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Page 695, results 17351 - 17375

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Not all publications have extents, not all extents are completely accurate
Assessment of pingo distribution and morphometry using an IfSAR derived digital surface model, western Arctic Coastal Plain, Northern Alaska
Benjamin M. Jones, G. Grosse, Kenneth M. Hinkel, C.D. Arp, S. Walker, R.A. Beck, J. P. Galloway
2012, Geomorphology (138) 1-14
Pingos are circular to elongate ice-cored mounds that form by injection and freezing of pressurized water in near-surface permafrost. Here we use a digital surface model (DSM) derived from an airborne Interferometric Synthetic Aperture Radar (IfSAR) system to assess the distribution and morphometry of pingos within a 40,000 km2 area on the...
A preliminary assessment of the spatial sources of contemporary suspended sediment in the Ohio River basin, United States, using water quality data from the NASQAN programme in a source tracing procedure
Y.-S. Zhang, A.L. Collins, Arthur J. Horowitz
2012, Hydrological Processes (26) 326-334
Reliable information on catchment scale suspended sediment sources is required to inform the design of management strategies for helping abate the numerous environmental issues associated with enhanced sediment mobilization and off‐site loadings. Since sediment fingerprinting techniques avoid many of the logistical constraints associated with using more traditional indirect measurement methods...
Three-dimensional sensitivity distribution and sample volume of low-induction-number electromagnetic-induction instruments
James B. Callegary, T.P.A. Ferre, R.W. Groom
2012, Soil Science Society of America Journal (76) 85-91
There is an ongoing effort to improve the understanding of the correlation of soil properties with apparent soil electrical conductivity as measured by low‐induction‐number electromagnetic‐induction (LIN FEM) instruments. At a minimum, the dimensions of LIN FEM instruments' sample volume, the spatial distribution of sensitivity within that volume, and implications for...
Quantifying riverine surface currents from time sequences of thermal infrared imagery
Jack A. Puleo, T.E. McKenna, K. T. Holland, J. Calantoni
2012, Water Resources Research (48)
River surface currents are quantified from thermal and visible band imagery using two methods. One method utilizes time stacks of pixel intensity to estimate the streamwise velocity at multiple locations. The other method uses particle image velocimetry to solve for optimal two-dimensional pixel displacements between successive frames. Field validation was...
Functional ecology of saltglands in shorebirds: Flexible responses to variable environmental conditions
J.S. Gutierrez, M.W. Dietz, J.A. Masero, Robert E. Gill Jr., Anne Dekinga, Phil F. Battley, J. M. Sanchez-Guzman, Theunis Piersma
2012, Functional Ecology (26) 236-244
1. Birds of marine environments have specialized glands to excrete salt, the saltglands. Located on the skull between the eyes, the size of these organs is expected to reflect their demand, which will vary with water turnover rates as a function of environmental (heat load, salinity of prey and drinking...
Effects of suture material and ultrasonic transmitter size on survival, growth, wound healing, and tag expulsion in rainbow trout
Tomas J. Ivasauskas, Phillip William Bettoli, T. Holt
2012, Transactions of the American Fisheries Society (141) 100-106
We examined the effects of suture material (braided silk versus Monocryl) and relative ultrasonic transmitter size on healing, growth, mortality, and tag retention in rainbow trout Oncorhynchus mykiss. In experiment 1, 40 fish (205–281 mm total length [TL], 106–264 g) were implanted with Sonotronics IBT‐96–2 (23 × 7 mm; weight in...
Numerical models of salt marsh evolution: Ecological, geomorphic, and climatic factors
S. Fagherazzi, M. L. Kirwan, S.M. Mudd, G.R. Guntenspergen, S. Temmerman, A. D'Alpaos, J. Van De Koppel, J.M. Rybczyk, E. Reyes, C. Craft, J. Clough
2012, Reviews of Geophysics (50)
Salt marshes are delicate landforms at the boundary between the sea and land. These ecosystems support a diverse biota that modifies the erosive characteristics of the substrate and mediates sediment transport processes. Here we present a broad overview of recent numerical models that quantify the formation and evolution of salt...
Fate and transport of glyphosate and aminomethylphosphonic acid in surface waters of agricultural basins
Richard H. Coupe, Stephen J. Kalkhoff, Paul D. Capel, Caroline Gregoire
2012, Pest Management Science (68) 16-30
BACKGROUND: Glyphosate [N-(phosphonomethyl)glycine] is a herbicide used widely throughout the world in the production of many crops and is heavily used on soybeans, corn and cotton. Glyphosate is used in almost all agricultural areas of the United States, and the agricultural use of glyphosate has increased from less than 10...
Hybrid-optimization algorithm for the management of a conjunctive-use project and well field design
Yung-Chia Chiu, Tracy Nishikawa, Peter Martin
2012, Ground Water (50) 103-117
Hi‐Desert Water District (HDWD), the primary water‐management agency in the Warren Groundwater Basin, California, plans to construct a waste water treatment plant to reduce future septic‐tank effluent from reaching the groundwater system. The treated waste water will be reclaimed by recharging the groundwater basin via recharge ponds as part of...
Nekton density patterns and hurricane recovery in submerged aquatic vegetation, and along non-vegetated natural and created edge habitats
Megan La Peyre, J. Gordon
2012, Estuarine, Coastal and Shelf Science (98) 108-118
We compared nekton habitat value of submerged aquatic vegetation, flooded non-vegetated natural and man-made edge habitats in mesohaline interior marsh areas in southwest Louisiana using a 1-m2 throw trap and 3-mm bag seine. When present, SAV habitats supported close to 4 times greater densities and higher species richness of nekton as compared to either natural or man-made...
Holocene aridification of India
C. Ponton, L. Giosan, T.I. Eglinton, D.Q. Fuller, J.E. Johnson, P. Kumar, Timothy S. Collett
2012, Geophysical Research Letters (39)
Spanning a latitudinal range typical for deserts, the Indian peninsula is fertile instead and sustains over a billion people through monsoonal rains. Despite the strong link between climate and society, our knowledge of the long‐term monsoon variability is incomplete over the Indian subcontinent. Here we reconstruct the Holocene paleoclimate in...
Mercury speciation and transport via submarine groundwater discharge at a southern California coastal lagoon system
P.M. Ganguli, Christopher H. Conaway, Peter W. Swarzenski, J. A. Izbicki, A.R. Flegal
2012, Environmental Science & Technology (46) 1480-1488
We measured total mercury (HgT) and monomethylmercury (MMHg) concentrations in coastal groundwater and seawater over a range of tidal conditions near Malibu Lagoon, California, and used 222Rn-derived estimates of submarine groundwater discharge (SGD) to assess the flux of mercury species to nearshore seawater. We infer a groundwater-seawater mixing scenario based...
Target loads of atmospheric sulfur and nitrogen deposition for protection of acid sensitive aquatic resources in the Adirondack Mountains, New York
T.J. Sullivan, B.J. Cosby, C. T. Driscoll, T.C. McDonnell, A.T. Herlihy, Douglas A. Burns
2012, Water Resources Research (48)
The dynamic watershed acid-base chemistry model of acidification of groundwater in catchments (MAGIC) was used to calculate target loads (TLs) of atmospheric sulfur and nitrogen deposition expected to be protective of aquatic health in lakes in the Adirondack ecoregion of New York. The TLs were calculated for two future dates...
Landslide-dammed lake at Tangjiashan, Sichuan province, China (triggered by the Wenchuan Earthquake, May 12, 2008): Risk assessment, mitigation strategy, and lessons learned
P. Cui, C. Dang, J. Zhuang, Y. You, X. Chen, Kevin M. Scott
2012, Environmental Earth Sciences (65) 1055-1065
Landslides and rock avalanches triggered by the 2008 Wenchuan Earthquake produced 257 landslide dams, mainly situated along the eastern boundary of the Qinghai-Tibet Plateau where rivers descend approximately 3,000 m into the Sichuan Basin. The largest of these dams blocked the Tongkou River (a tributary of the Fujiang River) at Tangjiashan....
A multi-source satellite data approach for modelling Lake Turkana water level: Calibration and validation using satellite altimetry data
N.M. Velpuri, Gabriel B. Senay, K.O. Asante
2012, Hydrology and Earth System Sciences (16) 1-18
Lake Turkana is one of the largest desert lakes in the world and is characterized by high degrees of inter- and intra-annual fluctuations. The hydrology and water balance of this lake have not been well understood due to its remote location and unavailability of reliable ground truth datasets. Managing surface...
An experimental test and models of drift and dispersal processes of pallid sturgeon (Scaphirhynchus albus) free embryos in the Missouri River
P.J. Braaten, D.B. Fuller, R.D. Lott, M.P. Ruggles, T.F. Brandt, R.G. Legare, R.J. Holm
2012, Environmental Biology of Fishes (93) 377-392
Free embryos of wild pallid sturgeon Scaphirhynchus albus were released in the Missouri River and captured at downstream sites through a 180-km reach of the river to examine ontogenetic drift and dispersal processes. Free embryos drifted primarily in the fastest portion of the river channel, and initial drift velocities for...
Seasonal habitat use and selection by grizzly bears in Northern British Columbia
B. Milakovic, K.L. Parker, D.D. Gustine, R.J. Lay, A.B.D. Walker, M.P. Gillingham
2012, Journal of Wildlife Management (76) 170-180
We defined patterns of habitat use and selection by female grizzly bears (Ursus arctos) in the Besa-Prophet watershed of northern British Columbia. We fitted 13 adult females with Geographic Positioning System (GPS) radio-collars and monitored them between 2001 and 2004. We examined patterns of habitat selection by grizzly bears relative...
PhyloChipTM microarray comparison of sampling methods used for coral microbial ecology
Christina A. Kellogg, Yvette M. Piceno, Lauren M. Tom, Todd Z. DeSantis, David G. Zawada, Gary L. Andersen
2012, Journal of Microbiological Methods (88) 103-109
Interest in coral microbial ecology has been increasing steadily over the last decade, yet standardized methods of sample collection still have not been defined. Two methods were compared for their ability to sample coral-associated microbial communities: tissue punches and foam swabs, the latter being less invasive and preferred by reef...
The impact of biotic/abiotic interfaces in mineral nutrient cycling: A study of soils of the Santa Cruz chronosequence, California
A. F. White, M. S. Schulz, D.V. Vivit, T.D. Bullen, J. Fitzpatrick
2012, Geochimica et Cosmochimica Acta (77) 62-85
Biotic/abiotic interactions between soil mineral nutrients and annual grassland vegetation are characterized for five soils in a marine terrace chronosequence near Santa Cruz, California. A Mediterranean climate, with wet winters and dry summers, controls the annual cycle of plant growth and litter decomposition, resulting in net above-ground productivities of...
Soil C and N patterns in a semiarid piñon-juniper woodland: Topography of slope and ephemeral channels add to canopy-intercanopy heterogeneity
Darin J. Law, David D. Breshears, Michael H. Ebinger, Clifton W. Meyer, Craig D. Allen
2012, Journal of Arid Environments (79) 20-24
Carbon and nitrogen are crucial to semiarid woodlands, determining decomposition, production and redistribution of water and nutrients. Carbon and nitrogen are often greater beneath canopies than intercanopies. Upslope vs. downslope position and ephemeral channels might also cause variation in C and N. Yet, few studies have simultaneously evaluated spatial variation...
Using multitemporal remote sensing imagery and inundation measures to improve land change estimates in coastal wetlands
Y.C. Allen, B.R. Couvillion, J.A. Barras
2012, Estuaries and Coasts (35) 190-200
Remote sensing imagery can be an invaluable resource to quantify land change in coastal wetlands. Obtaining an accurate measure of land change can, however, be complicated by differences in fluvial and tidal inundation experienced when the imagery is captured. This study classified Landsat imagery from two wetland areas in coastal...
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...
Selection indicates preference in diverse habitats: A Ground-Nesting bird (charadrius melodus) using reservoir shoreline
M.J. Anteau, M. H. Sherfy, M.T. Wiltermuth
2012, PLoS ONE (7)
Animals use proximate cues to select resources that maximize individual fitness. When animals have a diverse array of available habitats, those selected could give insights into true habitat preferences. Since the construction of the Garrison Dam on the Missouri River in North Dakota, Lake Sakakawea (SAK) has become an important...
Community-level response of fishes and aquatic macroinvertebrates to stream restoration in a third-order tributary of the Potomac River, USA
S.M. Selego, C.L. Rose, G.T. Merovich Jr., Stuart A. Welsh, James T. Anderson
2012, International Journal of Ecology (2012)
Natural stream channel design principles and riparian restoration practices were applied during spring 2010 to an agriculturally impaired reach of the Cacapon River, a tributary of the Potomac River which flows into the Chesapeake Bay. Aquatic macroinvertebrates and fishes were sampled from the restoration reach, two degraded control, and two...
The paleohydrology of unsaturated and saturated zones at Yucca Mountain, Nevada, and vicinity
James B. Paces, Joseph F. Whelan
John S. Stuckless, editor(s)
2012, Book chapter, Hydrology and geochemistry of Yucca Mountain and vicinity, Southern Nevada and California
Surface, unsaturated-zone, and saturated-zone hydrologic conditions at Yucca Mountain responded to past climate variations and are at least partly preserved by sediment, fossil, and mineral records. Characterizing past hydrologic conditions in surface and subsurface environments helps to constrain hydrologic responses expected under future climate conditions and improve predictions of repository...