Morphological and chemical evidence of stromatolitic deposits in the 2.75 Ga Carajás banded iron formation, Brazil
Beatriz Ribeiro da Luz, James K. Crowley
2012, Earth and Planetary Science Letters (355-356) 60-72
We describe evidence of biogenicity in the morphology and carbon content of well-preserved, Neoarchean samples of banded iron formation (BIF) from Carajás, Brazil. Silica-rich BIF layers contain translucent ellipsoidal or trapezoidal structures (∼5–10 μm diameter) composed of silica, hematite, and kerogen, which are arranged in larger ring-like forms (rosettes). Stable...
A comparison among observations and earthquake simulator results for the allcal2 California fault model
Terry. E. Tullis, Keith B. Richards-Dinger, Michael Barall, James H. Dieterich, Edward H. Field, Eric M. Heien, Louise Kellogg, Fred F. Pollitz, John B. Rundle, Michael K. Sachs, Donald L. Turcotte, Steven N. Ward, M. Burak Yikilmaz
2012, Seismological Research Letters (83) 994-1006
In order to understand earthquake hazards we would ideally have a statistical description of earthquakes for tens of thousands of years. Unfortunately the ∼100‐year instrumental, several 100‐year historical, and few 1000‐year paleoseismological records are woefully inadequate to provide a statistically significant record. Physics‐based earthquake simulators can generate arbitrarily long...
Regional regression models of watershed suspended-sediment discharge for the eastern United States
David C. Roman, Richard M. Vogel, Gregory E. Schwarz
2012, Journal of Hydrologic Engineering (472-4723) 53-62
Estimates of mean annual watershed sediment discharge, derived from long-term measurements of suspended-sediment concentration and streamflow, often are not available at locations of interest. The goal of this study was to develop multivariate regression models to enable prediction of mean annual suspended-sediment discharge from available basin characteristics useful for most...
Influence of the Amlia fracture zone on the evolution of the Aleutian Terrace forearc basin, central Aleutian subduction zone
Holly F. Ryan, Amy E. Draut, Katie M. Keranen, David W. Scholl
2012, Geosphere (8) 1254-1273
During Pliocene to Quaternary time, the central Aleutian forearc basin evolved in response to a combination of tectonic and climatic factors. Initially, along-trench transport of sediment and accretion of a frontal prism created the accommodation space to allow forearc basin deposition. Transport of sufficient sediment to overtop the bathymetrically high...
Externally triggered renewed bubble nucleation in basaltic magma: the 12 October 2008 eruption at Halema‘uma‘u Overlook vent, Kīlauea, Hawai‘i, USA
Rebecca J. Carey, Michael Manga, Wim Degruyter, Donald Swanson, Bruce F. Houghton, Tim R. Orr, Matthew R. Patrick
2012, Journal of Geophysical Research B: Solid Earth (117)
From October 2008 until present, dozens of small impulsive explosive eruptions occurred from the Overlook vent on the southeast side of Halema‘uma‘u Crater, at Kīlauea volcano, USA. These eruptions were triggered by rockfalls from the walls of the volcanic vent and conduit onto the top of the lava column. Here...
Precision of channel catfish catch estimates using hoop nets in larger Oklahoma reservoirs
David R. Stewart, James M. Long
2012, North American Journal of Fisheries Management (32) 1108-1112
Hoop nets are rapidly becoming the preferred gear type used to sample channel catfish Ictalurus punctatus, and many managers have reported that hoop nets effectively sample channel catfish in small impoundments (<200 ha). However, the utility and precision of this approach in larger impoundments have not been tested. We sought...
Holocene diatom flora and climate history of Medicine Lake, Northern California, USA
Scott W. Starratt
2012, Nova Hedwigia, Beiheft (141) 485-504
A 226-cm-long sediment core spanning the past ~ 11,400 years was recovered from Medicine Lake, on the Modoc Plateau in northeastern California. Diatom assemblages provide a record of lake level that is driven by local and regional climate changes and changes in basin morphology due to the activity of Medicine...
Developing accurate survey methods for estimating population sizes and trends of the critically endangered Nihoa Millerbird and Nihoa Finch.
P. Marcos Gorresen, Richard J. Camp, Kevin W. Brinck, Chris Farmer
2012, Technical Report HCSU-034
This report describes the results of a comparative study of bird survey methods undertaken for the purpose of improving assessments of the conservation status for the two endemic passerines on the Island of Nihoa—Nihoa Millerbird (Sylviidae: Acrocephalus familiaris kingi) and Nihoa Finch (Fringilidae: Telespiza ultima; also referred herein as millerbird...
Phylogeographic implications for release of critically endangered manatee calves rescued in Northeast Brazil
Fabia O. Luna, Robert K. Bonde, Fernanda L.N. Attademo, Jonathan W. Saunders, Gaia Meigs-Friend, Jose Zanon O. Passavante, Margaret E. Hunter
2012, Aquatic Conservation: Marine and Freshwater Ecosystems (22) 665-672
1. The Antillean manatee (Trichechus manatus manatus), a subspecies of the West Indian manatee, is a large-bodied marine mammal found in fresh, brackish, and marine habitats throughout the Caribbean Islands and Central and South America. Antillean manatees in Brazil are classified as critically endangered, with a census size of approximately...
Predicting biological condition in southern California streams
Larry R. Brown, Jason T. May, Andrew C. Rehn, Peter R. Ode, Ian R. Waite, Jonathan G. Kennen
2012, Landscape and Urban Planning (108) 17-27
As understanding of the complex relations among environmental stressors and biological responses improves, a logical next step is predictive modeling of biological condition at unsampled sites. We developed a boosted regression tree (BRT) model of biological condition, as measured by a benthic macroinvertebrate index of biotic integrity (BIBI), for streams...
Occurrence and potential sources of pyrethroid insecticides in stream sediments from seven U.S. metropolitan areas
Kathryn Kuivila, Michelle Hladik, Christopher G. Ingersoll, Nile E. Kemble, Patrick W. Moran, Daniel L. Calhoun, Lisa H. Nowell, Robert J. Gilliom
2012, Environmental Science & Technology (46) 4297-4303
A nationally consistent approach was used to assess the occurrence and potential sources of pyrethroid insecticides in stream bed sediments from seven metropolitan areas across the United States. One or more pyrethroids were detected in almost half of the samples, with bifenthrin detected the most frequently (41%) and in each...
The hydrology of a drained topographical depression within an agricutlural field in north-central Iowa
Jason L. Roth, Paul D. Capel
2012, Transactions of the American Society of Agricultural and Biological Engineers (55) 1801-1814
North-central Iowa is an agriculturally intensive area comprising the southeastern portion of the Prairie Pothole Region, a landscape containing a high density of enclosed topographical depressions. Artificial drainage practices have been implemented throughout the area to facilitate agricultural production. Vertical surface drains are utilized to drain the topographical depressions that...
Recent advances in applying decision science to managing national forests
Bruce G. Marcot, Matthew P. Thompson, Michael C. Runge, Frank R. Thompson, Steven McNulty, David Cleaves, Monica Tomosy, Larry A. Fisher, Bliss Andrew
2012, Forest Ecology and Management (285) 123-132
Management of federal public forests to meet sustainability goals and multiple use regulations is an immense challenge. To succeed, we suggest use of formal decision science procedures and tools in the context of structured decision making (SDM). SDM entails four stages: problem structuring (framing the problem and defining objectives and...
Dissolved organic matter reduces algal accumulation of methylmercury
Allison C. Luengen, Nicholas S. Fisher, Brian A. Bergamaschi
2012, Environmental Toxicology and Chemistry (31) 1712-1719
Dissolved organic matter (DOM) significantly decreased accumulation of methylmercury (MeHg) by the diatom Cyclotella meneghiniana in laboratory experiments. Live diatom cells accumulated two to four times more MeHg than dead cells, indicating that accumulation may be partially an energy-requiring process. Methylmercury enrichment in diatoms relative to ambient water was measured...
The relationship between total cholinesterase activity and mortality in four butterfly species
Timothy A. Bargar
2012, Environmental Toxicology and Chemistry (31) 2124-2129
The relationship between total cholinesterase activity (TChE) and mortality in four butterfly species (great southern white [Ascia monuste], common buckeye [Junonia coenia], painted lady [Vanessa cardui], and julia butterflies [Dryas julia]) was investigated. Acute contact toxicity studies were conducted to evaluate the response (median lethal dose [LD50] and TChE) of...
Catalog of earthquake hypocenters at Alaskan volcanoes: January 1 through December 31, 2011
James P. Dixon, Scott D. Stihler, John A. Power, Cheryl K. Searcy
2012, Data Series 730
Between January 1 and December 31, 2011, the Alaska Volcano Observatory (AVO) located 4,364 earthquakes, of which 3,651 occurred within 20 kilometers of the 33 volcanoes with seismograph subnetworks. There was no significant seismic activity above background levels in 2011 at these instrumented volcanic centers. This catalog includes locations, magnitudes,...
United States Geological Survey fire science: Fire danger monitoring and forecasting
Jeff C. Eidenshink, Stephen M. Howard
2012, Fact Sheet 2012-3121
Each day, the U.S. Geological Survey produces 7-day forecasts for all Federal lands of the distributions of number of ignitions, number of fires above a given size, and conditional probabilities of fires growing larger than a specified size. The large fire probability map is an estimate of the likelihood that...
Pathology in euthermic bats with white nose syndrome suggests a natural manifestation of immune reconstitution inflammatory syndrome
Carol U. Meteyer, Daniel Barber, Judith N. Mandl
2012, Virulence (3) 583-588
White nose syndrome, caused by Geomyces destructans, has killed more than 5 million cave hibernating bats in eastern North America. During hibernation, the lack of inflammatory cell recruitment at the site of fungal infection and erosion is consistent with a temperature-induced inhibition of immune cell trafficking. This immune suppression allows...
A basin-scale approach for assessing water resources in a semiarid environment: San Diego region, California and Mexico
L. E. Flint, A. L. Flint, Bernard J. Stolp, W.R. Danskin
2012, Hydrology and Earth System Sciences (16) 3817-3833
Many basins throughout the world have sparse hydrologic and geologic data, but have increasing demands for water and a commensurate need for integrated understanding of surface and groundwater resources. This paper demonstrates a methodology for using a distributed parameter water-balance model, gaged surface-water flow, and a reconnaissance-level groundwater flow model...
Landslides in Colorado, USA--Impacts and loss estimation for 2010
Lynn M. Highland
2012, Open-File Report 2012-1204
The focus of this study is to investigate landslides and consequent losses which affected Colorado in the year 2010. By obtaining landslide reports from a variety of sources, this report will demonstrate the feasibility of creating a profile of landslides and their effects on communities. A short overview of the...
Watershed regressions for pesticides (warp) models for predicting atrazine concentrations in Corn Belt streams
Wesley W. Stone, Robert J. Gilliom
2012, Journal of the American Water Resources Association (48) 970-986
Watershed Regressions for Pesticides (WARP) models, previously developed for atrazine at the national scale, are improved for application to the United States (U.S.) Corn Belt region by developing region-specific models that include watershed characteristics that are influential in predicting atrazine concentration statistics within the Corn Belt. WARP models for the...
Compartment-based hydrodynamics and water quality modeling of a northern Everglades wetland, Florida, USA
Hongqing Wang, Ehab A. Meselhe, Michael G. Waldon, Matthew C. Harwell, Chunfang Chen
2012, Ecological Modelling (247) 273-285
The last remaining large remnant of softwater wetlands in the US Florida Everglades lies within the Arthur R. Marshall Loxahatchee National Wildlife Refuge. However, Refuge water quality today is impacted by pumped stormwater inflows to the eutrophic and mineral-enriched 100-km canal, which circumscribes the wetland. Optimal management is a challenge...
Investigation of land subsidence in the Houston-Galveston region of Texas by using the Global Positioning System and interferometric synthetic aperture radar, 1993-2000
Gerald W. Bawden, Michaela R. Johnson, Mark C. Kasmarek, Justin T. Brandt, Clifton S. Middleton
2012, Scientific Investigations Report 2012-5211
Since the early 1900s, groundwater has been the primary source of municipal, industrial, and agricultural water supplies for the Houston-Galveston region, Texas. The region's combination of hydrogeology and nearly century-long use of groundwater has resulted in one of the largest areas of subsidence in the United States; by 1979, as...
Prevalence of a potentially lethal parasite of wading birds in natural and agricultural wetlands in south Louisiana
Margaret C. Luent, Melissa Collins, Clinton Jeske, Paul Leberg
2012, Southeastern Naturalist (11) 415-422
Gambusia affinis (Western Mosquitofish) were sampled from 18 sites representing marsh, forested wetlands, and agricultural wetlands in south Louisiana to determine distribution and infection parameters of Eustrongylides ignotus, a potentially lethal nematode parasite of wading birds, (n = 400 per site). Overall, prevalence of infection was 0.3%, with significantly higher...
Hydrozincite seasonal precipitation at Naracauli (Sardinia – Italy): Hydrochemical factors and morphological features of the biomineralization process
D. Medas, R. Cidu, P. Lattanzi, F. Podda, Richard B. Wanty, G. De Giudici
2012, Applied Geochemistry (27) 1814-1820
Hydrozincite [Zn5(CO3)2(OH)6] precipitation from Naracauli waters (SW Sardinia) is, among other things, promoted by a microbial community made up of a filamentous cyanobacterium (Scytonema sp.) and a microalgae (Chlorella sp.). Hydrozincite bioprecipitation is responsible for the natural removal of harmful metals, especially Zn, from the stream waters. Thus, hydrozincite could be used...
