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Taking a systems approach to ecological systems Taking a systems approach to ecological systems

Increasingly, there is interest in a systems-level understanding of ecological problems, which requires the evaluation of more complex, causal hypotheses. In this issue of the Journal of Vegetation Science, Soliveres et al. use structural equation modeling to test a causal network hypothesis about how tree canopies affect understorey communities. Historical analysis suggests structural...
Authors
James B. Grace

Hyla chrysoscelis (Cope’s gray treefrog) x Hyla cinerea (green treefrog): putative natural hybrid Hyla chrysoscelis (Cope’s gray treefrog) x Hyla cinerea (green treefrog): putative natural hybrid

Naturally–occurring hybrid treefrogs have been occasionally found in the eastern United States. However, these hybrids are almost always between members of the same species group. On 10 Jun 2014, at 2145 h, we located an individual making an unusual advertisement call along Bayou Manual Road in Sherburne Wildlife Management Area in the Atchafalaya Basin of south-central Louisiana, USA...
Authors
Brad M. Glorioso, J. Hardin Waddle, Jill A. Jenkins, Heather M. Olivier, Rebekah R. Layton

Statistical models for the analysis and design of digital polymerase chain (dPCR) experiments Statistical models for the analysis and design of digital polymerase chain (dPCR) experiments

Statistical methods for the analysis and design of experiments using digital PCR (dPCR) have received only limited attention and have been misused in many instances. To address this issue and to provide a more general approach to the analysis of dPCR data, we describe a class of statistical models for the analysis and design of experiments that require quantification of nucleic acids...
Authors
Robert Dorazio, Margaret Hunter

Structural classification of marshes with Polarimetric SAR highlighting the temporal mapping of marshes exposed to oil Structural classification of marshes with Polarimetric SAR highlighting the temporal mapping of marshes exposed to oil

Empirical relationships between field-derived Leaf Area Index (LAI) and Leaf Angle Distribution (LAD) and polarimetric synthetic aperture radar (PolSAR) based biophysical indicators were created and applied to map S. alterniflora marsh canopy structure. PolSAR and field data were collected near concurrently in the summers of 2010, 2011, and 2012 in coastal marshes, and PolSAR data alone...
Authors
Elijah W. Ramsey, Amina Rangoonwala, Cathleen E. Jones

Community for Data Integration 2014 annual report Community for Data Integration 2014 annual report

The U.S. Geological Survey (USGS) researches Earth science to help address complex issues affecting society and the environment. In 2006, the USGS held the first Scientific Information Management Workshop to bring together staff from across the organization to discuss the data and information management issues affecting the integration and delivery of Earth science research and...
Authors
Madison L. Langseth, Michelle Y. Chang, Jennifer Carlino, Daniella D. Birch, Joshua Bradley, R. Sky Bristol, Craig Conzelmann, Robert H. Diehl, Paul S. Earle, Laura E. Ellison, Anthony L. Everette, Pamela L. Fuller, Janice M. Gordon, David L. Govoni, Michelle R. Guy, Heather S. Henkel, Vivian B. Hutchison, Tim Kern, Frances L. Lightsom, Joseph W. Long, Ryan Longhenry, Todd M. Preston, Stan W. Smith, Roland J. Viger, Katherine E. Wesenberg, Eric C. Wood

Generic reclassification and species boundaries in the rediscovered freshwater mussel ‘Quadrula’ mitchelli (Simpson in Dall, 1896) Generic reclassification and species boundaries in the rediscovered freshwater mussel ‘Quadrula’ mitchelli (Simpson in Dall, 1896)

The Central Texas endemic freshwater mussel, Quadrula mitchelli (Simpson in Dall, 1896), had been presumed extinct until relict populations were recently rediscovered. To help guide ongoing and future conservation efforts focused on Q. mitchelli we set out to resolve several uncertainties regarding its evolutionary history, specifically its unknown generic position and untested species...
Authors
John M. Pfeiffer, Nathan A. Johnson, Charles R. Randklev, Robert G. Howells, James D. Williams

Malaclemys terrapin rhizophorarum (mangrove diamond-backed terrapin) Malaclemys terrapin rhizophorarum (mangrove diamond-backed terrapin)

MALACLEMYS TERRAPIN RHIZOPHORARUM (Mangrove Diamond-backed Terrapin). DIET. Malaclemys terrapin rhizophorarum, one of seven subspecies of M. terrapin, inhabits subtropical mangrove habitats in South Florida, USA. In temperate climates M. terrapin is largely carnivorous, feeding primarily on gastropods, bivalves, and decapod crustaceans (Tucker et. al. 1995. Herpetologica 51:167–181...
Authors
Mathew J. Denton, Kristen M. Hart, Anton Oelinik, Roger Wood, John N. Baldwin

Life stage influences the resistance and resilience of black mangrove forests to winter climate extremes Life stage influences the resistance and resilience of black mangrove forests to winter climate extremes

In subtropical coastal wetlands on multiple continents, climate change-induced reductions in the frequency and intensity of freezing temperatures are expected to lead to the expansion of woody plants (i.e., mangrove forests) at the expense of tidal grasslands (i.e., salt marshes). Since some ecosystem goods and services would be affected by mangrove range expansion, there is a need to...
Authors
Michael J. Osland, Richard H. Day, Andrew S. From, Megan L. McCoy, Jennie L. McLeod, Jeffrey Kelleway

Application of a coupled vegetation competition and groundwater simulation model to study effects of sea level rise and storm surges on coastal vegetation Application of a coupled vegetation competition and groundwater simulation model to study effects of sea level rise and storm surges on coastal vegetation

Global climate change poses challenges to areas such as low-lying coastal zones, where sea level rise (SLR) and storm-surge overwash events can have long-term effects on vegetation and on soil and groundwater salinities, posing risks of habitat loss critical to native species. An early warning system is urgently needed to predict and prepare for the consequences of these climate-related...
Authors
Su Yean Teh, Michael Turtora, Donald L. DeAngelis, Jiang Jiang, Leonard G. Pearlstine, Thomas J. Smith, Hock Lye Koh

Landscape structure affects specialists but not generalists in naturally fragmented grasslands Landscape structure affects specialists but not generalists in naturally fragmented grasslands

Understanding how biotic communities respond to landscape spatial structure is critically important for conservation management as natural landscapes become increasingly fragmented. However, empirical studies of the effects of spatial structure on plant species richness have found inconsistent results, suggesting that more comprehensive approaches are needed. In this study, we asked how...
Authors
Jesse Miller, Ellen Ingman Damschen, Susan P. Harrison, James B. Grace

Field and laboratory guide to freshwater cyanobacteria harmful algal blooms for Native American and Alaska Native communities Field and laboratory guide to freshwater cyanobacteria harmful algal blooms for Native American and Alaska Native communities

Cyanobacteria can produce toxins and form harmful algal blooms. The Native American and Alaska Native communities that are dependent on subsistence fishing have an increased risk of exposure to these cyanotoxins. It is important to recognize the presence of an algal bloom in a waterbody and to distinguish a potentially toxic harmful algal bloom from a non-toxic bloom. This guide provides...
Authors
Barry H. Rosen, Ann E. St. Amand

Bistability of mangrove forests and competition with freshwater plants Bistability of mangrove forests and competition with freshwater plants

Halophytic communities such as mangrove forests and buttonwood hammocks tend to border freshwater plant communities as sharp ecotones. Most studies attribute this purely to underlying physical templates, such as groundwater salinity gradients caused by tidal flux and topography. However, a few recent studies hypothesize that self-reinforcing feedback between vegetation and vadose zone...
Authors
Jiang Jiang, Douglas O Fuller, Su Yean Teh, Lu Zhai, Hock Lye Koh, Donald L. DeAngelis, L.D.S.L. Sternberg
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