Recent paleorecords document rising mercury contamination in Lake Tanganyika
Christopher H. Conaway, Peter W. Swarzenski, A.S. Cohen
2012, Applied Geochemistry (27) 352-359
Recent Lake Tanganyika Hg deposition records were derived using 14C and excess 210Pb geochronometers in sediment cores collected from two contrasting depositional environments: the Kalya Platform, located mid-lake and more removed from watershed impacts, and the Nyasanga/Kahama River delta region, located close to the lake’s shoreline north of Kigoma. At the Kalya...
Beach response dynamics of a littoral cell using a 17-year single-point time series of sand thickness
Patrick L. Barnard, D.M. Hubbard, J.E. Dugan
2012, Geomorphology (139-140) 588-598
A 17-year time series of near-daily sand thickness measurements at a single intertidal location was compared with 5 years of semi-annual 3-dimensional beach surveys at the same beach, and at two other beaches within the same littoral cell. The daily single point measurements correlated extremely well with the mean beach elevation...
On valuing patches: Estimating contributions to metapopulation growth with reverse-time capture-recapture modelling
J.S. Sanderlin, P.M. Waser, J.E. Hines, J.D. Nichols
2012, Proceedings of the Royal Society B: Biological Sciences (279) 480-488
Metapopulation ecology has historically been rich in theory, yet analytical approaches for inferring demographic relationships among local populations have been few. We show how reverse-time multi-state capture–recapture models can be used to estimate the importance of local recruitment and interpopulation dispersal to metapopulation growth. We use ‘contribution metrics’ to infer...
Incidence of adult brain cancers is higher in countries where the protozoan parasite Toxoplasma gondii is common
Frederic Thomas, Kevin D. Lafferty, Jacques Brodeur, Eric Elguero, Michel Gauthier-Clerc, Dorothee Misse
2012, Biology Letters (8) 101-103
We explored associations between the common protozoan parasite Toxoplasma gondii and brain cancers in human populations. We predicted that T. gondii could increase the risk of brain cancer because it is a long-lived parasite that encysts in the brain, where it provokes inflammation and inhibits apoptosis. We used a medical...
Field experiment provides ground truth for surface nuclear magnetic resonance measurement
R. Knight, E. Grunewald, T. Irons, K. Dlubac, Y. Song, H.N. Bachman, B. Grau, D. Walsh, J.D. Abraham, J. Cannia
2012, Geophysical Research Letters (39) 1-7
The need for sustainable management of fresh water resources is one of the great challenges of the 21st century. Since most of the planet's liquid fresh water exists as groundwater, it is essential to develop non-invasive geophysical techniques to characterize groundwater aquifers. A field experiment was conducted in the High...
Empirical methods for detecting regional trends and other spatial expressions in antrim shale gas productivity, with implications for improving resource projections using local nonparametric estimation techniques
Timothy C. Coburn, Philip A. Freeman, Emil D. Attanasi
2012, Natural Resources Research (21) 1-21
The primary objectives of this research were to (1) investigate empirical methods for establishing regional trends in unconventional gas resources as exhibited by historical production data and (2) determine whether or not incorporating additional knowledge of a regional trend in a suite of previously established local nonparametric resource prediction algorithms...
Surface heat flow and CO2 emissions within the Ohaaki hydrothermal field, Taupo Volcanic Zone, New Zealand
C. Rissmann, B. Christenson, Cynthia A. Werner, M. Leybourne, J. Cole, D. Gravley
2012, Applied Geochemistry (27) 223-239
Carbon dioxide emissions and heat flow have been determined from the Ohaaki hydrothermal field, Taupo Volcanic Zone (TVZ), New Zealand following 20 a of production (116 MWe). Soil CO2 degassing was quantified with 2663 CO2 flux measurements using the accumulation chamber method, and 2563 soil temperatures were measured and converted to equivalent heat flow...
Occurrence and geochemistry of radium in water from principal drinking-water aquifer systems of the United States
Z. Szabo, Vincent T. DePaul, J.M. Fischer, T. F. Kraemer, E. Jacobsen
2012, Applied Geochemistry (27) 729-752
A total of 1270 raw-water samples (before treatment) were collected from 15 principal and other major aquifer systems (PAs) used for drinking water in 45 states in all major physiographic provinces of the USA and analyzed for concentrations of the Ra isotopes 224Ra, 226Ra and 228Ra establishing...
Climatic forcing of Quaternary deep-sea benthic communities in the North Pacific Ocean
Moriaki Yasuhara, G. Hunt, T. M. Cronin, N. Hokanishi, H. Kawahata, Akira Tsujimoto, M. Ishitake
2012, Paleobiology (38) 162-179
There is growing evidence that changes in deep-sea benthic ecosystems are modulated by climate changes, but most evidence to date comes from the North Atlantic Ocean. Here we analyze new ostracod and published foraminiferal records for the last 250,000 years on Shatsky Rise in the North Pacific Ocean. Using linear...
Verifiable metamodels for nitrate losses to drains and groundwater in the Corn Belt, USA
Bernard T. Nolan, Robert W. Malone, Jo Ann M. Gronberg, K.R. Thorp, Liwang Ma
2012, Environmental Science & Technology (46) 901-908
Nitrate leaching in the unsaturated zone poses a risk to groundwater, whereas nitrate in tile drainage is conveyed directly to streams. We developed metamodels (MMs) consisting of artificial neural networks to simplify and upscale mechanistic fate and transport models for prediction of nitrate losses by drains and leaching in the...
Updated determination of stress parameters for nine well-recorded earthquakes in eastern North America
David M. Boore
2012, Seismological Research Letters (83) 190-199
Stress parameters (Δσ) are determined for nine relatively well-recorded earthquakes in eastern North America for ten attenuation models. This is an update of a previous study by Boore et al. (2010). New to this paper are observations from the 2010 Val des Bois earthquake, additional observations for the 1988 Saguenay and 2005...
Wolf population dynamics in the U.S. Northern Rocky Mountains are affected by recruitment and human-caused mortality
J.A. Gude, M.S. Mitchell, Robin E. Russell, C.A. Sime, E.E. Bangs, L.D. Mech, R.R. Ream
2012, Journal of Wildlife Management (76) 108-118
Reliable analyses can help wildlife managers make good decisions, which are particularly critical for controversial decisions such as wolf (Canis lupus) harvest. Creel and Rotella (2010) recently predicted substantial population declines in Montana wolf populations due to harvest, in contrast to predictions made by Montana Fish, Wildlife and Parks (MFWP)....
Population fragmentation and inter-ecosystem movements of grizzly bears in Western Canada and the Northern United States
M.F. Proctor, David Paetkau, B. N. McLellan, G.B. Stenhouse, K.C. Kendall, R.D. Mace, W.F. Kasworm, C. Servheen, C.L. Lausen, M.L. Gibeau, W.L. Wakkinen, M.A. Haroldson, G. Mowat, C.D. Apps, L.M. Ciarniello, R.M.R. Barclay, M.S. Boyce, C.C. Schwartz, C. Strobeck
2012, Wildlife Monographs 1-46
Population fragmentation compromises population viability, reduces a species ability to respond to climate change, and ultimately may reduce biodiversity. We studied the current state and potential causes of fragmentation in grizzly bears over approximately 1,000,000 km 2 of western Canada, the northern United States (US), and southeast Alaska. We...
Exploring mechanisms underlying sex-specific differences in mortality of Lake Michigan bloaters
D.B. Bunnell, C.P. Madenjian, M.W. Rogers, J.D. Holuszko, L.J. Begnoche
2012, Transactions of the American Fisheries Society (141) 204-214
Sex-specific differences in mortality rates have been observed among freshwater and marine fish taxa, and underlying mechanisms can include sex-specific differences in (1) age at maturity, (2) growth rate, or (3) activity or behavior during the spawning period. We used a long-term (1973–2009) Lake Michigan data set to evaluate whether...
Photodissolution of soil organic matter
L.M. Mayer, K.R. Thornton, L.L. Schick, J.D. Jastrow, Jennifer W. Harden
2012, Geoderma (170) 314-321
Sunlight has been shown to enhance loss of organic matter from aquatic sediments and terrestrial plant litter, so we tested for similar reactions in mineral soil horizons. Losses of up to a third of particulate organic carbon occurred after continuous exposure to full-strength sunlight for dozens of hours, with similar...
Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments
A.D. Rooney, D. Selby, M. D. Lewan, P. G. Lillis, J.-P. Houzay
2012, Geochimica et Cosmochimica Acta (77) 275-291
Successful application of the 187Re–187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products...
Landscape controls on the timing of spring, autumn, and growing season length in mid-Atlantic forests
A.J. Elmore, S.M. Guinn, B. J. Minsley, A.D. Richardson
2012, Global Change Biology (18) 656-674
The timing of spring leaf development, trajectories of summer leaf area, and the timing of autumn senescence have profound impacts to the water, carbon, and energy balance of ecosystems, and are likely influenced by global climate change. Limited field-based and remote-sensing observations have suggested complex spatial patterns related to geographic...
Experimental determination of soil heat storage for the simulation of heat transport in a coastal wetland
Michael Swain, Matthew Swain, Melinda Lohmann, Eric Swain
2012, Journal of Hydrology (422-423) 53-62
Two physical experiments were developed to better define the thermal interaction of wetland water and the underlying soil layer. This information is important to numerical models of flow and heat transport that have been developed to support biological studies in the South Florida coastal wetland areas. The experimental apparatus...
Histologic, immunologic and endocrine biomarkers indicate contaminant effects in fishes of the Ashtabula River
L. R. Iwanowicz, V. S. Blazer, N.P. Hitt, S. D. McCormick, D.S. Devault, C. A. Ottinger
2012, Ecotoxicology (21) 165-182
The use of fish as sentinels of aquatic ecosystem health is a biologically relevant approach to environmental monitoring and assessment. We examined the health of the Ashtabula River using histologic, immunologic, and endocrine biomarkers in brown bullhead (BB; Ameiurus nebulosus) and largemouth bass (Micropterus salmoides) and compared fish collected from...
Reducing uncertainty about objective functions in adaptive management
Byron K. Williams
2012, Ecological Modelling (225) 61-65
This paper extends the uncertainty framework of adaptive management to include uncertainty about the objectives to be used in guiding decisions. Adaptive decision making typically assumes explicit and agreed-upon objectives for management, but allows for uncertainty as to the structure of the decision process that generates change through time. Yet...
Ocean-atmosphere dynamics during Hurricane Ida and Nor'Ida: An application of the coupled ocean-atmosphere-wave-sediment transport (COAWST) modeling system
Maitane Olabarrieta, John C. Warner, Brandy N. Armstrong, Joseph B. Zambon, Ruoying He
2012, Ocean Modelling (43-44) 112-137
The coupled ocean–atmosphere–wave–sediment transport (COAWST) modeling system was used to investigate atmosphere–ocean–wave interactions in November 2009 during Hurricane Ida and its subsequent evolution to Nor’Ida, which was one of the most costly storm systems of the past two decades. One interesting aspect of this...
Application of a weighted-averaging method for determining paleosalinity: a tool for restoration of south Florida's estuaries
G.L. Wingard, J.W. Hudley
2012, Estuaries and Coasts (35) 262-280
A molluscan analogue dataset is presented in conjunction with a weighted-averaging technique as a tool for estimating past salinity patterns in south Florida’s estuaries and developing targets for restoration based on these reconstructions. The method, here referred to as cumulative weighted percent (CWP), was tested using modern surficial samples collected...
Foraging segregation and genetic divergence between geographically proximate colonies of a highly mobile seabird
Anne E. Wiley, Andreanna J. Welch, P.H. Ostrom, Helen F. James, Craig A. Stricker, R.C. Fleischer, H. Gandhi, Josh Adams, D. G. Ainley, F. Duvall, N. Holmes, D. Hu, S. Judge, J. Penniman, K.A. Swindle
2012, Oecologia (168) 119-130
Foraging segregation may play an important role in the maintenance of animal diversity, and is a proposed mechanism for promoting genetic divergence within seabird species. However, little information exists regarding its presence among seabird populations. We investigated genetic and foraging divergence between two colonies of endangered Hawaiian petrels (Pterodroma sandwichensis)...
Regional scale impacts of Tamarix leaf beetles (Diorhabda carinulata) on the water availability of western U.S. rivers as determined by multi-scale remote sensing methods
Pamela L. Nagler, Tim Brown, Kevin R. Hultine, Charles van Riper III, Daniel W. Bean, Philip E. Dennison, R. Scott Murray, Edward P. Glenn
2012, Remote Sensing of Environment (118) 227-240
Tamarix leaf beetles (Diorhabda carinulata) have been widely released on western U.S. rivers to control introduced shrubs in the genus Tamarix. Part of the motivation to control Tamarix is to salvage water for human use. Information is needed on the impact of beetles on Tamarix seasonal leaf production and subsequent...
Ecoregional analysis of nearshore sea-surface temperature in the North Pacific
M.C. Payne, C.A. Brown, D.A. Reusser, H. Lee II
2012, PLoS ONE (7)
The quantification and description of sea surface temperature (SST) is critically important because it can influence the distribution, migration, and invasion of marine species; furthermore, SSTs are expected to be affected by climate change. To better understand present temperature regimes, we assembled a 29-year nearshore time series of...
