Conceptual model of sedimentation in the Sacramento-San Joaquin River Delta
David H. Schoellhamer, Scott Wright, Judith Z. Drexler
2012, San Francisco Estuary and Watershed Science (10)
Sedimentation in the Sacramento–San Joaquin River Delta builds the Delta landscape, creates benthic and pelagic habitat, and transports sediment-associated contaminants. Here we present a conceptual model of sedimentation that includes submodels for river supply from the watershed to the Delta, regional transport within the Delta and seaward exchange, and local...
Exceptional warming in the Western Pacific-Indian Ocean warm pool has contributed to more frequent droughts in eastern Africa
Christopher C. Funk
Thomas C. Peterson, Peter A. Stott, Stephanie Herring, editor(s)
2012, Bulletin of the American Meteorological Society (93) 1049-1051
In 2011, East Africa faced a tragic food crisis that led to famine conditions in parts of Somalia and severe food shortages in parts of Ethiopia and Somalia. While many nonclimatic factors contributed to this crisis (high global food prices, political instability, and chronic poverty, among others) failed rains in...
A horizon scanning assessment of current and potential future threats to migratory shorebirds
William J. Sutherland, José A. Alves, Tatsuya Amano, Charlotte H. Chang, Nicholas C. Davidson, C. Max Finlayson, Jennifer A. Gill, Robert E. Gill Jr., Patricia M. González, Tomas Gretar Gunnarsson, David Kleijn, Chris J. Spray, Tamás Székely, Des B.A. Thompson
2012, Ibis (154) 663-679
We review the conservation issues facing migratory shorebird populations that breed in temperate regions and use wetlands in the non-breeding season. Shorebirds are excellent model organisms for understanding ecological, behavioural and evolutionary processes and are often used as indicators of wetland health. A global team of experienced shorebird researchers identified...
Dwarf char, a new form of chars (the genus Salvelinus) in Lake Kronotskoe
S.D. Pavlov, E.A. Pivovarov, Carl O. Ostberg
2012, Doklady Biological Sciences (442) 20-23
Lake Kronotskoe is situated in the Kronotskii State Nature Reserve and is a unique natural heritage of Kamchatka. The lake–river system of the reserve includes numerous springs and small streams and three large inflowing rivers, Listvennichnaya, Unana, and Uzon, which form the main bays of...
Temporal evolution of stable water isotopologues in cloud droplets in a hill cap cloud in central Europe (HCCT-2010)
J.K. Spiegel, F. Aemisegger, M. Scholl, F.G. Wienhold, J.L. Collett Jr., T. Lee, D. van Pinxteren, S. Mertes, A. Tilgner, H. Herrmann, Roland A. Werner, N. Buchmann, W. Eugster
2012, Atmospheric Chemistry and Physics (12) 11679-11694
In this work, we present the first study resolving the temporal evolution of δ2H and δ18O values in cloud droplets during 13 different cloud events. The cloud events were probed on a 937 m high mountain chain in Germany in the framework of the Hill Cap Cloud Thuringia 2010 campaign...
Deep Arctic Ocean warming during the last glacial cycle
T. M. Cronin, G. S. Dwyer, J. Farmer, H.A. Bauch, R.F. Spielhagen, M. Jakobsson, J. Nilsson, W. M. Briggs Jr., A. Stepanova
2012, Nature Geoscience (5) 631-634
In the Arctic Ocean, the cold and relatively fresh water beneath the sea ice is separated from the underlying warmer and saltier Atlantic Layer by a halocline. Ongoing sea ice loss and warming in the Arctic Ocean have demonstrated the instability of the halocline, with implications for further sea ice...
Drainage network structure and hydrologic behavior of three lake-rich watersheds on the Arctic Coastal Plain, Alaska
C.D. Arp, M.S. Whitman, Benjamin M. Jones, R. Kemnitz, G. Grosse, F.E. Urban
2012, Arctic, Antarctic, and Alpine Research (44) 385-394
Watersheds draining the Arctic Coastal Plain (ACP) of Alaska are dominated by permafrost and snowmelt runoff that create abundant surface storage in the form of lakes, wetlands, and beaded streams. These surface water elements compose complex drainage networks that affect aquatic ecosystem connectivity and hydrologic behavior. The 4676 km2 Fish...
Current and potential sustainable corn stover feedstock for biofuel production in the United States
Zhengxi Tan, Shu-Guang Liu, Larry L. Tieszen, Norman Bliss
2012, Biomass and Bioenergy (47) 372-386
Increased demand for corn (Zea mays L.) stover as a feedstock for cellulosic ethanol raises concerns about agricultural sustainability. Excessive corn stover harvesting could have long-term impacts on soil quality. We estimated current and future stover production and evaluated the potential harvestable stover amount (HSA) that could be used for biofuel...
A perspective on modern pesticides, pelagic fish declines, and unknown ecological resilience in highly managed ecosystems
Nathaniel L. Scholz, Erica Fleishman, Larry Brown, Inge Werner, Michael L. Johnson, Marjorie L. Brooks, Carys L. Mitchelmore, Daniel Schlenk
2012, BioScience (62) 428-434
Pesticides applied on land are commonly transported by runoff or spray drift to aquatic ecosystems, where they are potentially toxic to fishes and other nontarget organisms. Pesticides add to and interact with other stressors of ecosystem processes, including surface-water diversions, losses of spawning and rearing habitats, nonnative species, and harmful...
Constraints on the history and topography of the Northeastern Sierra Nevada from a Neogene sedimentary basin in the Reno-Verdi area, Western Nevada
James Trexler, Patricia Cashman, Michael Cosca
2012, Geosphere (8) 548-561
Neogene (Miocene–Pliocene) sedimentary rocks of the northeastern Sierra Nevada were deposited in small basins that formed in response to volcanic and tectonic activity along the eastern margin of the Sierra. These strata record an early phase (ca. 11–10 Ma) of extension and rapid sedimentation of boulder conglomerates and debrites deposited...
Density-dependent nest predation in waterfowl: the relative importance of nest density versus nest dispersion
Joshua T. Ackerman, Kevin M. Ringelman, J.M. Eadie
2012, Oecologia (169) 695-702
When nest predation levels are very high or very low, the absolute range of observable nest success is constrained (a floor/ceiling effect), and it may be more difficult to detect density-dependent nest predation. Density-dependent nest predation may be more detectable in years with moderate predation rates, simply because there can...
Evaluation of carbon fluxes and trends (2000-2008) in the Greater Platte River Basin: a sustainability study on the potential biofuel feedstock development
Yingxin Gu, Bruce K. Wylie, Li Zhang, Tagir G. Gilmanov
2012, Biomass and Bioenergy (47) 145-152
This study evaluates the carbon fluxes and trends and examines the environmental sustainability (e.g., carbon budget, source or sink) of the potential biofuel feedstock sites identified in the Greater Platte River Basin (GPRB). A 9-year (2000–2008) time series of net ecosystem production (NEP), a measure of net carbon absorption or...
Effects of supplemental feeding and aggregation on fecal glucocorticoid metabolite concentrations in elk
Victoria E. Forristal, Scott Creel, Mark L. Taper, Brandon M. Scurlock, Paul C. Cross
2012, Journal of Wildlife Management (76) 76-4
Habitat modifications and supplemental feeding artificially aggregate some wildlife populations, with potential impacts upon contact and parasite transmission rates. Less well recognized, however, is how increased aggregation may affect wildlife physiology. Crowding has been shown to induce stress responses, and increased glucocorticoid (GC) concentrations can reduce immune function and increase...
Estimating risks to aquatic life using quantile regression
Travis S. Schmidt, William H. Clements, Brian S. Cade
2012, Freshwater Science (31) 709-723
One of the primary goals of biological assessment is to assess whether contaminants or other stressors limit the ecological potential of running waters. It is important to interpret responses to contaminants relative to other environmental factors, but necessity or convenience limit quantification of all factors that influence ecological potential. In...
Strategies to control a common carp population by pulsed commercial harvest
Michael E. Colvin, Clay Pierce, Timothy W. Stewart, Scott E. Grummer
2012, North American Journal of Fisheries Management (32) 1251-1264
Commercial fisheries are commonly used to manage nuisance fishes in freshwater systems, but such efforts are often unsuccessful. Strategies for successfully controlling a nuisance population of common carp Cyprinus carpio by pulsed commercial harvest were evaluated with a combination of (1) field sampling, (2) population estimation and CPUE indexing, and (3) simulation...
Effects of climate change and population growth on the transboundary Santa Cruz aquifer
Christopher A. Scott, Sharon Megdal, Lucas Antonio Oroz, James Callegary, Prescott Vandervoet
2012, Climate Research (51) 159-170
The USA and Mexico have initiated comprehensive assessment of 4 of the 18 aquifers underlying their 3000 km border. Binational management of groundwater is not currently proposed. University and agency researchers plus USA and Mexican federal, state, and local agency staff have collaboratively identified key challenges facing the Santa Cruz...
The GED4GEM project: development of a Global Exposure Database for the Global Earthquake Model initiative
P. Gamba, D. Cavalca, K. S. Jaiswal, C. Huyck, H. Crowley
2012, Conference Paper, The 15th World Conference on Earthquake Engineering: September 24-28, 2012, Lisbon, Portugal
In order to quantify earthquake risk of any selected region or a country of the world within the Global Earthquake Model (GEM) framework (www.globalquakemodel.org/), a systematic compilation of building inventory and population exposure is indispensable. Through the consortium of leading institutions and by engaging the domain-experts from multiple countries, the...
Complementarity of ResourceSat-1 AWiFS and Landsat TM/ETM+ sensors
S.N. Goward, G. Chander, M. Pagnutti, A. Marx, R. Ryan, N. Thomas, R. Tetrault
2012, Remote Sensing of Environment (123) 41-56
Considerable interest has been given to forming an international collaboration to develop a virtual moderate spatial resolution land observation constellation through aggregation of data sets from comparable national observatories such as the US Landsat, the Indian ResourceSat and related systems. This study explores the complementarity of India's ResourceSat-1 Advanced Wide...
Comparison of soil thickness in a zero-order basin in the Oregon Coast Range using a soil probe and electrical resistivity tomography
Michael S. Morse, Ning Lu, Jonathan W. Godt, André Revil, Jeffrey A. Coe
2012, Journal of Geotechnical and Geoenvironmental Engineering (138) 1470-1482
Accurate estimation of the soil thickness distribution in steepland drainage basins is essential for understanding ecosystem and subsurface response to infiltration. One important aspect of this characterization is assessing the heavy and antecedent rainfall conditions that lead to shallow landsliding. In this paper, we investigate the direct current (DC) resistivity...
Foraging optimally for home ranges
Michael S. Mitchell, Roger A. Powell
2012, Journal of Mammalogy (93) 917-928
Economic models predict behavior of animals based on the presumption that natural selection has shaped behaviors important to an animal's fitness to maximize benefits over costs. Economic analyses have shown that territories of animals are structured by trade-offs between benefits gained from resources and costs of defending them. Intuitively, home...
Resolving hyporheic and groundwater components of streambed water flux
Aditi S. Bhaskar, Judson W. Harvey, Eric J. Henry
2012, Water Resources Research (48)
Hyporheic and groundwater fluxes typically occur together in permeable sediments beneath flowing stream water. However, streambed water fluxes quantified using the thermal method are usually interpreted as representing either groundwater or hyporheic fluxes. Our purpose was to improve understanding of co-occurring groundwater and hyporheic fluxes using streambed temperature measurements and...
Anisotropic path modeling to assess pedestrian-evacuation potential from Cascadia-related tsunamis in the US Pacific Northwest
Nathan J. Wood, Mathew C. Schmidtlein
2012, Natural Hazards (62) 275-300
Recent disasters highlight the threat that tsunamis pose to coastal communities. When developing tsunami-education efforts and vertical-evacuation strategies, emergency managers need to understand how much time it could take for a coastal population to reach higher ground before tsunami waves arrive. To improve efforts to model pedestrian evacuations from tsunamis,...
Correlation of resource plays and biodiversity patterns: accumulation of organic-rich shale tracks taxonomic turnover
Jennifer D. Eoff
2012, GCAGS Journal (1) 1-12
Similar paleogeographic and paleotectonic settings characterize most self-sourced shale hydrocarbon plays. Their deposition occurred within similar orders of magnitude of eustatic events and during geologic periods characterized by “warm” (or transitional) climates and calcitic seas. In addition, the stratigraphic occurrence of shale plays parallels certain historical patterns of marine metazoan...
New insights into gill ionocyte and ion transporter function in euryhaline and diadromous fish
Junya Hiroi, Stephen D. McCormick
2012, Respiratory Physiology and Neurobiology (184) 257-268
Teleost fishes are able to acclimatize to seawater by secreting excess NaCl by means of specialized “ionocytes” in the gill epithelium. Antibodies against Na+/K+-ATPase (NKA) have been used since 1996 as a marker for identifying branchial ionocytes. Immunohistochemistry of NKA by itself and in combination with Na+/K+/2Cl− cotransporter and CFTR...
Airborne LiDAR analysis and geochronology of faulted glacial moraines in the Tahoe-Sierra frontal fault zone reveal substantial seismic hazards in the Lake Tahoe region, California-Nevada USA
James F. Howle, Gerald W. Bawden, Richard A. Schweickert, Robert C. Finkel, Lewis E. Hunter, Ronn S. Rose, Brent von Twistern
2012, GSA Bulletin (124) 1087-1101
We integrated high-resolution bare-earth airborne light detection and ranging (LiDAR) imagery with field observations and modern geochronology to characterize the Tahoe-Sierra frontal fault zone, which forms the neotectonic boundary between the Sierra Nevada and the Basin and Range Province west of Lake Tahoe. The LiDAR imagery clearly delineates active normal...
