Linking ground-water age and chemistry data along flow paths: Implications for trends and transformations of nitrate and pesticides
A. J. Tesoriero, D. A. Saad, K.R. Burow, E. A. Frick, L.J. Puckett, J.E. Barbash
2007, Journal of Contaminant Hydrology (94) 139-155
Tracer-based ground-water ages, along with the concentrations of pesticides, nitrogen species, and other redox-active constituents, were used to evaluate the trends and transformations of agricultural chemicals along flow paths in diverse hydrogeologic settings. A range of conditions affecting the transformation of nitrate and pesticides (e.g., thickness of unsaturated zone, redox...
A GIS-based groundwater travel time model to evaluate stream nitrate concentration reductions from land use change
K. E. Schilling, C.F. Wolter
2007, Environmental Geology (53) 433-443
Excessive nitrate-nitrogen (nitrate) loss from agricultural watersheds is an environmental concern. A common conservation practice to improve stream water quality is to retire vulnerable row croplands to grass. In this paper, a groundwater travel time model based on a geographic information system (GIS) analysis of readily available soil and topographic...
Using topographic lidar data to delineate the North Carolina Shoreline
Patrick W. Limber, Jeffrey H. List, Jeffrey D. Warren, Amy S. Farris, Kathryn M. Weber
2007, Conference Paper, Coastal Sediments '07 - Proceedings of 6th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
In North Carolina, shoreline change rates are an important component of the state's coastal management program. To enhance methods of measuring shoreline change, the NC Division of Coastal Management (DCM) is considering using mean high water (MHW) shorelines extracted from lidar data together with traditional wet/dry shorelines digitized from aerial...
Interaction and influence of two creeks on Escherichia coli concentrations of nearby beaches: Exploration of predictability and mechanisms
M.B. Nevers, R.L. Whitman, W.E. Frick, Z. Ge
2007, Journal of Environmental Quality (36) 1338-1345
The impact of river outfalls on beach water quality depends on numerous interacting factors. The delivery of contaminants by multiple creeks greatly complicates understanding of the source contributions, especially when pollution might originate up- or down-coast of beaches. We studied two beaches along Lake Michigan that are located between two...
Potential hazards of environmental contaminants to avifauna residing in the Chesapeake Bay estuary
Barnett A. Rattner, Peter C. McGowan
2007, Waterbirds (30) 63-81
A search of the Contaminant Exposure and Effects-Terrestrial Vertebrates (CEE-TV) database revealed that 70% of the 839 Chesapeake Bay records deal with avian species. Studies conducted on waterbirds in the past 15 years indicate that organochlorine contaminants have declined in eggs and tissues, although p,p'-DDE, total polychlorinated biphenyls (PCBs) and...
Prescribed fire and cutting as tools for reducing woody plant succession in a created salt marsh
A.B. Owens, C.E. Proffitt, J.B. Grace
2007, Wetlands Ecology and Management (15) 405-416
This paper reports on efforts to reduce woody successional growth by the native shrub Iva frutescens L. in a created salt marsh by using prescribed fire and cutting. Experimental treatments included a winter burn, cutting plants at ground level, and a combination burn-and-cut treatment, with replicate plots of each. Iva...
High nutrient pulses, tidal mixing and biological response in a small California estuary: Variability in nutrient concentrations from decadal to hourly time scales
J.M. Caffrey, T.P. Chapin, H.W. Jannasch, J.C. Haskins
2007, Estuarine, Coastal and Shelf Science (71) 368-380
Elkhorn Slough is a small estuary in Central California, where nutrient inputs are dominated by runoff from agricultural row crops, a golf course, and residential development. We examined the variability in nutrient concentrations from decadal to hourly time scales in Elkhorn Slough to compare forcing by physical and biological factors....
Sorted bed forms as self-organized patterns: 2. complex forcing scenarios
Giovanni Coco, A. Brad Murray, Malcom O. Green, E. Robert Thieler, T.M. Hume
2007, Journal of Geophysical Research F: Earth Surface (112)
We employ a numerical model to study the development of sorted bed forms under a variety of hydrodynamic and sedimentary conditions. Results indicate that increased variability in wave height decreases the growth rate of the features and can potentially give rise to complicated, a priori unpredictable, behavior. This happens because...
Long-term performance of Aanderaa optodes and sea-bird SBE-43 dissolved-oxygen sensors bottom mounted at 32 m in Massachusetts Bay
Marinna A. Martini, Bradford Butman, Michael J. Mickelson
2007, Journal of Atmospheric and Oceanic Technology (24) 1924-1935
A field evaluation of two new dissolved-oxygen sensing technologies, the Aanderaa Instruments AS optode model 3830 and the Sea-Bird Electronics, Inc., model SBE43, was carried out at about 32-m water depth in western Massachusetts Bay. The optode is an optical sensor that measures fluorescence quenching by oxygen molecules, while the...
Comparison of local- to regional-scale estimates of ground-water recharge in Minnesota, USA
G. N. Delin, R. W. Healy, D. L. Lorenz, J. R. Nimmo
2007, Journal of Hydrology (334) 231-249
Regional ground-water recharge estimates for Minnesota were compared to estimates made on the basis of four local- and basin-scale methods. Three local-scale methods (unsaturated-zone water balance, water-table fluctuations (WTF) using three approaches, and age dating of ground water) yielded point estimates of recharge that represent spatial scales from about 1...
Forcing of large-scale cycles of coastal change at the entrance to Willapa Bay, Washington
Robert A. Morton, H. Edward Clifton, Noreen A. Buster, Russell L. Peterson, Guy Gelfenbaum
2007, Marine Geology (246) 24-41
Anomalous morphological features within large estuaries may be: (1) recorders of external forces that periodically overwhelm the normal morphodynamic responses to estuarine energy fluxes, and (2) possible predictors of cycles of future coastal change. At the entrance to Willapa Bay, Washington, chronic beach erosion and frequent coastal flooding are related...
Evidence of lake whitefish spawning in the Detroit River: Implications for habitat and population recovery
E.F. Roseman, G.W. Kennedy, J. Boase, B.A. Manny, T. N. Todd, W. Stott
2007, Journal of Great Lakes Research (33) 397-406
Historic reports imply that the lower Detroit River was once a prolific spawning area for lake whitefish (Coregonus clupeaformis) prior to the construction of the Livingstone shipping channel in 1911. Large numbers of lake whitefish migrated into the river in fall where they spawned on expansive limestone bedrock and gravel...
Controls on the Karaha-Telaga Bodas geothermal reservoir, Indonesia
M. Nemcok, J.N. Moore, Carl Christensen, R. Allis, T. Powell, B. Murray, G. Nash
2007, Geothermics (36) 9-46
Karaha-Telaga Bodas is a partially vapor-dominated, fracture-controlled geothermal system located adjacent to Galunggung Volcano in western Java, Indonesia. The geothermal system consists of: (1) a caprock, ranging from several hundred to 1600 m in thickness, and characterized by a steep, conductive temperature gradient and low permeability; (2) an underlying vapor-dominated...
Sandy signs of a tsunami's onshore depth and speed
K. Huntington, J. Bourgeois, G. Gelfenbaum, P. Lynett, B. Jaffe, H. Yeh, R. Weiss
2007, Eos, Transactions, American Geophysical Union (88) 577-578
Tsunamis rank among the most devastating and unpredictable natural hazards to affect coastal areas. Just 3 years ago, in December 2004, the Indian Ocean tsunami caused more than 225,000 deaths. Like many extreme events, however, destructive tsunamis strike rarely enough that written records span too little time to quantify tsunami...
Microbial sulfate reduction and metal attenuation in pH 4 acid mine water
C.D. Church, R.T. Wilkin, Charles N. Alpers, R. O. Rye, R.B. Blaine
2007, Geochemical Transactions (8)
Sediments recovered from the flooded mine workings of the Penn Mine, a Cu-Zn mine abandoned since the early 1960s, were cultured for anaerobic bacteria over a range of pH (4.0 to 7.5). The molecular biology of sediments and cultures was studied to determine whether sulfate-reducing bacteria (SRB) were active in...
The occurrence of the colonial ascidian Didemnum sp. on Georges Bank gravel habitat: ecological observations and potential effects on groundfish and scallop fisheries
P. C. Valentine, J.S. Collie, R.N. Reid, R. G. Asch, Vincent G. Guida, D.S. Blackwood
2007, Journal of Experimental Marine Biology and Ecology (342) 179-181
The colonial ascidian Didemnum sp. is present on the Georges Bank fishing grounds in a gravel habitat where the benthic invertebrate fauna has been monitored annually since 1994. The species was not noted before 2002 when large colonies were first observed; and by 2003 and 2004 it covered large areas...
Incidence of the enterococcal surface protein (esp) gene in human and animal fecal sources
R.L. Whitman, K. Przybyla-Kelly, D.A. Shively, M.N. Byappanahalli
2007, Environmental Science & Technology (41) 6090-6095
The occurrence of the enterococcal surface protein (esp) gene in the opportunistic pathogens Enterococcus faecalis and E. faecium is well-documented in clinical research. Recently, the esp gene has been proposed as a marker of human pollution in environmental waters; however, information on its relative incidence in various human and animal...
Natural landscape and stream segment attributes influencing the distribution and relative abundance of riverine smallmouth bass in Missouri
S.K. Brewer, C.F. Rabeni, S.P. Sowa, G. Annis
2007, North American Journal of Fisheries Management (27) 326-341
Protecting and restoring fish populations on a regional basis are most effective if the multiscale factors responsible for the relative quality of a fishery are known. We spatially linked Missouri's statewide historical fish collections to environmental features in a geographic information system, which was used as a basis for modeling...
Structure and composition of a watershed-scale sediment information network
W. R. Osterkamp, J. R. Gray, J.B. Laronne, J.R. Martin
2007, International Journal of Sediment Research (22) 238-246
A 'Watershed-Scale Sediment Information Network' (WaSSIN), designed to complement UNESCO's International Sedimentation Initiative, was endorsed as an initial project by the World Association for Sedimentation and Erosion Research. WaSSIN is to address global fluvial-sediment information needs through a network approach based on consistent protocols for the collection, analysis, and storage...
Investigation of the groundwater system at Masaya Caldera, Nicaragua, using transient electromagnetics and numerical simulation
R.E. MacNeil, W. E. Sanford, C.B. Connor, S.K. Sandberg, M. Diez
2007, Journal of Volcanology and Geothermal Research (166) 217-232
The distribution of groundwater beneath Masaya Volcano, in Nicaragua, and its surrounding caldera was characterized using the transient electromagnetic method (TEM). Multiple soundings were conducted at 30 sites. Models of the TEM data consistently indicate a resistive layer that is underlain by one or more conductive layers. These two layers...
A condensed middle Cenomanian succession in the Dakota Sandstone (Upper Cretaceous), Sevilleta National Wildlife Refuge, Socorro County, New Mexico
Stephen C. Hook, William A. Cobban
2007, New Mexico Geology (29) 75-96
The upper part of the Dakota Sandstone exposed on the Sevilleta National Wildlife Refuge, northern Socorro County, New Mexico, is a condensed, Upper Cretaceous, marine succession spanning the first five middle Cenomanian ammonite zones of the U.S. Western Interior. Farther north in New Mexico these five ammonite zones occur over...
Temporal changes of populations and trophic relationships of wintering diving ducks in Chesapeake Bay
Matthew C. Perry, Alicia M. Wells-Berlin, David M. Kidwell, Peter C. Osenton
2007, Waterbirds (30) 4-16
Population and trophic relationships among diving ducks in Chesapeake Bay are diverse and complex as they include five species of bay ducks (Aythya spp.), nine species of seaducks (Tribe Mergini), and the Ruddy Duck (Oxyura jamaicensis). Here we considered the relationships between population changes and diet over the past half...
Multiscale habitat selection by burrowing owls in black-tailed prairie dog colonies
S.J. Lantz, C.J. Conway, S.H. Anderson
2007, Journal of Wildlife Management (71) 2664-2672
Some populations of western burrowing owls (Athene cunicularia hypugaea) have declined in recent decades. To design and implement effective recovery efforts, we need a better understanding of how distribution and demographic traits are influenced by habitat quality. To this end, we measured spatial patterns of burrowing owl breeding habitat selection...
Preliminary testing of the role of exercise and predator recognition for bonytail and razorback sucker
Gordon A. Mueller, Jeanette Carpenter, Robert Krapfel, Chester Figiel
2007, Open-File Report 2007-1423
Hatchery-reared juvenile, <25-cm TL (total length), razorback suckers appeared curious and showed no sign of predator avoidance when initially placed with large (>45-cm TL) flathead catfish. Predator-naïve juveniles (20- to 25-cm TL) exhibited no discernable preference when provided areas with and without (52 percent and 48 percent, n = 16...
A coupled remote sensing and simplified surface energy balance approach to estimate actual evapotranspiration from irrigated fields
G.B. Senay, Michael Budde, J. P. Verdin, Assefa M. Melesse
2007, Sensors (7) 979-1000
Accurate crop performance monitoring and production estimation are critical for timely assessment of the food balance of several countries in the world. Since 2001, the Famine Early Warning Systems Network (FEWS NET) has been monitoring crop performance and relative production using satellite-derived data and simulation models in Africa, Central America,...
