Spread dynamics of perennial pepperweed (Lepidium latifolium) in two seasonal wetland areas
Mark J. Renz, Scott J. Steinmaus, David S. Gilmer, Joseph M. DiTomaso
2012, Invasive Plant Science and Management (5) 57-68
Perennial pepperweed is an invasive plant that is expanding rapidly in several plant communities in the western United States. In California, perennial pepperweed has aggressively invaded seasonal wetlands, resulting in degradation of habitat quality. We evaluated the rate and dynamics of population spread, assessed the effect of disturbance on spread,...
An atlas of Mars sedimentary rocks as seen by HiRISE
Ross Beyer, Kathryn M. Stack, Jennifer L. Griffes, Ralph E. Milliken, Kenneth E. Herkenhoff, Shane Byrne, John W. Holt, John P. Grotzinger
John P. Grotzinger, Ralph E. Milliken, editor(s)
2012, Book chapter, Sedimentary geology of Mars
Images of distant and unknown places have long stimulated the imaginations of both explorers and scientists. The atlas of photographs collected during the Hayden (1872)expedition to the Yellowstone region was essential to its successful advocacy and selection in 1872 as America’s first national park. Photographer William...
Physical Climate Forces
S.J. Williams, D. Atkinson, A. R. Byrd, H. Eicken, T. M. Hall, Thomas G. Huntington, Y. Kim, T.R. Knutson, J.P. Kossin, M. Lilly, J. M. Marra, J Obeysekera, A. Parris, J. Ratcliff, T. Ravens, D. Resio, P. Ruggiero, E. Robert Thieler, James G. Titus, T.V. Wamsley
2012, Book chapter, Coastal Impacts, Adaptation and Vulnerability: A Technical Input to the 2012 National Climate Assessment. Cooperative Report to the 2013 National Climate Assessment
Key FindingsThe coasts of the U.S. are home to many large urban centers and important infrastructure such seaports, airports, transportation routes, oil import and refining facilities, power plants, and military bases. All are vulnerable to varying degrees to impacts of global warming such as sea-level rise, storms, and flooding. High Confidence.Physical observations collected...
A catalog of Louisiana's nesting seabird colonies
William R. Fontenot, Steve W. Cardiff, Richard A. DeMay, Donna L. Dittmann, Stephen B. Hartley, Clinton W. Jeske, Nicole Lorenz, Thomas C. Michot, Robert Dan Purrington, Michael A. Seymour, William G. Vermillion
2012, Barataria-Terrebonne National Estuary Program Report 34
Summarizing his colonial nesting waterbird survey experiences along the northern coast of the Gulf of Mexico in a paper presented to the Colonial Waterbird Group of the Waterbird Society (Portnoy 1978), bird biologist John W. Portnoy stated, “This huge concentration of nesting waterbirds, restricted almost entirely to the wetlands and...
Developing a national stream morphology data exchange: needs, challenges, and opportunities
Mathias J. Collins, John R. Gray, Marie C. Peppler, Faith A. Fitzpatrick, Joseph P. Schubauer-Berigan
2012, Eos, Transactions, American Geophysical Union (93) 195
Stream morphology data, primarily consisting of channel and foodplain geometry and bed material size measurements, historically have had a wide range of applications and uses including culvert/ bridge design, rainfall- runoff modeling, food inundation mapping (e.g., U.S. Federal Emergency Management Agency food insurance studies), climate change studies, channel stability/sediment source...
The 2011 Virginia earthquake: what are scientists learning?
J. Wright Horton Jr., Robert A. Williams
2012, Eos, Transactions, American Geophysical Union (93) 317-318
Nearly 1 year ago, on 23 August, tens of millions of people in the eastern United States and southeastern Canada were startled in the middle of their workday (1:51 P.M. local time) by the sudden onset of moderate to strong ground shaking from a rare magnitude (M) 5.8 earthquake in...
Social.Water - A crowdsourcing tool for environmental data acquisition
Michael N. Fienen, Christopher Lowry
2012, Computers & Geosciences (49) 164-169
Remote telemetry has a long history of use for collection of environmental measurements. With the rise of mobile phones and SMS text-messaging capacity, many members of the general pubic carry communications equipment in their pockets at all times. Enabling the general public to provide environmental data through text messages has...
Varying sediment sources (Hudson Strait, Cumberland Sound, Baffin Bay) to the NW Labrador Sea slope between and during Heinrich events 0 to 4
John T. Andrews, D.C. Barber, A. E. Jennings, D. D. Eberl, B. Maclean, M.E. Kirby, J.S. Stoner
2012, Journal of Quaternary Science (27) 475-484
Core HU97048-007PC was recovered from the continental Labrador Sea slope at a water depth of 945 m, 250 km seaward from the mouth of Cumberland Sound, and 400 km north of Hudson Strait. Cumberland Sound is a structural trough partly floored by Cretaceous mudstones and Paleozoic carbonates. The record extends from ∼10 to...
Formation of replicating saponite from a gel in the presence of oxalate: implications for the formation of clay minerals in carbonaceous chondrites and the origin of life
Dirk Schumann, Hyman Hartman, Dennis D. Eberl, S. Kelly Sears, Reinhard Hesse, Hojatollah Vali
2012, Astrobiology (12) 549-561
The potential role of clay minerals in the abiotic origin of life has been the subject of ongoing debate for the past several decades. At issue are the clay minerals found in a class of meteorites known as carbonaceous chondrites. These clay minerals are the product of aqueous alteration of...
Peralkaline- and calc-alkaline-hosted volcanogenic massive sulfide deposits of the Bonnifield District, East-Central Alaska
Cynthia Dusel-Bacon, Nora K. Foley, John E. Slack, Alan E. Koenig, Robert L. Oscarson
2012, Economic Geology (107) 1403-1432
Volcanogenic massive sulfide (VMS) Zn-Pb-Cu-Ag-Au deposits of the Bonnifield mining district formed during Late Devonian-Early Mississippian magmatism along the western edge of Laurentia. The largest deposits, Dry Creek and WTF, have a combined resource of 5.7 million tonnes at 10% Zn, 4% Pb, 0.3% Cu, 300 grams per tonne (g/t)...
Distribution of arsenic, selenium, and other trace elements in high pyrite Appalachian coals: evidence for multiple episodes of pyrite formation
S. F. Diehl, M. B. Goldhaber, A.E. Koenig, H.A. Lowers, L.F. Ruppert
2012, International Journal of Coal Geology (94) 238-249
Pennsylvanian coals in the Appalachian Basin host pyrite that is locally enriched in potentially toxic trace elements such as As, Se, Hg, Pb, and Ni. A comparison of pyrite-rich coals from northwestern Alabama, eastern Kentucky, and West Virginia reveals differences in concentrations and mode of occurrence of trace elements in...
Holocene seasonal variability inferred from multiple proxy records from Crevice Lake, Yellowstone National Park, USA
Cathy Whitlock, Walter E. Dean, Sherilyn C. Fritz, Lora R. Stevens, Jeffery R. Stone, Mitchell J. Power, Joseph R. Rosenbaum, Kenneth L. Pierce, Brandi B. Bracht-Flyr
2012, Palaeogeography, Palaeoclimatology, Palaeoecology (331-332) 90-103
A 9400-yr-old record from Crevice Lake, a semi-closed alkaline lake in northern Yellowstone National Park, was analyzed for pollen, charcoal, geochemistry, mineralogy, diatoms, and stable isotopes to develop a nuanced understanding of Holocene environmental history in a region of northern Rocky Mountains that receives both summer and winter precipitation. The...
Distribution of potentially bioavailable natural organic carbon in aquifer sediments at a chloroethene-contaminated site
L.K. Thomas, M.A. Widdowson, F. H. Chapelle, J.T. Novak, J.E. Boncal, C. A. Lebron
2012, Journal of Environmental Engineering (139) 54-60
The distribution of natural organic carbon was investigated at a chloroethene-contaminated site where complete reductive dechlorination of tetrachloroethene (PCE) to vinyl chloride and ethene was observed. In this study, operationally defined potentially bioavailable organic carbon (PBOC) was measured in surficial aquifer sediment samples collected at varying depths and locations in...
Potentially bioavailable natural organic carbon and hydrolyzable amino acids in aquifer sediments
Lashun K. Thomas, Mark A. Widdowson, John T. Novak, Francis H. Chapelle, Ronald Benner, Karl Kaiser
2012, Ground Water Monitoring and Remediation (32) 92-95
This study evaluated the relationship between concentrations of operationally defined potentially bioavailable organic -carbon (PBOC) and hydrolyzable amino acids (HAAs) in sediments collected from a diverse range of chloroethene--contaminated sites. Concentrations of PBOC and HAA were measured using aquifer sediment samples collected at six selected study sites. Average concentrations of...
Pioneer of herpetology at His Century Mark: Hobart M. Smith
R. Bruce Bury, Stanley E. Trauth
2012, Herpetological Conservation and Biology (7) vii-viii
No abstract available....
Avoiding potential conflicts: editors publishing in HCB
R. Bruce Bury
2012, Herpetological Conservation and Biology (7) iii-iv
No abstract available....
Changing some of the guard at Herpetological Conservation and Biology
R. Bruce Bury
2012, Herpetological Conservation and Biology (7) v
No abstract available....
The first direct evidence of pre-columbian sources of palygorskite for Maya Blue
Dean E. Arnold, Bruce F. Bohor, Hector Neff, Gary M. Feinman, Patrick Ryan Williams, Laure Dussubieux, Ronald Bishop
2012, Journal of Archaeological Science (39) 2252-2260
Maya Blue, a nano-structured clay–organic complex of palygorskite and indigo, was used predominantly before the Spanish Conquest. It has fascinated chemists, material scientists, archaeologists and art historians for decades because it is resistant to the effect of acids, alkalis, and other reagents, and its rich color has persisted for centuries...
Structure and mechanism of diet specialisation: testing models of individual variation in resource use with sea otters
M. Tim Tinker, Paulo R. Guimaraes Jr., Mark Novak, Flavia Maria Darcie Marquitti, James L. Bodkin, Michelle Staedler, Gena B. Bentall, James A. Estes
2012, Ecology Letters (15) 475-483
Studies of consumer-resource interactions suggest that individual diet specialisation is empirically widespread and theoretically important to the organisation and dynamics of populations and communities. We used weighted networks to analyze the resource use by sea otters, testing three alternative models for how individual diet specialisation may arise. As expected, individual...
Reply to Blaauw et al., Boslough, Daulton, Gill et al., and Hardiman et al.: Younger Dryas impact proxies in Lake Cuitzeo, Mexico
I. Israde-Alcántara, J. L. Bischoff, P.S. DeCarli, G. Domínguez-Vázquez, T.E. Bunch, R.B. Firestone, J.P. Kennett, A. West
2012, Proceedings of the National Academy of Sciences of the United States of America (109) E2245-E2247
No abstract available....
Very high-temperature impact melt products as evidence for cosmic airbursts and impacts 12,900 years ago
Ted E. Bunch, Robert E. Hermes, Andrew Moore, Douglas J. Kennett, James C. Weaver, James H. Wittke, Paul S. DeCarli, James L. Bischoff, Gordon C. Hillman, George A. Howard, David R. Kimbel, Gunther Kletetschka, Carl P. Lipo, Sachiko Sakai, Zsolt Revay, Allen West, Richard B. Firestone, James P. Kennett
2012, Proceedings of the National Academy of Sciences of the United States of America (109) E1903-E1912
It has been proposed that fragments of an asteroid or comet impacted Earth, deposited silica-and iron-rich microspherules and other proxies across several continents, and triggered the Younger Dryas cooling episode 12,900 years ago. Although many independent groups have confirmed the impact evidence, the hypothesis remains controversial because some groups have...
Paleoseismic and geomorphologic evidence of recent tectonic activity of the Pozohondo Fault (Betic Cordillera, SE Spain)
M.A. Rodriguez-Pascua, R. Perez-Lopez, V.H. Garduño-Monroy, J. L. Giner-Robles, P.G. Silva, M.A. Perucha-Atienza, V.M. Hernandez-Madrigal, J. Bischoff
2012, Journal of Iberian Geology (38) 255-267
Instrumental and historical seismicity in the Albacete province (External Prebetic Zone) has been scarcely recorded. However, major strike-slip faults showing NW-SE trending provide geomorphologic and paleoseismic evidence of recent tectonic activity (Late Pleistocene to Present). Moreover, these faults are consistently well oriented under the present stress tensor and therefore, they...
A multiproxy reconstruction of the palaeoenvironment and palaeoclimate of the Late Pleistocene in northeastern Iberia: Cova dels Xaragalls, Vimbodí-Poblet, Paratge Natural de Poblet, Catalonia
Juan Manuel Lopez-Garcia, Hugues-Alexandre Blain, Maria Bennasar, Itxaso Euba, Sandra Banuls, James Bischoff, Esther Lopez-Ortega, Palmira Saladie, Paloma Uzquiano, Josep Vallverdu
2012, Boreas (41) 235-249
The Cova dels Xaragalls is a small open karst system, located in the municipality of Vimbodí-Poblet (Tarragona, Catalonia, NE Spain). It is an important Holocene archaeological site that was inspected in the 1970s but from which little has been published. New excavations starting in 2008 have exposed a deep Late...
Evidence from central Mexico supporting the Younger Dryas extraterrestrial impact hypothesis
Isabel Israde-Alcántara, James L. Bischoff, Gabriela Dominguez-Vazquez, Hong-Chun Li, Paul S. DeCarli, Ted E. Bunch, James H. Wittke, James C. Weaver, Richard B. Firestone, Allen West, James P. Kennett, Chris Mercer, Sujing Xie, Eric K. Richman, Charles R. Kinzie, Wendy S. Wolbach
Steven M. Stanley, editor(s)
2012, Proceedings of the National Academy of Sciences of the United States of America (109) E738-E747
We report the discovery in Lake Cuitzeo in central Mexico of a black, carbon-rich, lacustrine layer, containing nanodiamonds, microspherules, and other unusual materials that date to the early Younger Dryas and are interpreted to result from an extraterrestrial impact. These proxies were found in a 27-m-long core as part of...
Introduction: CRevolution 2: origin and evolution of the Colorado River System II
Karl E. Karlstrom, L. Sue Beard, Kyle House, Richard A. Young, Andres Aslan, George Billingsley, Joel Pederson
2012, Geosphere (8) 1170-1176
A 2010 Colorado River symposium held in Flagstaff, Arizona, in May 2010, had 70 participants who engaged in intense debate about the origin and evolution of the Colorado River system. This symposium, built on two previous decadal scientific meetings, focused on forging scientific consensus where possible, while also articulating continued...
