Methods for monitoring corals and crustose coralline algae to quantify in-situ calcification rates
Jennifer M. Morrison, Ilsa B. Kuffner, T. Don Hickey
2013, Open-File Report 2013-1159
The potential effect of global climate change on calcifying marine organisms, such as scleractinian (reef-building) corals, is becoming increasingly evident. Understanding the process of coral calcification and establishing baseline calcification rates are necessary to detect future changes in growth resulting from climate change or other stressors. Here we describe the...
Species- and community-level responses combine to drive phenology of lake phytoplankton
Annika Walters, Maria de los Angeles Gonzalez Sagrario, Daniel E. Schindler
2013, Ecology (94) 2188-2194
Global change is leading to shifts in the seasonal timing of growth and maturation for primary producers. Remote sensing is increasingly used to measure the timing of primary production in both aquatic and terrestrial ecosystems, but there is often a poor correlation between these results and direct observations of life-history...
Predicting the planform configuration of the braided Toklat River, AK with a suite of rule-based models
Charles J. Podolak
2013, Journal of the American Water Resources Association (49) 390-401
An ensemble of rule-based models was constructed to assess possible future braided river planform configurations for the Toklat River in Denali National Park and Preserve, Alaska. This approach combined an analysis of large-scale influences on stability with several reduced-complexity models to produce the predictions at a practical level for managers...
Distribution and exploitation of Nile perch Lates niloticus in relation to stratification in Lake Victoria, East Africa
A. Taabu-Munyaho, Robert J. Kayanda, Inigo Everson, Timothy B. Grabowski, Gudrun Marteinsdottir
2013, Journal of Great Lakes Research (39) 466-475
Stratification restricts habitable areas forcing fish to balance between favourable temperature and minimum dissolved oxygen requirements. Acoustic surveys conducted during the stratified and isothermal periods on tropical Lake Victoria indicated that stratification of temperature and dissolved oxygen (DO) affected vertical distribution of Nile perch. There was higher mean temperature (25.6...
Environmental and physical controls on northern terrestrial methane emissions across permafrost zones
David Olefeldt, Merritt R. Turetsky, Patrick M. Crill, A. David McGuire
2013, Global Change Biology (19) 589-603
Methane (CH4) emissions from the northern high-latitude region represent potentially significant biogeochemical feedbacks to the climate system. We compiled a database of growing-season CH4 emissions from terrestrial ecosystems located across permafrost zones, including 303 sites described in 65 studies. Data on environmental and physical variables, including permafrost conditions, were used...
Pre- and post-impoundment nitrogen in the lower Missouri River
Dale W. Blevins, Donald H. Wilkison, Shelley L. Niesen
2013, Hydrological Processes (28) 2535-2549
Large water-sample sets collected from 1899 through 1902, 1907, and in the early 1950s allow comparisons of pre-impoundment and post-impoundment (1969 through 2008) nitrogen concentrations in the lower Missouri River. Although urban wastes were not large enough to detectably increase annual loads of total nitrogen at the beginning of the...
Power to detect trends in abundance of secretive marsh birds: effects of species traits and sampling effort
Robert J. Steidl, Courtney J. Conway, Andrea R. Litt
2013, Journal of Wildlife Management (77) 445-453
Standardized protocols for surveying secretive marsh birds have been implemented across North America, but the efficacy of surveys to detect population trends has not been evaluated. We used survey data collected from populations of marsh birds across North America and simulations to explore how characteristics of bird populations (proportion of...
Permafrost thaw in a nested groundwater-flow system
Jeffery M. McKenzie, Clifford I. Voss
2013, Hydrogeology Journal (21) 299-316
Groundwater flow in cold regions containing permafrost accelerates climate-warming-driven thaw and changes thaw patterns. Simulation analyses of groundwater flow and heat transport with freeze/thaw in typical cold-regions terrain with nested flow indicate that early thaw rate is particularly enhanced by flow, the time when adverse environmental impacts of climate-warming-induced permafrost...
A twenty-first century California observing network for monitoring extreme weather events
A.B. White, M.L. Anderson, M. D. Dettinger, F.M. Ralph, A. Hinojosa, D.R. Cayan, R.K. Hartman, D.W. Reynolds, L.E. Johnson, T.L. Schneider, R. Cifelli, Z. Toth, S.I. Gutman, C.W. King, F. Gehrke, P.E. Johnston, C. Walls, Dorte Mann, D.J. Gottas, T. Coleman
2013, Journal of Atmospheric and Oceanic Technology (30) 1585-1603
During Northern Hemisphere winters, the West Coast of North America is battered by extratropical storms. The impact of these storms is of paramount concern to California, where aging water supply and flood protection infrastructures are challenged by increased standards for urban flood protection, an unusually variable weather regime, and projections...
On the conversion of tritium units to mass fractions for hydrologic applications
David A. Stonestrom, Brian J. Andraski, Clay A. Cooper, Charles J. Mayers, Robert L. Michel
2013, Isotopes in Environmental and Health Studies (49) 250-256
We develop a general equation for converting laboratory-reported tritium levels, expressed either as concentrations (tritium isotope number fractions) or mass-based specific activities, to mass fractions in aqueous systems. Assuming that all tritium is in the form of monotritiated water simplifies the derivation and is shown to be reasonable for most...
Observed impacts of duration and seasonality of atmospheric-river landfalls on soil moisture and runoff in coastal northern California
F.M. Ralph, T. Coleman, P.J. Neiman, R.J. Zamora, Mike Dettinger
2013, Journal of Hydrometeorology (14) 443-459
This study is motivated by diverse needs for better forecasts of extreme precipitation and floods. It is enabled by unique hourly observations collected over six years near California’s Russian River and by recent advances in the science of atmospheric rivers (ARs). This study fills key gaps limiting the prediction of...
Estimating occupancy and predicting numbers of gray wolf packs in Montana using hunter surveys
Lindsey N. Rich, Robin E. Russell, Elizabeth M. Glenn, Michael S. Mitchell, Justin A. Gude, Kevin M. Podruzny, Carolyn A. Sime, Kent Laudon, David E. Ausband, James D. Nichols
2013, Journal of Wildlife Management (77) 1280-1289
Reliable knowledge of the status and trend of carnivore populations is critical to their conservation and management. Methods for monitoring carnivores, however, are challenging to conduct across large spatial scales. In the Northern Rocky Mountains, wildlife managers need a time- and cost-efficient method for monitoring gray wolf (Canis lupus) populations....
Water supply, demand, and quality indicators for assessing the spatial distribution of water resource vulnerability in the Columbia River Basin
Heejun Chang, Il-Won Jung, Angela L. Strecker, Daniel Wise, Martin Lafrenz, Vivek Shandas, Moradkhani, Alan Yeakley, Yangdong Pan, Gunnar Johnson, Mike Psaris
2013, Atmosphere - Ocean (51) 339-356
We investigated water resource vulnerability in the US portion of the Columbia River basin (CRB) using multiple indicators representing water supply, water demand, and water quality. Based on the US county scale, spatial analysis was conducted using various biophysical and socio-economic indicators that control water vulnerability. Water supply vulnerability and...
Geologic map of the Valley Mountain 15’ quadrangle, San Bernardino and Riverside Counties, California
Keith A. Howard, John Bacheller, Todd T. Fitzgibbon, Robert E. Powell, Charlotte M. Allen
2013, Geologic Quadrangle 1767
The Valley Mountain 15’ quadrangle straddles the Pinto Mountain Fault, which bounds the eastern Transverse Ranges in the south against the Mojave Desert province in the north. The Pinto Mountains, part of the eastern Transverse Ranges in the south part of the quadrangle expose a series of Paleoproterozoic gneisses and...
Local-area-enhanced, 2.5-meter resolution natural-color and color-infrared satellite-image mosaics of the Parwan mineral district in Afghanistan: Chapter CC in Local-area-enhanced, high-resolution natural-color and color-infrared satellite-image mosaics of mineral districts in Afghanistan
Philip A. Davis
2013, Data Series 709-CC
The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Defense Task Force for Business and Stability Operations, prepared databases for mineral-resource target areas in Afghanistan. The purpose of the databases is to (1) provide useful data to ground-survey crews for use in performing detailed assessments of the...
Mercury cycling in agricultural and managed wetlands of California: seasonal influences of vegetation on mercury methylation, storage, and transport
Lisamarie Windham-Myers, Mark C. Marvin-DiPasquale, Evangelos Kakouros, Jennifer L. Agee, Le H. Kieu, Craig A. Stricker, Jacob A. Fleck, Joshua T. Ackerman
2013, Science of the Total Environment
Plants are a dominant biologic and physical component of many wetland capable of influencing the internal pools and fluxes of methylmercury (MeHg). To investigate their role with respect to the latter, we examined the changing seasonal roles of vegetation biomass and Hg, C and N composition from May 2007-February 2008...
Mapping wildfire burn severity in the Arctic Tundra from downsampled MODIS data
Crystal A. Kolden, John Rogan
2013, Arctic, Antarctic, and Alpine Research (45) 64-76
Wildfires are historically infrequent in the arctic tundra, but are projected to increase with climate warming. Fire effects on tundra ecosystems are poorly understood and difficult to quantify in a remote region where a short growing season severely limits ground data collection. Remote sensing has been widely utilized to characterize...
The role of vermetid gastropods in the development of the Florida Middle Ground, northeast Gulf of Mexico
Christopher D. Reich, Richard Z. Poore, Todd D. Hickey
2013, Journal of Coastal Research 46-57
The Florida Middle Ground is a complex of north to northwest trending ridges that lie approximately 180 km northwest of Tampa Bay, Florida. The irregular ridges appear on the otherwise gently sloping West Florida shelf and exhibit between 10-15 m of relief. Modern studies interpret the ridges as remnants of...
Sr/Ca proxy sea-surface temperature reconstructions from modern and holocene Montastraea faveolata specimens from the Dry Tortugas National Park
Jennifer A. Flannery, Richard Z. Poore
2013, Journal of Coastal Research (63) 20-31
Sr/Ca ratios from skeletal samples from two Montastraea faveolata corals (one modern, one Holocene, ~6 Ka) from the Dry Tortugas National Park were measured as a proxy for sea-surface temperature (SST). We sampled coral specimens with a computer-driven triaxial micromilling machine, which yielded an average of 15 homogenous samples per...
An examination of historic inorganic sedimentation and organic matter accumulation in several marsh types within the Mobile Bay and and Mobile-Tensaw River Delta region
Christopher G. Smith, Lisa E. Osterman, Richard Z. Poore
2013, Journal of Coastal Research (63) 68-83
Mass accumulation rates (MAR; g cm-2 y-1), linear sedimentation rates (LSR; cm y-1), and core geochronology derived from excess lead-210 (210Pb) profiles and inventories measured in six sediment cores collected from marsh sites from the MobileTensaw River Delta and Mobile Bay region record the importance of both continuous and event-driven...
Intercontinental migratory connectivity and population structuring of Dunlins from western Alaska
Robert E. Gill Jr., Colleen M. Handel, Daniel R. Ruthrauff
2013, The Condor (115) 525-534
The Dunlin (Calidris alpina) is a polytypic shorebird with complex patterns of distribution and migration throughout its holarctic range. We analyzed mark-re sighting data obtained between 1977 and 2010 from birds captured at two major staging areas in western Alaska to test the hypothesis that the migration patterns of Alaskan...
Hydrogeology, groundwater seepage, nitrate distribution, and flux at the Raleigh hydrologic research station, Wake County, North Carolina, 2005-2007
Kristen Bukowski McSwain, Richard E. Bolich, Melinda J. Chapman
2013, Scientific Investigations Report 2013-5041
rom 2005 to 2007, the U.S. Geological Survey and the North Carolina Department of Environment and Natural Resources, Division of Water Quality, conducted a study to describe the geologic framework, measure groundwater quality, characterize the groundwater-flow system, and describe the groundwater/surface-water interaction at the 60-acre Raleigh hydrogeologic research station (RHRS)...
New Method for Electrical Conductivity Temperature Compensation
R. Blaine McCleskey
2013, Environmental Science & Technology (47) 9874-9881
Electrical conductivity (κ) measurements of natural waters are typically referenced to 25 °C (κ25) using standard temperature compensation factors (α). For acidic waters (pH < 4), this can result in a large κ25 error (δκ25). The more the sample temperature departs from 25 °C, the larger the potential δκ25. For...
Pb-Sr-Nd isotopes in surficial materials at the Pebble Porphyry Cu-Au-Mo Deposit, Southwestern Alaska: can the mineralizing fingerprint be detected through cover?
Robert A. Ayuso, Karen D. Kelley, Robert G. Eppinger, Francesca Forni
2013, Economic Geology (108) 543-563
The Cretaceous Pebble porphyry Cu-Au-Mo deposit is covered by tundra and glacigenic sediments. Pb-Sr-Nd measurements were done on sediments and soils to establish baseline conditions prior to the onset of mining operations and contribute to the development of exploration methods for concealed base metal deposits of this type. Pebble rocks...
A combined radio- and stable-isotopic study of a California coastal aquifer system
Peter W. Swarzenski, Mark Baskaran, Robert J. Rosenbauer, Brian D. Edwards, Michael Land
2013, Water (5) 480-504
Stable and radioactive tracers were utilized in concert to characterize geochemical processes in a complex coastal groundwater system and to provide constraints on the kinetics of rock/water interactions. Groundwater samples from wells within the Dominguez Gap region of Los Angeles County, California were analyzed for a suite of major cations...
