Beach morphology and change along the mixed grain-size delta of the dammed Elwha River, Washington
J.A. Warrick, D.A. George, G. Gelfenbaum, P. Ruggiero, G. M. Kaminsky, M. Beirne
2009, Geomorphology (111) 136-148
Sediment supply provides a fundamental control on the morphology of river deltas, and humans have significantly modified these supplies for centuries. Here we examine the effects of almost a century of sediment supply reduction from the damming of the Elwha River in Washington on shoreline position and beach morphology of...
Experimental alteration of artificial and natural impact melt rock from the Chesapeake Bay impact structure
J. Declercq, H. Dypvik, Per Aagaard, J. Jahren, R.E. Ferrell Jr., J. Wright Horton Jr.
2009, Special Paper of the Geological Society of America 559-569
The alteration or transformation of impact melt rock to clay minerals, particularly smectite, has been recognized in several impact structures (e.g., Ries, Chicxulub, Mj??lnir). We studied the experimental alteration of two natural impact melt rocks from suevite clasts that were recovered from drill cores into the Chesapeake Bay impact structure...
Recent faulting in the Gulf of Santa Catalina: San Diego to Dana Point
H. F. Ryan, M.R. Legg, J. E. Conrad, R. W. Sliter
2009, Special Paper of the Geological Society of America 291-315
We interpret seismic-reflection profiles to determine the location and offset mode of Quaternary offshore faults beneath the Gulf of Santa Catalina in the inner California Continental Borderland. These faults are primarily northwest-trending, right-lateral, strike-slip faults, and are in the offshore Rose Canyon-Newport-Inglewood, Coronado Bank, Palos Verdes, and San Diego Trough...
Antipredator responses by native mosquitofish to non-native cichlids: An examination of the role of prey naiveté
Jennifer S. Rehage, Katherine L. Dunlop, William F. Loftus
2009, Ethology (115) 1046-1056
The strong impact of non-native predators in aquatic systems is thought to relate to the evolutionary naiveté of prey. Due to isolation and limited dispersal, this naiveté may be relatively high in freshwater systems. In this study, we tested this notion by examining the antipredator response of native mosquitofish, Gambusia holbrooki, to...
The effects of fire on avian communities: Spatio-temporal attributes of the literature 19122003
A. Leidolf, J.A. Bissonette
2009, International Journal of Wildland Fire (18) 609-622
We reviewed the temporal, geographic, and biogeographic distribution, as well as relevant research and publication attributes, of 512 documents addressing the effects of fire on avian communities, to provide an assessment of the scope of this literature and recommendations for future research. We summarized relevant attributes of all documents to...
Rock slope stability analysis along the North Carolina section of the Blue Ridge Parkway: Using a geographic information system (GIS) to integrate site data and digital geologic maps
R.S. Latham, R.M. Wooten, B.L. Cattanach, C.E. Merschat, G.N. Bozdog
2009, Conference Paper, 43rd U.S. Rock Mechanics Symposium and 4th U.S.-Canada Rock Mechanics Symposium
In 2008, the North Carolina Geological Survey (NCGS) completed a five-year geologic and geohazards inventory of the 406-km long North Carolina segment of the Blue Ridge Parkway (BRP). The ArcGIS™ format deliverables for rock slopes include a slope movement and slope movement deposit database and maps...
Mathematical modelling of anisotropy of illite-rich shale
E.M. Chesnokov, D.K. Tiwary, I.O. Bayuk, M.A. Sparkman, R.L. Brown
2009, Conference Paper, Geophysical Journal International
The estimation of illite-rich shale anisotropy to account for the alignment of clays and gas- or brine-filled cracks is presented via mathematical modelling. Such estimation requires analysis to interpret the dominance of one effect over another. This knowledge can help to evaluate the permeability in the unconventional reservoir, stress orientation,...
A new numerical method for calculating extrema of received power for polarimetric SAR
Y. Zhang, Jiahua Zhang, Z. Lu, W. Gong
2009, IEEE Geoscience and Remote Sensing Letters (6) 666-670
A numerical method called cross-step iteration is proposed to calculate the maximal/minimal received power for polarized imagery based on a target's Kennaugh matrix. This method is much more efficient than the systematic method, which searches for the extrema of received power by varying the polarization ellipse angles of receiving and...
Incorporating uncertainty into the ranking of SPARROW model nutrient yields from Mississippi/Atchafalaya River basin watersheds
Dale M. Robertson, Gregory E. Schwarz, David A. Saad, Richard B. Alexander
2009, Journal of the American Water Resources Association (45) 534-549
Excessive loads of nutrients transported by tributary rivers have been linked to hypoxia in the Gulf of Mexico. Management efforts to reduce the hypoxic zone in the Gulf of Mexico and improve the water quality of rivers and streams could benefit from targeting nutrient reductions toward watersheds with the highest...
Volatile selenium flux from the great Salt Lake, Utah
X. Diaz, W.P. Johnson, W.A. Oliver, D. L. Naftz
2009, Environmental Science & Technology (43) 53-59
The removal mechanisms that govern Se concentrations in the Great Salt Lake are unknown despite this terminal lake being an avian habitat of hemispheric importance. However, the volatilization flux of Se from the Great Salt Lake has not been previously measured due to challenges of analysis in this hypersaline environment...
Implications of anthropogenic river stage fluctuations on mass transport in a valley fill aquifer
David F. Boutt, Brandon J. Fleming
2009, Water Resources Research (45)
In humid regions a strong coupling between surface water features and groundwater systems may exist. In these environments the exchange of water and solute depends primarily on the hydraulic gradient between the reservoirs. We hypothesize that daily changes in river stage associated with anthropogenic water releases (such as those from...
Landscape planning for agricultural nonpoint source pollution reduction III: Assessing phosphorus and sediment reduction potential
M.W. Diebel, J.T. Maxted, Dale M. Robertson, S. Han, M. J. Vander Zanden
2009, Environmental Management (43) 69-83
Riparian buffers have the potential to improve stream water quality in agricultural landscapes. This potential may vary in response to landscape characteristics such as soils, topography, land use, and human activities, including legacies of historical land management. We built a predictive model to estimate the sediment and phosphorus load reduction...
A formal framework for scenario development in support of environmental decision-making
M. Mahmoud, Yajing Liu, H. Hartmann, S. Stewart, T. Wagener, D. Semmens, R. Stewart, H. Gupta, D. Dominguez, F. Dominguez, D. Hulse, R. Letcher, Brenda Rashleigh, C. Smith, R. Street, J. Ticehurst, M. Twery, Delden H. van, R. Waldick, D. White, L. Winter
2009, Environmental Modelling and Software (24) 798-808
Scenarios are possible future states of the world that represent alternative plausible conditions under different assumptions. Often, scenarios are developed in a context relevant to stakeholders involved in their applications since the evaluation of scenario outcomes and implications can enhance decision-making activities. This paper reviews the state-of-the-art of scenario development...
Decline in bloater fecundity in Southern Lake Michigan after decline of Diporeia
D.B. Bunnell, S.R. David, C.P. Madenjian
2009, Journal of Great Lakes Research (35) 45-49
Population fecundity can vary through time, sometimes owing to changes in adult condition. Consideration of these fecundity changes can improve understanding of recruitment variation. Herein, we estimated fecundity of Lake Michigan bloater Coregonus hoyi during December 2005 and February 2006. Bloater recruitment has been highly variable from 1962 to present,...
Hydrodynamic modeling of tsunamis from the Currituck landslide
E.L. Geist, P.J. Lynett, J.D. Chaytor
2009, Marine Geology (264) 41-52
Tsunami generation from the Currituck landslide offshore North Carolina and propagation of waves toward the U.S. coastline are modeled based on recent geotechnical analysis of slide movement. A long and intermediate wave modeling package (COULWAVE) based on the non-linear Boussinesq equations are used to simulate the tsunami. This model includes...
Change in diel catchability of young-of-year yellow perch associated with establishment of dreissenid mussels
Martin A. Stapanian, Patrick M. Kocovsky, Jean V. Adams
2009, Freshwater Biology (54) 1593-1604
1. Non-native mussels have increased water clarity in many lakes and streams in North America and Europe. Diel variation in catchability of some fish species has been linked to visibility during survey trawls (used to measure escapement). 2. Water clarity increased in nearshore areas of western Lake Erie by the...
A prototype feature system for feature retrieval using relationships
J. Choi, E.L. Usery
2009, Cartography and Geographic Information Science (36) 331-345
Using a feature data model, geographic phenomena can be represented effectively by integrating space, theme, and time. This paper extends and implements a feature data model that supports query and visualization of geographic features using their non-spatial and temporal relationships. A prototype feature-oriented geographic information system (FOGIS) is then developed...
Interactive effects of fire, soil climate, and moss on CO2 fluxes in black spruce ecosystems of interior Alaska
Jonathan A. O’Donnell, Merritt R. Turetsky, Jennifer W. Harden, Kristen L. Manies, L.E. Pruett, Gordon Shetler, Jason C. Neff
2009, Ecosystems (12) 57-72
Fire is an important control on the carbon (C) balance of the boreal forest region. Here, we present findings from two complementary studies that examine how fire modifies soil organic matter properties, and how these modifications influence rates of decomposition and C exchange in black spruce (Picea mariana)...
In situ measurements of contributions to the global electrical circuit by a thunderstorm in southeastern Brazil
J.N. Thomas, R.H. Holzworth, M.P. McCarthy
2009, Atmospheric Research (91) 153-160
The global electrical circuit, which maintains a potential of about 280??kV between the earth and the ionosphere, is thought to be driven mainly by thunderstorms and lightning. However, very few in situ measurements of electrical current above thunderstorms have been successfully obtained. In this paper, we present dc to very...
Discriminating assimilants and decoupling deep- vs. shallow-level crystal records at Mount Adams using 238U-230Th disequilibria and Os isotopes
Brian R. Jicha, Clark M. Johnson, Wes Hildreth, Brian L. Beard, Garret L. Hart, Steven B. Shirey, Brad S. Singer
2009, Earth and Planetary Science Letters (277) 38-49
A suite of 23 basaltic to dacitic lavas erupted over the last 350 kyr from the Mount Adams volcanic field has been analyzed for U–Th isotope compositions to evaluate the roles of mantle versus crustal components during magma genesis. All of the lavas have (230Th/238U) > 1 and span a large range...
Tidal and flood signatures of settling particles in the Gaoping submarine canyon (SW Taiwan) revealed from radionuclide and flow measurements
C.-A. Huh, J.T. Liu, H.-L. Lin, J. P. Xu
2009, Marine Geology (267) 8-17
Sediment transport and sedimentation processes in the Gaoping submarine canyon were studied using sediment trap and current meter moorings deployed at a location during the winter (January-March) and the summer (July-September) months in 2008. At the end of each deployment, sediment cores were also collected from the canyon floor at...
Research on the middle-of-receiver-spread assumption of the MASW method
Y. Luo, J. Xia, J. Liu, Y. Xu, Q. Liu
2009, Soil Dynamics and Earthquake Engineering (29) 71-79
The multichannel analysis of surface wave (MASW) method has been effectively used to determine near-surface shear- (S-) wave velocity. Estimating the S-wave velocity profile from Rayleigh-wave measurements is straightforward. A three-step process is required to obtain S-wave velocity profiles: acquisition of a multiple number of multichannel records along a linear...
International year of planet earth 7. Oceans, submarine land-slides and consequent tsunamis in Canada
D. C. Mosher
2009, Geoscience Canada (36) 179-190
Canada has the longest coastline and largest continental margin of any nation in the World. As a result, it is more likely than other nations to experience marine geohazards such as submarine landslides and consequent tsunamis. Coastal landslides represent a specific threat because of their possible proximity to societal infrastructure...
Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield
M.C. Gabriel, R. Kolka, T. Wickman, E. Nater, Laurel G. Woodruff
2009, Science of the Total Environment (407) 4117-4126
The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow...
Distribution and postbreeding environmental relationships of Northern leopard frogs (Rana [Lithobates] pipiens) in Washington
S.S. Germaine, D.W. Hays
2009, Western North American Naturalist (69) 537-547
Northern leopard frogs (Rana [Lithobates] pipiens) are considered sensitive, threatened, or endangered in all western states and western Canadian provinces. Historically present in eastern Washington in 6 major river drainages, leopard frogs are now only known to occur at 2 localized areas in the Crab Creek drainage in Grant County....
