. Gorham
2009, Wetlands (29) 101-111
Hurricanes can damage trees in forested wetlands, and the potential for mortality related to these storms exists due to the effects of tree damage over time. In August 1992, Hurricane Andrew passed through the forested wetlands of southern Louisiana with winds in excess of 225 kph. Although more than 78...
Reducing streamflow forecast uncertainty: Application and qualitative assessment of the upper klamath river Basin, Oregon
L.E. Hay, G.J. McCabe, M.P. Clark, J. C. Risley
2009, Journal of the American Water Resources Association (45) 580-596
The accuracy of streamflow forecasts depends on the uncertainty associated with future weather and the accuracy of the hydrologic model that is used to produce the forecasts. We present a method for streamflow forecasting where hydrologic model parameters are selected based on the climate state. Parameter sets for a hydrologic...
Desmograptus. micronematodes, a silurian dendroid graptolite, and its ultrastructure
K.M. Saunders, D.E.B. Bates, Joanne Kluessendorf, David K. Loydell, Donald G. Mikulic
2009, Palaeontology (52) 541-559
Desmograptus micronematodes from Thornton quarry, Cook County, Illinois, USA, remarkably preserved in relief and encased in pyrite, is described. The internal details of the thecae, and of the stolon system, examined using the SEM, allow the reconstruction of the growth of a stipe. The stolons and stolonal nodes are formed...
Groundwater quality impacts from the land application of treated municipal wastewater in a large karstic spring basin: Chemical and microbiological indicators
B. G. Katz, Dale W. Griffin, J.H. Davis
2009, Science of the Total Environment (407) 2872-2886
Geochemical and microbiological techniques were used to assess water-quality impacts from the land application of treated municipal wastewater in the karstic Wakulla Springs basin in northern Florida. Nitrate-N concentrations have increased from about 0.2 to as high as 1.1??mg/L (milligrams per liter) during the past 30??years in Wakulla Springs, a...
Wolf, Canis lupus, visits to white-tailed deer, Odocoileus virginianus, summer ranges: Optimal foraging?
D. J. Demma, L.D. Mech
2009, Canadian Field-Naturalist (123) 299-303
We tested whether Wolf (Canis lupus) visits to individual female White-tailed Deer (Odocoileus virginianus) summer ranges during 2003 and 2004 in northeastern Minnesota were in accord with optimal-foraging theory. Using GPS collars with 10- to 30-minute location attempts on four Wolves and five female deer, plus eleven VHF-collared female deer...
Genetic structure of lake whitefish (Coregonus clupeaformis) in Lake Michigan
J.A. VanDeHey, Brian L. Sloss, Paul J. Peeters, T.M. Sutton
2009, Canadian Journal of Fisheries and Aquatic Sciences (66) 382-393
Genetic relationships among lake whitefish (Coregonus clupeaformis) spawning aggregates in Lake Michigan were assessed and used to predict a stock or management unit (MU) model for the resource. We hypothesized that distinct spawning aggregates represented potential MUs and that differences at molecular markers underlie population differentiation. Genetic stock identification using...
Evaluating abundance estimate precision and the assumptions of a count-based index for small mammals
A.S. Wiewel, A.A.Y. Adams, G.H. Rodda
2009, Journal of Wildlife Management (73) 761-771
Conservation and management of small mammals requires reliable knowledge of population size. We investigated precision of markrecapture and removal abundance estimates generated from live-trapping and snap-trapping data collected at sites on Guam (n 7), Rota (n 4), Saipan (n 5), and Tinian (n 3), in the Mariana Islands. We also...
Comparing stochastic point-source and finite-source ground-motion simulations: SMSIM and EXSIM
D.M. Boore
2009, Bulletin of the Seismological Society of America (99) 3202-3216
Comparisons of ground motions from two widely used point-source and finite-source ground-motion simulation programs (SMSIM and EXSIM) show that the following simple modifications in EXSIM will produce agreement in the motions from a small earthquake at a large distance for the two programs: (1) base the scaling of high frequencies...
Analysis of methods to estimate spring flows in a karst aquifer
N. Sepulveda
2009, Ground Water (47) 337-349
Hydraulically and statistically based methods were analyzed to identify the most reliable method to predict spring flows in a karst aquifer. Measured water levels at nearby observation wells, measured spring pool altitudes, and the distance between observation wells and the spring pool were the parameters used to match measured spring...
Symbiotic regulation of plant growth, development and reproduction
R. J. Rodriguez, D. Carl Freeman, E.D. McArthur, Y.-O. Kim, R. S. Redman
2009, Communitative and Integrative Biology (2) 141-143
The growth and development of rice (Oryzae sativa) seedlings was shown to be regulated epigenetically by a fungal endophyte. In contrast to un-inoculated (nonsymbiotic) plants, endophyte colonized (symbiotic) plants preferentially allocated resources into root growth until root hairs were well established. During that time symbiotic roots expanded at five times...
Natural resource assessment: an approach to science based planning in national parks
C.G. Mahan, J.P. Vanderhorst, J.A. Young
2009, Environmental Management (43) 1301-1312
We conducted a natural resource assessment at two national parks, New River Gorge National River and Shenandoah National Park, to help meet the goals of the Natural Resource Challenge-a program to help strengthen natural resource management at national parks. We met this challenge by synthesizing and interpreting natural resource information...
Response of the everglades ridge and slough landscape to climate variability and 20th-century water management
C.E. Bernhardt, Debra A. Willard
2009, Ecological Applications (19) 1723-1738
The ridge and slough landscape of the Florida Everglades consists of a mosaic of linear sawgrass ridges separated by deeper-water sloughs with tree islands interspersed throughout the landscape. We used pollen assemblages from transects of sediment cores spanning sawgrass ridges, sloughs, and ridge-slough transition zones to determine the timing of...
Interactive effects of fire, soil climate, and moss on CO2 fluxes in black spruce ecosystems of interior Alaska
J. A. O'Donnell, M.R. Turetsky, J.W. Harden, K.L. Manies, L.E. Pruett, G. Shetler, J. C. Neff
2009, Ecosystems (12) 57-72
Fire is an important control on the carbon (C) balance of the boreal forest region. Here, we present findings from two complementary studies that examine how fire modifies soil organic matter properties, and how these modifications influence rates of decomposition and C exchange in black spruce (Picea mariana) ecosystems of...
Nicotine, acetanilide and urea multi-level2H-,13C- and15N-abundance reference materials for continuous-flow isotope ratio mass spectrometry
A. Schimmelmann, A. Albertino, P.E. Sauer, H. Qi, R. Molinie, F. Mesnard
2009, Rapid Communications in Mass Spectrometry (23) 3513-3521
Accurate determinations of stable isotope ratios require a calibration using at least two reference materials with different isotopic compositions to anchor the isotopic scale and compensate for differences in machine slope. Ideally, the S values of these reference materials should bracket the isotopic range of samples with unknown S values....
Using nitrate dual isotopic composition (δ15N and δ18O) as a tool for exploring sources and cycling of nitrate in an estuarine system: Elkhorn Slough, California
Scott D. Wankel, Carol Kendall, Adina Paytan
2009, Journal of Geophysical Research G: Biogeosciences (114)
Nitrate (NO3−) concentrations and dual isotopic composition (δ15N and δ18O) were measured during various seasons and tidal conditions in Elkhorn Slough to evaluate mixing of sources of NO3− within this California estuary. We found the isotopic composition of NO3− was influenced most heavily by mixing of two primary sources with unique isotopic signatures,...
Isotopic variability of mercury in ore, mine-waste calcine, and leachates of mine-waste calcine from areas mined for mercury
S.J. Stetson, J. E. Gray, R. B. Wanty, D.L. Macalady
2009, Environmental Science & Technology (43) 7331-7336
The isotopic composition of mercury (Hg) was determined in cinnabar ore, mine-waste calcine (retorted ore), and leachates obtained from water leaching experiments of calcine from two large Hg mining districts in the U.S. This study is the first to report significant mass-dependent Hg isotopic fractionation between cinnabar ore and resultant...
Sediment storage and transport in Pancho Rico Valley during and after the Pleistocene-Holocene transition, Coast Ranges of central California (Monterey County)
A.F. Garcia, S. A. Mahan
2009, Earth Surface Processes and Landforms (34) 1136-1150
Factors influencing sediment transport and storage within the 156??6 km2 drainage basin of Pancho Rico Creek (PRC), and sediment transport from the PRC drainage basin to its c. 11000 km2 mainstem drainage (Salinas River) are investigated. Numeric age estimates are determined by optically stimulated luminescence (OSL) dating on quartz grains...
The effect of moisture content on the thermal conductivity of moss and organic soil horizons from black spruce ecosystems in interior alaska
J. A. O'Donnell, V.E. Romanovsky, J.W. Harden, A. D. McGuire
2009, Soil Science (174) 646-651
Organic soil horizons function as important controls on the thermal state of near-surface soil and permafrost in high-latitude ecosystems. The thermal conductivity of organic horizons is typically lower than mineral soils and is closely linked to moisture content, bulk density, and water phase. In this study, we examined the relationship...
