Subsurface control on seafloor erosional processes offshore of the Chandeleur Islands, Louisiana
David Twichell, Elizabeth A. Pendleton, Wayne E. Baldwin, James G. Flocks
2009, Geo-Marine Letters (29) 349-358
The Chandeleur Islands lie on the eastern side of the modern Mississippi River delta plain, near the edge of the St. Bernard Delta complex. Since abandonment approximately 2,000 years b.p., this delta complex has undergone subsidence and ravinement as the shoreline has transgressed across it. High-resolution seismic-reflection, sidescan-sonar, and...
Expansion of Dreissena into offshore waters of Lake Michigan and potential impacts on fish populations
D.B. Bunnell, C.P. Madenjian, J.D. Holuszko, J.V. Adams, J. R. P. French III
2009, Journal of Great Lakes Research (35) 74-80
Lake Michigan was invaded by zebra mussels (Dreissena polymorpha) in the late 1980s and then followed by quagga mussels (D. bugensis) around 1997. Through 2000, both species (herein Dreissena) were largely restricted to depths less than 50??m. Herein, we provide results of an annual lake-wide bottom trawl survey in Lake...
Nature versus nurture: functional assessment of restoration effects on wetland services using Nuclear Magnetic Resonance Spectroscopy
P.V. Sundareshwar, C.J. Richardson, R.A. Gleason, P.J. Pellechia, S. Honomichl
2009, Geophysical Research Letters (36)
Land-use change has altered the ability of wetlands to provide vital services such as nutrient retention. While compensatory practices attempt to restore degraded wetlands and their functions, it is difficult to evaluate the recovery of soil biogeochemical functions that are critical for restoration of ecosystem services. Using solution 31P Nuclear...
Emsian (late Early Devonian) sponges from west-central and south-central Alaska
J.K. Rigby, R. B. Blodgett, N.K. Anderson
2009, Journal of Paleontology (83) 293-298
Relatively common specimens of the hypercalcified agelasiid sponge Hormospongia labyrinthica Rigby and Blodgett, 1983 and specimens of associated species of Hormospongia have been previously reported from Emsian and Eifelian stratigraphic units at several localities in south-central and southeastern Alaska (Rigby and Blodgett, 1983). Those sponges were first described from the...
TandEM: Titan and Enceladus mission
A. Coustenis, S.K. Atreya, T. Balint, R. H. Brown, M.K. Dougherty, F. Ferri, M. Fulchignoni, D. Gautier, R.A. Gowen, C.A. Griffith, L.I. Gurvits, R. Jaumann, Y. Langevin, M.R. Leese, J. I. Lunine, C.P. McKay, X. Moussas, I. Muller-Wodarg, F. Neubauer, T.C. Owen, F. Raulin, E.C. Sittler, F. Sohl, Christophe Sotin, G. Tobie, T. Tokano, E. P. Turtle, J.-E. Wahlund, J.H. Waite, K. H. Baines, J. E. Blamont, A.J. Coates, I. Dandouras, T. Krimigis, E. Lellouch, R. D. Lorenz, A. Morse, C.C. Porco, M. Hirtzig, J. Saur, T. Spilker, J.C. Zarnecki, E. Choi, N. Achilleos, R. Amils, P. Annan, D.H. Atkinson, Y. Benilan, C. Bertucci, B. Bezard, G.L. Bjoraker, M. Blanc, L. Boireau, J. Bouman, M. Cabane, M.T. Capria, E. Chassefiere, P. Coll, M. Combes, J.F. Cooper, A. Coradini, F. Crary, T. Cravens, I.A. Daglis, E. de Angelis, C. De Bergh, I. de Pater, C. Dunford, G. Durry, O. Dutuit, D. Fairbrother, F.M. Flasar, A.D. Fortes, R. Frampton, M. Fujimoto, M. Galand, O. Grasset, M. Grott, T. Haltigin, A. Herique, F. Hersant, H. Hussmann, W. Ip, R. Johnson, E. Kallio, S. Kempf, M. Knapmeyer, W. Kofman, R. Koop, T. Kostiuk, N. Krupp, M. Kuppers, H. Lammer, L.-M. Lara, P. Lavvas, Stéphane Le Mouélic, S. Lebonnois, S. Ledvina, Ji Li, T.A. Livengood, R.M. Lopes, J. #NAME? Lopez-Moreno, D. Luz, P.R. Mahaffy, U. Mall, J. Martinez-Frias, B. Marty, T. McCord, C.M. Salvan, A. Milillo, D.G. Mitchell, R. Modolo, O. Mousis, M. Nakamura, Catherine D. Neish, C.A. Nixon, D.N. Mvondo, G. Orton, M. Paetzold, J. Pitman, S. Pogrebenko, W. Pollard, O. Prieto-Ballesteros, P. Rannou, K. Reh, L. Richter, F.T. Robb, R. Rodrigo, S. Rodriguez, P. Romani, M.R. Bermejo, E.T. Sarris, P. Schenk, B. Schmitt, N. Schmitz, D. Schulze-Makuch, K. Schwingenschuh, A. Selig, B. Sicardy, L. Soderblom, L.J. Spilker, D. Stam, A. Steele, K. Stephan, D.F. Strobel, K. Szego, Szopa
2009, Experimental Astronomy (23) 893-946
TandEM was proposed as an L-class (large) mission in response to ESA’s Cosmic Vision 2015–2025 Call, and accepted for further studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds tied together by location and properties, whose remarkable natures...
Diets of aquatic birds reflect changes in the Lake Huron ecosystem
Craig E. Hebert, D.V. Chip Weseloh, Abode Idrissi, Michael T. Arts, Edward F. Roseman
2009, Aquatic Ecosystem Health & Management (12) 37-44
Human activities have affected the Lake Huron ecosystem, in part, through alterations in the structure and function of its food webs. Insights into the nature of food web change and its ecological ramifications can be obtained through the monitoring of high trophic level predators such as aquatic birds. Often, food...
Long-term changes in quiescent degassing at Mount Baker Volcano, Washington, USA; Evidence for a stalled intrusion in 1975 and connection to a deep magma source
Cynthia A. Werner, William C. Evans, Michael P. Poland, Michael P. Doukas, D.S. Tucker
2009, Journal of Volcanology and Geothermal Research (186) 379-386
Long-term changes have occurred in the chemistry, isotopic ratios, and emission rates of gas at Mount Baker volcano following a major thermal perturbation in 1975. In mid-1975 a large pulse in sulfur and carbon dioxide output was observed both in emission rates and in fumarole samples. Emission rates of CO2...
Great Lakes prey fish populations: A cross-basin overview of status and trends in 2008
Owen T. Gorman, David B. Bunnell
2009, Conference Paper
Assessments of prey fishes in the Great Lakes have been conducted annually since the 1970s by the Great Lakes Science Center, sometimes assisted by partner agencies. Prey fish assessments differ among lakes in the proportion of a lake covered, seasonal timing, bottom trawl gear used, sampling design, and the manner...
A case of timely satellite image acquisitions in support of coastal emergency environmental response management
Elijah W. Ramsey III, Dirk Werle, Zhong Lu, Amina Rangoonwala, Yukihiro Suzuoki
2009, Journal of Coastal Research (25) 1168-1172
The synergistic application of optical and radar satellite imagery improves emergency response and advance coastal monitoring from the realm of “opportunistic” to that of “strategic.” As illustrated by the Hurricane Ike example, synthetic aperture radar imaging capabilities are clearly applicable for emergency response operations, but they are also relevant to...
Preparing a population for an earthquake like Chi-Chi: The Great Southern California ShakeOut
Lucile M. Jones, The ShakeOut Team
2009, Conference Paper, Improving earthquake mitigation through innovations and applications in seismic science, engineering, communication, and response, Proceedings of a U.S.-Iran seismic workshop
The Great Southern California ShakeOut was a week of special events featuring the largest earthquake drill in United States history. On November 13, 2008, over 5 million southern Californians pretended that a magnitude-7.8 earthquake had occurred and practiced actions that could reduce its impact on their lives. The primary message...
Status and trends of the Lake Huron deepwater demersal fish ommunity, 2008
Edward F. Roseman, Timothy P. O’Brien, Stephen C. Riley, Steve A. Farha, John R. French
2009, Conference Paper
The U.S.Geological Survey Great Lakes Science Center has conducted trawl surveys to assess annual changes in the deepwater demersal fish community of Lake Huron since 1973. Since 1992, surveys have been carried out using a 21 m wing trawl towed on-contour at depths ranging from 9 to 110 m on...
Paleoenvironmental recovery from the Chesapeake Bay bolide impact: The benthic foraminiferal record
C. W. Poag
2009, Special Paper of the Geological Society of America 747-773
The late Eocene Chesapeake Bay bolide impact transformed its offshore target site from an outer neritic, mid-shelf seafloor into a bathyal crater basin. To obtain a depositional record from one of the deepest parts of this basin, the U.S. Geological Survey (USGS) and the International Continental Scientific Drilling Program (ICDP)...
Geomorphic controls on mercury accumulation in soils from a historically mined watershed, Central California Coast Range, USA
J.M. Holloway, M. B. Goldhaber, J.M. Morrison
2009, Applied Geochemistry (24) 1538-1548
Historic Hg mining in the Cache Creek watershed in the Central California Coast Range has contributed to the downstream transport of Hg to the San Francisco Bay-Delta. Different aspects of Hg mobilization in soils, including pedogenesis, fluvial redistribution of sediment, volatilization and eolian transport were considered. The greatest soil concentrations...
Intercomparison, interpretation, and assessment of spring phenology in North America estimated from remote sensing for 1982-2006
M.A. White, K. M. de Beurs, K. Didan, D.W. Inouye, A.D. Richardson, O.P. Jensen, J. O'Keefe, G. Zhang, R.R. Nemani, Leeuwen W.J.D. van W.J.D., Jesslyn F. Brown, A. de Wit, M. Schaepman, X. Lin, M. Dettinger, A.S. Bailey, J. Kimball, M.D. Schwartz, D. D. Baldocchi, J.T. Lee, W.K. Lauenroth
2009, Global Change Biology (15) 2335-2359
Shifts in the timing of spring phenology are a central feature of global change research. Long-term observations of plant phenology have been used to track vegetation responses to climate variability but are often limited to particular species and locations and may not represent synoptic patterns. Satellite remote sensing is instead...
Effect of time dependence on probabilistic seismic-hazard maps and deaggregation for the central Apennines, Italy
A. Akinci, F. Galadini, D. Pantosti, Mark D. Petersen, L. Malagnini, D. Perkins
2009, Bulletin of the Seismological Society of America (99) 585-610
We produce probabilistic seismic-hazard assessments for the central Apennines, Italy, using time-dependent models that are characterized using a Brownian passage time recurrence model. Using aperiodicity parameters, ?? of 0.3, 0.5, and 0.7, we examine the sensitivity of the probabilistic ground motion and its deaggregation to these parameters. For the seismic...
Estimating 3D variation in active-layer thickness beneath arctic streams using ground-penetrating radar
T.R. Brosten, J.H. Bradford, J. P. McNamara, M.N. Gooseff, J.P. Zarnetske, W.B. Bowden, M.E. Johnston
2009, Journal of Hydrology (373) 479-486
We acquired three-dimensional (3D) ground-penetrating radar (GPR) data across three stream sites on the North Slope, AK, in August 2005, to investigate the dependence of thaw depth on channel morphology. Data were migrated with mean velocities derived from multi-offset GPR profiles collected across a stream section within each of the...
Estimating avian population size using Bowden's estimator
Duane R. Diefenbach
2009, The Auk (126) 211-217
Avian researchers often uniquely mark birds, and multiple estimators could be used to estimate population size using individually identified birds. However, most estimators of population size require that all sightings of marked birds be uniquely identified, and many assume homogeneous detection probabilities. Bowden's estimator can incorporate sightings of marked birds...
The 2007 southern California wildfires: Lessons in complexity
Jon E. Keeley, H. Safford, C. J. Fotheringham, J. Franklin, M. Moritz
2009, Journal of Forestry (107) 287-296
The 2007 wildfire season in southern California burned over 1,000,000 ac (∼400,000 ha) and included several megafires. We use the 2007 fires as a case study to draw three major lessons about wildfires and wildfire complexity in southern California. First, the great majority of large fires in southern California occur...
On selecting a prior for the precision parameter of Dirichlet process mixture models
R.M. Dorazio
2009, Journal of Statistical Planning and Inference (139) 3384-3390
In hierarchical mixture models the Dirichlet process is used to specify latent patterns of heterogeneity, particularly when the distribution of latent parameters is thought to be clustered (multimodal). The parameters of a Dirichlet process include a precision parameter ?? and a base probability measure G0. In problems where ?? is...
Predicting dietborne metal toxicity from metal influxes
M.-N. Croteau, S. N. Luoma
2009, Environmental Science & Technology (43) 4915-4921
Dietborne metal uptake prevails for many species in nature. However, the links between dietary metal exposure and toxicity are not well understood. Sources of uncertainty include the lack of suitable tracers to quantify exposure for metals such as copper, the difficulty to assess dietary processes such as food ingestion rate,...
Interactions between soil thermal and hydrological dynamics in the response of Alaska ecosystems to fire disturbance
Shuhua Yi, A. David McGuire, Jennifer Harden, Eric Kasischke, Kristen L. Manies, Larry Hinzman, Anna K. Liljedahl, J. Randerson, Heping Liu, Vladimir E. Romanovsky, Sergey S. Marchenko, Yongwon Kim
2009, Journal of Geophysical Research: Biogeosciences (114)
Soil temperature and moisture are important factors that control many ecosystem processes. However, interactions between soil thermal and hydrological processes are not adequately understood in cold regions, where the frozen soil, fire disturbance, and soil drainage play important roles in controlling interactions among these processes. These interactions were investigated with...
Females increase reproductive investment in response to helper-mediated improvements in allo-feeding, nest survival, nestling provisioning and post-fledging survival in the Karoo scrub-robin Cercotrichas coryphaeus
P. Lloyd, Taylor W. Andrew, Morne A. du Plessis, T. E. Martin
2009, Journal of Avian Biology (40) 400-411
In many cooperatively-breeding species, the presence of one or more helpers improves the reproductive performance of the breeding pair receiving help. Helper contributions can take many different forms, including allo-feeding, offspring provisioning, and offspring guarding or defence. Yet, most studies have focussed on single forms of helper contribution, particularly offspring...
Structural controls on fractured coal reservoirs in the southern Appalachian Black Warrior foreland basin
R.H. Groshong Jr., J.C. Pashin, M.R. McIntyre
2009, Journal of Structural Geology (31) 874-886
Coal is a nearly impermeable rock type for which the production of fluids requires the presence of open fractures. Basin-wide controls on the fractured coal reservoirs of the Black Warrior foreland basin are demonstrated by the variability of maximum production rates from coalbed methane wells. Reservoir behavior depends on distance...
Assessment of diel chemical and isotopic techniques to investigate biogeochemical cycles in the upper Klamath River, Oregon, USA
S.R. Poulson, A.B. Sullivan
2009, Chemical Geology (266) 114-122
The upper Klamath River experiences a cyanobacterial algal bloom and poor water quality during the summer. Diel chemical and isotopic techniques have been employed in order to investigate the rates of biogeochemical processes. Four diel measurements of field parameters (temperature, pH, dissolved oxygen concentrations, and alkalinity) and stable isotope compositions...
Louisiana wetland water level monitoring using retracked TOPEX/POSEIDON altimetry
H. Lee, C. K. Shum, Y. Yi, M. Ibaraki, J.-W. Kim, Andreas Braun, C.-Y. Kuo, Z. Lu
2009, Marine Geodesy (32) 284-302
Previous studies using satellite radar altimetry to observe inland river and wetland water level changes usually spatially average high-rate (10-Hz for TOPEX, 18-Hz for Envisat) measurements. Here we develop a technique to apply retracking of TOPEX waveforms by optimizing the estimated retracked gate positions using the Offset Center of Gravity...
