High-precision U-Pb geochronology in the Minnesota River Valley subprovince and its bearing on the Neoarchean to Paleoproterozoic evolution of the southern Superior Province
M.D. Schmitz, S. A. Bowring, D. L. Southwick, Terrence Boerboom, K.R. Wirth
2006, Geological Society of America Bulletin (118) 82-93
High-precision U-Pb ages have been obtained for high-grade gneisses, late-kinematic to postkinematic granitic plutons, and a crosscutting mafic dike of the Archean Minnesota River Valley tectonic subprovince, at the southern ramparts of the Superior craton of North America. The antiquity of the Minnesota River Valley terranes is confirmed by a...
Minding the gap: Frequency of indels in mtDNA control region sequence data and influence on population genetic analyses
John M. Pearce
2006, Molecular Ecology (15) 333-341
Insertions and deletions (indels) result in sequences of various lengths when homologous gene regions are compared among individuals or species. Although indels are typically phylogenetically informative, occurrence and incorporation of these characters as gaps in intraspecific population genetic data sets are rarely discussed. Moreover, the impact of gaps on estimates...
Shelf stratigraphy and the influence of antecedent substrate on Holocene reef development, south Oahu, Hawaii
E. E. Grossman, W. A. Barnhardt, P. Hart, B. M. Richmond, M.E. Field
2006, Marine Geology (226) 97-114
Paired analyses of drill cores and high-resolution seismic reflection data show that development of Holocene framework reefs on the Oahu (Hawaii) shelf is limited to settings of low wave energy and to the period 8000 to 3000 yr BP. A prominent bounding surface that is mapped across much of the...
Storage and interaction of compositionally heterogeneous magmas from the 1986 eruption of Augustine Volcano, Alaska
Diana C. Roman, Katharine V. Cashman, Cynthia A. Gardner, Paul J. Wallace, John J. Donovan
2006, Bulletin of Volcanology (68) 240-254
Compositional heterogeneity (56–64 wt% SiO2 whole-rock) in samples of tephra and lava from the 1986 eruption of Augustine Volcano, Alaska, raises questions about the physical nature of magma storage and interaction beneath this young and frequently active volcano. To determine conditions of magma storage and evolutionary histories of compositionally distinct magmas, we...
Albatross populations in peril: A population trajectory for Black-browed Albatrosses at South Georgia
J.M. Arnold, Solange Brault, J.P. Croxall
2006, Ecological Applications (16) 419-432
Simulation modeling was used to reconstruct Black-browed Albatross (Diomedea melanophris) population trends. Close approximations to observed data were accomplished by annually varying survival rates, reproductive success, and probabilities of returning to breed given success in previous years. The temporal shift in annual values coincided with the start of longline...
Determination of the platinum - Group elements (PGE) and gold (Au) in manganese nodule reference samples by nickel sulfide fire-assay and Te coprecipitation with ICP-MS
V. Balaram, R. Mathur, V.K. Banakar, J.R. Hein, C.R.M. Rao, Rao T. Gnaneswara, B. Dasaram
2006, Indian Journal of Marine Sciences (35) 7-16
Platinum group elements (PGE) and Au data in polymetallic oceanic ferromanganese nodule reference samples and crust samples obtained by inductively coupled plasma mass spectrometry (ICP-MS), after separation and pre-concentration by nickel sulfide fire-assay and Te coprecipitation, are presented. By optimizing several critical parameters such as flux composition, matrix matching calibration,...
Evaluation of methods to estimate lake herring spawner abundance in Lake Superior
D.L. Yule, J.D. Stockwell, G.A. Cholwek, L.M. Evrard, S. Schram, M. Seider, M. Symbal
2006, Transactions of the American Fisheries Society (135) 680-694
Historically, commercial fishers harvested Lake Superior lake herring Coregonus artedi for their flesh, but recently operators have targeted lake herring for roe. Because no surveys have estimated spawning female abundance, direct estimates of fishing mortality are lacking. The primary objective of this study was to determine the feasibility of using acoustic techniques...
Flow path oscillations in transient ground-water simulations of large peatland systems
A.S. Reeve, R. Evensen, P.H. Glaser, D. I. Siegel, D. Rosenberry
2006, Journal of Hydrology (316) 313-324
Transient numerical simulations of the Glacial Lake Agassiz Peatland near the Red Lakes in Northern Minnesota were constructed to evaluate observed reversals in vertical ground-water flow. Seasonal weather changes were introduced to a ground-water flow model by varying evapotranspiration and recharge over time. Vertical hydraulic reversals, driven by changes in...
Emerging concepts for management of river ecosystems and challenges to applied integration of physical and biological sciences in the Pacific Northwest, USA
Bruce Rieman, Jason B. Dunham, James Clayton
2006, International Journal of River Basin Management (4) 85-97
Integration of biological and physical concepts is necessary to understand and conserve the ecological integrity of river systems. Past attempts at integration have often focused at relatively small scales and on mechanistic models that may not capture the complexity of natural systems leaving substantial uncertainty about ecological responses to management...
Analysis of environmental variation in a Great Plains reservoir using principal components analysis and geographic information systems
J.M. Long, W.L. Fisher
2006, Lake and Reservoir Management (22) 132-140
We present a method for spatial interpretation of environmental variation in a reservoir that integrates principal components analysis (PCA) of environmental data with geographic information systems (GIS). To illustrate our method, we used data from a Great Plains reservoir (Skiatook Lake, Oklahoma) with longitudinal variation in physicochemical conditions. We measured...
Denitrification potential in stream sediments impacted by acid mine drainage: Effects of pH, various electron donors, and iron
J.L. Baeseman, R. L. Smith, J. Silverstein
2006, Microbial Ecology (51) 232-241
Acid mine drainage (AMD) contaminates thousands of kilometers of stream in the western United States. At the same time, nitrogen loading to many mountain watersheds is increasing because of atmospheric deposition of nitrate and increased human use. Relatively little is known about nitrogen cycling in acidic, heavy-metal-laden streams; however,...
A component-resampling approach for estimating probability distributions from small forecast ensembles
M. Dettinger
2006, Climatic Change (76) 149-168
In many meteorological and climatological modeling applications, the availability of ensembles of predictions containing very large numbers of members would substantially ease statistical analyses and validations. This study describes and demonstrates an objective approach for generating large ensembles of "additional" realizations from smaller ensembles, where the additional ensemble members share...
Fire clay
R.L. Virta
2006, Mining Engineering (58) 29-30
In 2005, six companies mined fire clay in Missouri, Ohio and South Carolina. Production was estimate to be 300 kt with a value of $8.3 million. Missouri was the leading producer state followed by Ohio and South Carolina. For the third consecutive year, sales and use of fire clays have...
Wildfires threaten mercury stocks in northern soils
M.R. Turetsky, J.W. Harden, H.R. Friedli, M. Flannigan, N. Payne, J. Crock, L. Radke
2006, Geophysical Research Letters (33)
With climate change rapidly affecting northern forests and wetlands, mercury reserves once protected in cold, wet soils are being exposed to burning, likely triggering large releases of mercury to the atmosphere. We quantify organic soil mercury stocks and burn areas across western, boreal Canada for use in fire emission models...
Observations in the Saturn system during approach and orbital insertion, with Cassini's visual and infrared mapping spectrometer (VIMS)
R. H. Brown, K. H. Baines, G. Bellucci, B. J. Buratti, F. Capaccioni, P. Cerroni, R. N. Clark, A. Coradini, D. P. Cruikshank, P. Drossart, V. Formisano, R. Jaumann, Y. Langevin, D. L. Matson, T. B. McCord, V. Mennella, R.M. Nelson, P. D. Nicholson, B. Sicardy, Christophe Sotin, N. Baugh, C.A. Griffith, G. B. Hansen, C. A. Hibbitts, T.W. Momary, M.R. Showalter
2006, Astronomy and Astrophysics (446) 707-716
The Visual and Infrared Mapping Spectrometer observed Phoebe, Iapetus, Titan and Saturn's rings during Cassini's approach and orbital insertion. Phoebe's surface contains water ice, CO2, and ferrous iron. lapetus contains CO2 and organic materials. Titan's atmosphere shows methane fluorescence, and night-side atmospheric emission that may be CO2 and CH3D. As...
Population structure of the giant garter snake, Thamnophis gigas
M.M. Paquin, G.D. Wylie, E.J. Routman
2006, Conservation Genetics (7) 25-36
The giant garter snake, Thamnophis gigas, is a threatened species endemic to California's Central Valley. We tested the hypothesis that current watershed boundaries have caused genetic differentiation among populations of T. gigas. We sampled 14 populations throughout the current geographic range of T. gigas and amplified 859 bp from the...
Borehole environmental tracers for evaluating net infiltration and recharge through desert bedrock
V.M. Heilweil, D. K. Solomon, P.M. Gardner
2006, Vadose Zone Journal (5) 98-102
Permeable bedrock aquifers in arid regions are being increasingly developed as water supplies, yet little is generally known about recharge processes and spatial and temporal variability. Environmental tracers from boreholes were used in this study to investigate net infiltration and recharge to the fractured Navajo Sandstone aquifer. Vadose zone tracer...
Dawning of Herpetological Conservation and Biology: A special welcome to your new journal
R. Bruce Bury, Malcolm L. McCallum, Stanley E. Trauth, Raymond A. Saumure
2006, Herpetological Conservation and Biology (1) i-iii
Inception of a new journal in herpetology is a rare event. The first discussion of developing a journal with an emphasis on natural history and conservation occurred among a subset of us (McCallum, others), while at the 2005 joint annual meeting of the SSAR/HL/ASIH in Tampa, Florida. Some of the...
Effects of enhanced zinc and copper in drinking water on spatial memory and fear conditioning
L.D. Chrosniak, L.N. Smith, C.G. McDonald, B.F. Jones, J.M. Flinn
2006, Journal of Geochemical Exploration (88) 91-94
Ingestion of enhanced zinc can cause memory impairments and copper deficiencies. This study examined the effect of zinc supplementation, with and without copper, on two types of memory. Rats raised pre- and post-natally on 10 mg/kg ZnCO3 or ZnSO4 in the drinking water were tested in a fear-conditioning experiment at...
Indirect food web interactions: Sea otters and kelp forest fishes in the Aleutian archipelago
S.E. Reisewitz, J. A. Estes, C.A. Simenstad
2006, Oecologia (146) 623-631
Although trophic cascades - the effect of apex predators on progressively lower trophic level species through top-down forcing - have been demonstrated in diverse ecosystems, the broader potential influences of trophic cascades on other species and ecosystem processes are not well studied. We used the overexploitation, recovery and subsequent collapse...
Methodology and results of calculating central California surface temperature trends: Evidence of human-induced climate change?
J.R. Christy, W.B. Norris, K. Redmond, K. P. Gallo
2006, Journal of Climate (19) 548-563
A procedure is described to construct time series of regional surface temperatures and is then applied to interior central California stations to test the hypothesis that century-scale trend differences between irrigated and nonirrigated regions may be identified. The procedure requires documentation of every point in time at which a discontinuity...
Identification and regulatory analysis of rainbow trout tapasin and tapasin-related genes
E.D. Landis, Y. Palti, J. Dekoning, R. Drew, R.B. Phillips, J.D. Hansen
2006, Immunogenetics (58) 56-69
Tapasin (TAPBP) is a key member of MHC class Ia antigen-loading complexes, bridging the class Ia molecule to the transporter associated with antigen presentation (TAP). As part of an ongoing study of MHC genomics in rainbow trout, we have identified two rainbow trout TAPBP genes (Onmy-TAPBP.a and .b) and a...
Concurrent assessment of fish and habitat in warmwater streams in Wyoming
M.C. Quist, W.A. Hubert, F.J. Rahel
2006, Fisheries Management and Ecology (13) 9-20
Fisheries research and management in North America have focused largely on sport fishes, but native non-game fishes have attracted increased attention due to their declines. The Warmwater Stream Assessment (WSA) was developed to evaluate simultaneously both fish and habitat in Wyoming streams by a process that includes three major components:...
Site-specific effects on productivity of an upper trophic-level marine predator: Bottom-up, top-down, and mismatch effects on reproduction in a colonial seabird
R.M. Suryan, D.B. Irons, E.D. Brown, P.G.R. Jodice, D.D. Roby
2006, Progress in Oceanography (68) 303-328
We investigated the relative roles of bottom-up and top-down factors in limiting productivity of an upper trophic level marine predator. Our primary working hypothesis was that the reproductive success of black-legged kittiwakes (Rissa tridactyla) a piscivorous, colonial-nesting seabird, was most limited by the abundance, distribution, and species composition of surface-schooling...
Land-use effects on erosion, sediment yields, and reservoir sedimentation: A case study in the Lago Loiza Basin, Puerto Rico
Allen C. Gellis, Richard M. T. Webb, S. C. McIntyre, William J. Wolfe
2006, Physical Geography (27) 39-69
Lago Loíza impounded in 1953 to supply San Juan, Puerto Rico, with drinking water; by 1994, it had lost 47% of its capacity. To characterize sedimentation in Lago Loíza, a study combining land-use history, hillslope erosion rates, and subbasin sediment yields was conducted. Sedimentation rates during the early part of...
