Predicting wetland plant community responses to proposed water-level-regulation plans for Lake Ontario: GIS-based modeling
D.A. Wilcox, Y. Xie
2007, Journal of Great Lakes Research (33) 751-773
Integrated, GIS-based, wetland predictive models were constructed to assist in predicting the responses of wetland plant communities to proposed new water-level regulation plans for Lake Ontario. The modeling exercise consisted of four major components: 1) building individual site wetland geometric models; 2) constructing generalized wetland geometric models representing specific types...
Local structuring factors of invertebrate communities in ephemeral freshwater rock pools and the influence of more permanent water bodies in the region
M. Jocque, T. Graham, L. Brendonck
2007, Hydrobiologia (592) 271-280
We used three isolated clusters of small ephemeral rock pools on a sandstone flat in Utah to test the importance of local structuring processes on aquatic invertebrate communities. In the three clusters we characterized all ephemeral rock pools (total: 27) for their morphometry, and monitored their water quality, hydrology and...
The relationship between circulating ecdysteroids and chela allometry in male tanner crabs: Evidence for a terminal molt in the genus Chionoecetes
S.L. Tamone, S. James Taggart, A.G. Andrews, Jennifer Mondragon, J.K. Nielsen
2007, Journal of Crustacean Biology (27) 635-642
Whether male Tanner crabs, Chionoecetes bairdi, undergo a terminal molt associated with a change in claw allometry has long been debated. We measured molting hormone levels in captured male C. bairdi to assess the potential for molting. We plotted a frequency histogram of chela height to carapace width ratios and...
Variation in northern bobwhite demography along two temporal scales
T.H. Folk, Randall R. Holmes, J. Barry Grand
2007, Population Ecology (49) 211-219
Quantification and understanding of demographic variation across intra- and inter-annual temporal scales can benefit from the development of theoretical models of evolution and applied conservation of species. We used long-term survey data for northern bobwhites (Colinus virginianus) collected at the northern and southern extent of its geographic range to develop...
A comparative analysis of polybrominated diphenyl ethers and polychlorinated biphenyls in southern sea otters that died of infectious diseases and noninfectious causes
K. Kannan, E. Perrota, N. J. Thomas, D.M. Aldous
2007, Archives of Environmental Contamination and Toxicology (53) 293-302
Southern sea otters (Enhydra lutris nereis) from the California coast continue to exhibit a slower population regrowth rate than the population in Alaska. Infectious diseases have been identified as a frequent cause of death. Infectious diseases caused by varied pathogens including bacteria, fungi, and parasites were suggestive of compromised immunological...
Non-volcanic tremor driven by large transient shear stresses
J.L. Rubinstein, J.E. Vidale, J. Gomberg, P. Bodin, K. C. Creager, S. D. Malone
2007, Nature (448) 579-582
Non-impulsive seismic radiation or 'tremor' has long been observed at volcanoes and more recently around subduction zones. Although the number of observations of non-volcanic tremor is steadily increasing, the causative mechanism remains unclear. Some have attributed non-volcanic tremor to the movement of fluids, while its coincidence with geodetically observed slow-slip...
Separation of copper, iron, and zinc from complex aqueous solutions for isotopic measurement
David M. Borrok, Richard B. Wanty, William I. Ridley, Ruth E. Wolf, Paul J. Lamothe, M. Adams
2007, Chemical Geology (242) 400-414
The measurement of Cu, Fe, and Zn isotopes in natural samples may provide valuable information about biogeochemical processes in the environment. However, the widespread application of stable Cu, Fe, and Zn isotope chemistry to natural water systems remains limited by our ability to efficiently separate these trace elements from...
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...
Eo-Ulrichian to Neo-Ulrichian views: The renaissance of "layer-cake stratigraphy"
Carlton E. Brett, P.I. McLaughlin, G.C. Baird
2007, Conference Paper, Stratigraphy
Classical notions of "layer-cake stratigraphy" have been denigrated as representing an antiquated "Neptunian" view of the geologic record with the American paleontologist-stratigrapher E.O. Ulrich vilified as its quintessential advocate. Some of the extreme "layer-cake" interpretations of E.O. Ulrich are demonstrably incorrect, especially where applied in marginal marine and terrestrial settings....
Imprint of oaks on nitrogen availability and δ15N in California grassland-savanna: A case of enhanced N inputs?
S.S. Perakis, C.H. Kellogg
2007, Plant Ecology (191) 209-220
Woody vegetation is distributed patchily in many arid and semi-arid ecosystems, where it is often associated with elevated nitrogen (N) pools and availability in islands of fertility. We measured N availability and δ15N in paired blue-oak versus annual grass dominated patches to characterize the causes and consequences of spatial variation...
Cultural diversity, economic development and societal instability
D. Nettle, J.B. Grace, M. Choisy, H.V. Cornell, J.-F. Guegan, M.E. Hochberg
2007, PLoS ONE (2)
Background. Social scientists have suggested that cultural diversity in a nation leads to societal instability. However, societal instability may be affected not only by within-nation on ?? diversity, but also diversity between a nation and its neighbours or ?? diversity. It is also necessary to distinguish different domains of diversity,...
Integrated geophysical survey in defining subsidence features on a golf course
J. Xia, R. D. Miller
2007, Journal of Geophysics and Engineering (4) 443-451
Subsidence was observed at several places on the Salina Municipal Golf Course in areas known to be built over a landfill in Salina, Kansas. High-resolution magnetic survey (???5400 m2), multi-channel electrical resistivity profiling (three 154 m lines) and microgravity profiling (23 gravity-station values) were performed on a subsidence site (Green...
The PRISM palaeoclimate reconstruction and Pliocene sea-surface temperature
H.J. Dowsett
Williams M.Haywood A.M.Gregory F.J.Schmidt D.N., editor(s)
2007, Geological Society Special Publication 459-480
In this paper, I present a summary of the Pliocene Research, Interpretation and Synoptic Mapping (PRISM) palaeoenvironmental reconstruction, with emphasis on its historical development and range of boundary condition datasets. Sea-surface temperature (SST), sea level, sea ice, land cover (vegetation and ice) and topography are discussed as well as many...
The distribution, occurrence and environmental effect of mercury in Chinese coals
Lingyun Zheng, Gaisheng Liu, C. L. Chou
2007, Science of the Total Environment (384) 374-383
Mercury (Hg) is a toxic, persistent, and globally distributed pollutant due to its characteristic properties such as low melting and boiling points, conversion between chemical forms and participation in biological cycles. During combustion mercury in coal is almost totally emitted to the atmosphere. With a huge amount of coal consumed,...
Neogene transpressional foreland basin development on the north side of the central alaska range, usibelli group and nenana gravel, tanana basin
K.D. Ridgway, E.E. Thoms, P.W. Layer, M.E. Lesh, J. M. White, S. V. Smith
2007, Special Paper of the Geological Society of America 507-547
Neogene strata of the Tanana basin provide a long-term record of a northwardpropagating, transpressional foreland-basin system related to regional shortening of the central Alaska Range and strike-slip displacement on the Denali fault system. These strata are ???2 km thick and have been deformed and exhumed in thrust faults that form...
Earlier famine warning possible using remote sensing and models
M.E. Brown, C.C. Funk, G. Galu, R. Choularton
2007, Eos, Transactions, American Geophysical Union (88) 381-382
[No abstract available]...
Hazard assessment of the Tidal Inlet landslide and potential subsequent tsunami, Glacier Bay National Park, Alaska
G. F. Wieczorek, E.L. Geist, R.J. Motyka, M. Jakob
2007, Landslides (4) 205-215
An unstable rock slump, estimated at 5 to 10 × 106 m3, lies perched above the northern shore of Tidal Inlet in Glacier Bay National Park, Alaska. This landslide mass has the potential to rapidly move into Tidal Inlet and generate large, long-period-impulse tsunami waves. Field and photographic examination...
Salt tectonics and shallow subseafloor fluid convection: Models of coupled fluid-heat-salt transport
A. Wilson, C. Ruppel
2007, Geofluids (7) 377-386
Thermohaline convection associated with salt domes has the potential to drive significant fluid flow and mass and heat transport in continental margins, but previous studies of fluid flow associated with salt structures have focused on continental settings or deep flow systems of importance to petroleum exploration. Motivated by recent geophysical...
Understanding shallow gas occurrences in the Gulf of Lions
Ana Garcia-Garcia, Tommaso Tesi, Daniel L. Orange, T. Lorenson, Stefano Miserocchi, L. Langone, I. Herbert, J. Dougherty
2007, Geo-Marine Letters (27) 143-154
New coring data have been acquired along the western Gulf of Lions showing anomalous concentrations of methane (up to 95,700 ppm) off the Rhône prodelta and the head of the southern canyons Lacaze-Duthiers and Cap de Creus. Sediment cores were acquired with box and kasten cores during...
Flux and age of dissolved organic carbon exported to the Arctic Ocean: A carbon isotopic study of the five largest arctic rivers
P.A. Raymond, J.W. McClelland, R.M. Holmes, A.V. Zhulidov, K. Mull, B. J. Peterson, Robert G. Striegl, G. R. Aiken, T.Y. Gurtovaya
2007, Global Biogeochemical Cycles (21)
The export and Δ14C-age of dissolved organic carbon (DOC) was determined for the Yenisey, Lena, Ob', Mackenzie, and Yukon rivers for 2004–2005. Concentrations of DOC elevate significantly with increasing discharge in these rivers, causing approximately 60% of the annual export to occur during a 2-month period following spring ice breakup....
Dating young geomorphic surfaces using age of colonizing Douglas fir in southwestern Washington and northwestern Oregon, USA
T.C. Pierson
2007, Earth Surface Processes and Landforms (32) 811-831
Dating of dynamic, young (<500 years) geomorphic landforms, particularly volcanofluvial features, requires higher precision than is possible with radiocarbon dating. Minimum ages of recently created landforms have long been obtained from tree-ring ages of the oldest trees growing on new surfaces. But to estimate the year of landform creation requires...
Probabilistic seismic demand analysis using advanced ground motion intensity measures
P. Tothong, N. Luco
2007, Earthquake Engineering and Structural Dynamics (36) 1837-1860
One of the objectives in performance-based earthquake engineering is to quantify the seismic reliability of a structure at a site. For that purpose, probabilistic seismic demand analysis (PSDA) is used as a tool to estimate the mean annual frequency of exceeding a specified value of a structural demand parameter (e.g....
Holocene sea-level oscillations and environmental changes on the Eastern Black Sea shelf
E.V. Ivanova, I.O. Murdmaa, A.L. Chepalyga, T. M. Cronin, I.V. Pasechnik, O.V. Levchenko, S. S. Howe, A.V. Manushkina, E.A. Platonova
2007, Palaeogeography, Palaeoclimatology, Palaeoecology (246) 228-259
A multi-proxy study of four sediment cores from the Eastern (Caucasian) Black Sea shelf revealed five transgressive-regressive cycles overprinted on the general trend of glacioeustatic sea-level rise during the last 11,000??14C yr. These cycles are well represented in micro-and macrofossil assemblages, sedimentation rates, and grain size variations. The oldest recovered...
230Th-U dating of surficial deposits using the ion microprobe (SHRIMP-RG): A microstratigraphic perspective
K. Maher, J. L. Wooden, J.B. Paces, D. M. Miller
2007, Quaternary International (166) 15-28
We used the sensitive high-resolution ion microprobe reverse-geometry (SHRIMP-RG) to date pedogenic opal using the 230Th–U system. Due to the high-spatial resolution of an ion microprobe (typically 30 μm), regions of pure opal within a sample can be targeted and detrital material can be avoided. In addition, because the technique is non-destructive,...
Mountaintop island age determines species richness of boreal mammals in the American Southwest
J.K. Frey, M.A. Bogan, Terry L. Yates
2007, Ecography (30) 231-240
Models that describe the mechanisms responsible for insular patterns of species richness include the equilibrium theory of island biogeography and the nonequilibrium vicariance model. The relative importance of dispersal or vicariance in structuring insular distribution patterns can be inferred from these models. Predictions of the alternative models were tested for...
