Findings of the Mars Special Regions Science Analysis Group
D.W. Beaty, K.L. Buxbaum, M.A. Meyer, N. Barlow, W. Boynton, B. Clark, J. Deming, P.T. Doran, K. Edgett, S. Hancock, J. Head, M. Hecht, V. Hipkin, T. Kieft, R. Mancinelli, E. McDonald, C. McKay, M. Mellon, H. Newsom, G. Ori, D. Paige, A.C. Schuerger, M. Sogin, J.A. Spry, A. Steele, K. Tanaka, M. Voytek
2006, Astrobiology (6) 677-732
In summary, within the upper 5 m most of Mars is either too cold or too dry to support the propagation of terrestrial life. However, there are regions that are in disequilibrium, naturally or induced, and could be classified as "special" or, if enough uncertainty exist, could not be declared...
Cloud-to-ground lightning and surface rainfall in warm-season Florida thunderstorms
B. Gungle, E.P. Krider
2006, Journal of Geophysical Research D: Atmospheres (111)
Relationships between cloud-to-ground (CG) lightning and surface rainfall have been examined in nine isolated, warm-season thunderstorms on the east coast of central Florida. CG flashes and the associated rain volumes were measured as a function of time in storm-centered reference frames that followed each storm over a network of rain...
Comparison of local grid refinement methods for MODFLOW
S. Mehl, M. C. Hill, S. A. Leake
2006, Conference Paper, Ground Water
Many ground water modeling efforts use a finite-difference method to solve the ground water flow equation, and many of these models require a relatively fine-grid discretization to accurately represent the selected process in limited areas of interest. Use of a fine grid over the entire domain can be computationally prohibitive;...
Effects of floods on fish assemblages in an intermittent prairie stream
N.R. Franssen, K.B. Gido, C.S. Guy, J.A. Tripe, S.J. Shrank, T.R. Strakosh, K.N. Bertrand, C.M. Franssen, K.L. Pitts, C.P. Paukert
2006, Freshwater Biology (51) 2072-2086
1. Floods are major disturbances to stream ecosystems that can kill or displace organisms and modify habitats. Many studies have reported changes in fish assemblages after a single flood, but few studies have evaluated the importance of timing and intensity of floods on long-term fish assemblage dynamics. 2. We used...
Mercury methylation influenced by areas of past mercury mining in the Terlingua district, Southwest Texas, USA
J. E. Gray, M.E. Hines, H. Biester
2006, Applied Geochemistry (21) 1940-1954
Speciation and microbial transformation of Hg was studied in mine waste from abandoned Hg mines in SW Texas to evaluate the potential for methyl-Hg production and degradation in mine wastes. In mine waste samples, total Hg, ionic Hg2+, Hg0, methyl-Hg, organic C, and total S concentrations were measured, various Hg...
Concentration and dry deposition of mercury species in arid south central New Mexico (2001-2002)
Colleen A. Caldwell, Philip Swartzendruber, Eric Prestbo
2006, Environmental Science & Technology (40) 7535-7540
This research was initiated to characterize atmospheric deposition of reactive gaseous mercury (RGM), particulate mercury (HgP; <2.5 μm), and gaseous elemental mercury (Hg0) in the arid lands of south central New Mexico. Two methods were field-tested to estimate dry deposition of three mercury species. A manual speciation sampling train consisting...
Seismic characteristics of central Brazil crust and upper mantle: A deep seismic refraction study
J.E. Soares, J. Berrocal, R.A. Fuck, Thomas Mooney, D.B.R. Ventura
2006, Journal of Geophysical Research B: Solid Earth (111)
[1] A two‐dimensional model of the Brazilian central crust and upper mantle was obtained from the traveltime interpretation of deep seismic refraction data from the Porangatu and Cavalcante lines, each approximately 300 km long. When the lines were deployed, they overlapped by 50 km, forming an E‐W...
Consumers limit the abundance and dynamics of a perennial shrub with a seed bank
M. J. Kauffman, J.L. Maron
2006, American Naturalist (168) 454-470
For nearly 30 years, ecologists have argued that predators of seeds and seedlings seldom have population-level effects on plants with persistent seed banks and density-dependent seedling survival. We parameterized stage-based population models that incorporated density dependence and seed dormancy with data from a 5.5-year experiment that quantified how granivorous mice...
Mercury in soils, lakes, and fish in Voyageurs National Park (Minnesota): Importance of atmospheric deposition and ecosystem factors
J.G. Wiener, B.C. Knights, M.B. Sandheinrich, Jeffrey D. Jeremiason, M. E. Brigham, D.R. Engstrom, L. G. Woodruff, W.F. Cannon, S.J. Balogh
2006, Environmental Science & Technology (40) 6261-6268
Concentrations of methylmercury in game fish from many interior lakes in Voyageurs National Park (MN, U.S.A.) substantially exceed criteria for the protection of human health. We assessed the importance of atmospheric and geologic sources of mercury to interior lakes and watersheds within the Park and identified ecosystem factors associated with...
Age and duration of eclogite-facies metamorphism, North Qaidam HP/UHP terrane, Western China
C.G. Mattinson, J. L. Wooden, J. G. Liou, D.K. Bird, C.L. Wu
2006, American Journal of Science (306) 683-711
Amphibolite-facies para-and orthogneisses near Dulan, at the southeast end of the North Qaidam terrane, enclose minor eclogite and peridotite which record ultra-high pressure (UHP) metamorphism associated with the Early Paleozoic continental collision of the Qilian and Qaidam microplates. Field relations and coesite inclusions in zircons from paragneiss suggest that felsic,...
Shrinking ponds in subarctic Alaska based on 1950-2002 remotely sensed images
B. Riordan, D. Verbyla, A. D. McGuire
2006, Journal of Geophysical Research G: Biogeosciences (111)
Over the past 50 years, Alaska has experienced a warming climate with longer growing seasons, increased potential evapotranspiration, and permafrost warming. Research from the Seward Peninsula and Kenai Peninsula has demonstrated a substantial landscape-level trend in the reduction of surface water and number of closed-basin ponds. We investigated whether this...
Absolute calibration accuracy of L4 TM and L5 TM sensor image pairs
G. Chander, E. Micijevic
2006, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The Landsat suite of satellites has collected the longest continuous archive of multispectral data of any land-observing space program. From the Landsat program's inception in 1972 to the present, the Earth science user community has benefited from a historical record of remotely sensed data. However, little attention has been paid...
Distribution and abundance of American eels in the White Oak River estuary, North Carolina
J.E. Hightower, C. Nesnow
2006, Southeastern Naturalist (5) 693-710
Apparent widespread declines in abundance of Anguilla rostrata (American eel) have reinforced the need for information regarding its life history and status. We used commercial eel pots and crab (peeler) pots to examine the distribution, condition, and abundance of American eels within the White Oak River estuary, NC, during summers...
Geomorphic effects of large debris flows and flash floods, northern Venezuela, 1999
M. C. Larsen, G. F. Wieczorek
2006, Zeitschrift fur Geomorphologie, Supplementband (145) 147-175
A rare, high-magnitude storm in northern Venezuela in December 1999 triggered debris flows and flash floods, and caused one of the worst natural disasters in the recorded history of the Americas. Some 15,000 people were killed. The debris flows and floods inundated coastal communities on alluvial fans at the mouths...
Three-dimensional compressional wavespeed model, earthquake relocations, and focal mechanisms for the Parkfield, California, region
C. Thurber, H. Zhang, F. Waldhauser, J. Hardebeck, A. Michael, D. Eberhart-Phillips
2006, Bulletin of the Seismological Society of America (96)
We present a new three-dimensional (3D) compressional vvavespeed (V p) model for the Parkfield region, taking advantage of the recent seismicity associated with the 2003 San Simeon and 2004 Parkfield earthquake sequences to provide increased model resolution compared to the work of Eberhart-Phillips and Michael (1993) (EPM93). Taking the EPM93...
San Andreas fault geometry in the Parkfield, California, region
R.W. Simpson, M. Barall, J. Langbein, J.R. Murray, M. J. Rymer
2006, Bulletin of the Seismological Society of America (96)
In map view, aftershocks of the 2004 Parkfield earthquake lie along a line that forms a straighter connection between San Andreas fault segments north and south of the Parkfield reach than does the mapped trace of the fault itself. A straightedge laid on a geologic map of Central California reveals...
The use of artificial impoundments by two amphibian species in the Delaware Water Gap National Recreation Area
J.T. Julian, C.D. Snyder, J.A. Young
2006, Northeastern Naturalist (13) 459-468
We compared breeding activity of Ambystoma maculatum (Spotted Salamander) and Rana sylvatica (Wood Frog) in artificial impoundments to patterns in natural wetlands over a three-year period in the Delaware Water Gap National Recreation Area. Rana sylvatica were 5.6 times more likely to use natural bodies of water for breeding than...
Addition of simultaneous heat and solute transport and variable fluid viscosity to SEAWAT
D. Thorne, C.D. Langevin, M.C. Sukop
2006, Computers & Geosciences (32) 1758-1768
SEAWAT is a finite-difference computer code designed to simulate coupled variable-density ground water flow and solute transport. This paper describes a new version of SEAWAT that adds the ability to simultaneously model energy and solute transport. This is necessary for simulating the transport of heat and salinity in coastal aquifers...
Recorded earthquake responses from the integrated seismic monitoring network of the Atwood Building, Anchorage, Alaska
M. Çelebi
2006, Earthquake Spectra (22) 847-864
An integrated seismic monitoring system with a total of 53 channels of accelerometers is now operating in and at the nearby free-field site of the 20-story steel-framed Atwood Building in highly seismic Anchorage, Alaska. The building has a single-story basement and a reinforced concrete foundation without piles. The monitoring system...
Dietary calcein marking of brook trout, Atlantic salmon, yellow perch, and coho salmon scales
D. C. Honeyfield, C.S. Ostrowski, J.W. Fletcher, J.W. Mohler
2006, North American Journal of Fisheries Management (26) 431-437
Brook trout Salvelinus fontinalis, Atlantic salmon Salmo salar, coho salmon Oncorhynchus kisutch, and yellow perch Perca flavescens fed calcein for 5 d showed characteristic calcein scale marks 7-10 d postmarking. In fish fed 0.75 or 1.25 g of calcein per kilogram of feed, the percentage of fish that exhibited a...
Effects of increased feeding frequency on growth of hybrid bluegill in ponds
C.R. Sager, D.L. Winkelman
2006, North American Journal of Aquaculture (68) 313-316
Increased feeding frequency has been used in aquaculture to increase growth and food conversion efficiency, and recent laboratory studies have indicated that feeding frequency could be used to reduce the size variation within groups of hybrid bluegills (F1: male bluegill Lepomis macrochirus x female green sunfish L. cyanellus). Our experiment...
DNA damage and external lesions in brown bullheads (Ameiurus nebulosus) from contaminated habitats
X. Yang, J. Meier, L. Chang, M. Rowan, P. C. Baumann
2006, Environmental Toxicology and Chemistry (25) 3035-3038
The Comet assay was used to compare levels of DNA damage in brown bullheads (Ameiurus nebulosus) collected from three known contaminated locations, the Cuyahoga River (OH, USA), Ashtabula River (OH, USA; both tributaries to Lake Erie, USA), and Ashumet Pond (Cape Cod, MA, USA), with brown...
Association between wetland disturbance and biological attributes in floodplain wetlands
S. R. Chipps, D.E. Hubbard, K.B. Werlin, N.J. Haugerud, K.A. Powell, John Thompson, T. Johnson
2006, Wetlands (26) 497-508
We quantified the influence of agricultural activities on environmental and biological conditions of floodplain wetlands in the upper Missouri River basin. Seasonally-flooded wetlands were characterized as low impact (non-disturbed) or high impact (disturbed) based on local land use. Biological data collected from these wetlands were used to develop a wetland...
Spatial structure in the diet of imperial eagles Aquila heliaca in Kazakhstan
T.E. Katzner, E. A. Bragin, S.T. Knick, A.T. Smith
2006, Journal of Avian Biology (37) 594-600
We evaluated the relationship between spatial variability in prey and food habits of eastern imperial eagles Aquila heliaca at a 90,000 ha national nature reserve in north-central Kazakhstan. Eagle diet varied greatly within the population and the spatial structure of eagle diet within the population varied according to the scale...
Foreword: Understanding through modeling
C. Zheng, E. Poeter, M. Hill, J. Doherty
2006, Conference Paper, Ground Water
[No abstract available]...
