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Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16784

Temperature sensitivity of organic-matter decay in tidal marshes

Approximately half of marine carbon sequestration takes place in coastal wetlands, including tidal marshes, where organic matter contributes to soil elevation and ecosystem persistence in the face of sea-level rise. The long-term viability of marshes and their carbon pools depends, in part, on how the balance between productivity and decay responds to climate change. Here, we report the sensitivit
Authors
Matthew L. Kirwan, Glenn R. Guntenspergen, J.A. Langley

A simple headspace equilibration method for measuring dissolved methane

Dissolved methane concentrations in the ocean are close to equilibrium with the atmosphere. Because methane is only sparingly soluble in seawater, measuring it without contamination is challenging for samples collected and processed in the presence of air. Several methods for analyzing dissolved methane are described in the literature, yet none has conducted a thorough assessment of the method yie
Authors
C Magen, L. L. Lapham, John W. Pohlman, Kristin N. Marshall, S. Bosman, Michael Casso, J. P. Chanton

Observations from borehole dilution logging experiments in fractured crystalline rock under variable hydraulic conditions

Identifying hydraulically active fractures in low permeability, crystalline-bedrock aquifers requires a variety of geophysical and hydrogeophysical borehole tools and approaches. One such approach is Single Borehole Dilution Tests (SBDT), which in some low flow cases have been shown to provide greater resolution of borehole flow than other logging procedures, such as vertical differential Heat Pul
Authors
Philip T. Harte, J. Alton Anderson, John H. Williams

Hydroclimatic regimes: a distributed water-balance framework for hydrologic assessment, classification, and management

Runoff-based indicators of terrestrial water availability are appropriate for humid regions, but have tended to limit our basic hydrologic understanding of drylands – the dry-subhumid, semiarid, and arid regions which presently cover nearly half of the global land surface. In response, we introduce an indicator framework that gives equal weight to humid and dryland regions, accounting fully for bo
Authors
Peter K. Weiskel, David M. Wolock, Phillip J. Zarriello, Richard M. Vogel, Sara B. Levin, Robert M. Lent

Sulfur and oxygen isotopic study of Paleozoic sediment-hosted Zn-Pb(-Ag-Au-Ba-F) deposits and associated hydrothermal alteration zones in the Nome Complex, Seward Peninsula, Alaska

Results of sulfur and oxygen isotope studies of sedimentary exhalative (SEDEX) Zn-Pb(-Ag-Au-Ba-F) deposits hosted in metamorphosed Paleozoic clastic and carbonate rocks of the Nome Complex, Seward Peninsula, Alaska, are consistent with data for similar deposits worldwide. Stable isotopic studies of the Nome Complex are challenging because the rocks have undergone Mesozoic blueschist- and greensch
Authors
W.C. Pat Shanks, John F. Slack, Alison B. Till, Roland Thurston, Pamela Gemery-Hill

Bathymetric Terrain Model of the Puerto Rico Trench and the Northeastern Caribbean Region for Marine Geological Investigations

Multibeam bathymetry data collected in the Puerto Rico Trench and Northeast Caribbean region are compiled into a seamless bathymetric terrain model for broad-scale geological investigations of the trench system. These data, collected during eight separate surveys between 2002 and 2013, covering almost 180,000 square kilometers are published here in large format map sheet and digital spatial data.

Authors
Brian D. Andrews, Uri S. ten Brink, William W. Danforth, Jason D. Chaytor, J Granja-Bruna, A Carbo-Gorosabel

Gymnophthalmus speciosus (golden spectacled tegu): predation by great egret

No abstract available.
Authors
Robert P. Reynolds, James F. Whatton, Christina A. Gebhard

Kaolin

The article reports on the market performance of kaolin in the U.S. in 2009 and presents an outlook for its 2010 performance. There was a decline in the domestic sales of kaolin from 6.74 measurement ton (Mt) to 5.2 Mt. Companies in the country engaged in kaolin production include Advanced Primary Minerals Corp., Applied Minerals Inc., and Daleco Resources Corp. The decline in world production of
Authors
Robert L. Virta

Management and monitoring of the endangered Shenandoah salamander under climate change: Workshop report 10-12 April 2012

Here we report on a structured decision making (SDM) process to identify management strategies to ensure persistence of the federally endangered Shenandoah salamander (Plethodon shenandoah), given that it may be at increased extinction risk under projected climate change. The focus of this report is the second of two SDM workshops; in the first workshop, participants developed a prototype of the d
Authors
Evan H. Campbell Grant, John E. B. Wofford, D. R. Smith, J. Dennis, C. Hawkins-Hoffman, J. Schaberl, M. Foley, M. Bogle

Modeling structured population dynamics using data from unmarked individuals

The study of population dynamics requires unbiased, precise estimates of abundance and vital rates that account for the demographic structure inherent in all wildlife and plant populations. Traditionally, these estimates have only been available through approaches that rely on intensive mark–recapture data. We extended recently developed N-mixture models to demonstrate how demographic parameters a
Authors
Evan H. Campbell Grant, Elise Zipkin, James T. Thorson, Kevin See, Heather J. Lynch, Yoichiro Kanno, Richard Chandler, Benjamin H. Letcher, J. Andrew Royle

Stream water temperature limits occupancy of salamanders in mid-Atlantic protected areas

Stream ecosystems are particularly sensitive to urbanization, and tolerance of water-quality parameters is likely important to population persistence of stream salamanders. Forecasted climate and landscape changes may lead to significant changes in stream flow, chemical composition, and temperatures in coming decades. Protected areas where landscape alterations are minimized will therefore become
Authors
Evan H. Campbell Grant, Amber N. M. Wiewel, Karen C. Rice

Chromic and iron oxides as fecal markers to identify individual whooping cranes

The whooping crane (Grus americana) is listed as endangered under the IUCN Red List, the United States Endangered Species Act, and the Canadian Species at Risk Act (BirdLife International 2012, CWS and USFWS 2007). A major focus of recovery efforts for this endangered species is reintroduction to establish new populations (CWS and USFWS 2007). Captive populations are critical as a source of indivi
Authors
Megan E. Brown, Robert Doyle, Jane N. Chandler, Glenn H. Olsen, John B. French, David E Wildt, Sarah J. Converse, Carol L Keefer, Nucharin Songsasen