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Filter Total Items: 3367

Book review: Quasispecies as a unifying concept in population dynamics

The quasispecies concept had two independent origins. One source was the theoretical ideas of Manfred Eigen and Peter Schuster in the 1970s. Studying the self-organization and evolution of primitive RNA molecules, they defined quasispecies as a distribution of mutant viral genomes generated by the mutation-selection process. In particular, the quasispecies nucleotide distribution consists of a sin
Authors
Don DeAngelis

Declines in reproductive condition of male largemouth bass (Micropterus salmoides) following seasonal exposure to estrogenic endocrine-disrupting compounds

Reproductive abnormalities, that could lead to possible effects at the population level, have been observed in wild fish throughout the United States, with high prevalence in largemouth bass (LMB; Micropterus salmoides) and smallmouth bass (Micropterus dolomieu). Estrone (E1) and atrazine (ATR) are common environmental contaminants often associated with agricultural land use. 17alpha-ethinylestrad
Authors
Jessica Kristin Leet, Cathy A. Richter, Robert Gale, Donald E. Tillitt, Jill Jenkins

Disentangling direct and indirect effects of extreme events on coastal wetland communities

One of the primary ways in which climate change will impact coastal freshwater wetlands is through changes in the frequency, intensity, timing and distribution of extreme weather events. Disentangling the direct and indirect mechanisms of population- and community-level responses to extreme events is vital to predicting how species composition of coastal wetlands will change under future condition
Authors
Courtney L. Davis, Susan Walls, William Barichivich, Mary Brown, David A.W. Miller

Habitat utilization, demography, and behavioral observations of the squat lobster, Eumunida picta (Crustacea: Anomura: Eumunididae), on western North Atlantic deep-water coral habitats

Deep-sea coral habitats, comprising mostly Lophelia pertusa (Linnaeus 1758), are well developed on the upper and middle continental slope off the southeastern United States (SEUS). These habitats support a diverse and abundant invertebrate fauna, yet ecology and biology of most of these species are poorly known. Ten cruises conducted off the SEUS (Summer–Fall; Cape Lookout, NC–Cape Canaveral, FL)
Authors
Martha S. Nizinski, Jennifer McClain Counts, Steve W. Ross

Effects of shading on the rare plant species, Physostegia correllii (Lamiaceae) and Trillium texanum (Melanthiaceae)

Rare plant species that are constrained by shading may be threatened by a lack of natural disturbance that removes overhanging vegetation. The original distribution of the study species Physostegia correllii (Lundell) Shinners included freshwater floodplains of large rivers in the southcentral U.S. (Colorado, Rio Grande, and Mississippi rivers). A second species, Trillium texanum Buckley was found
Authors
Beth Middleton, Casey R. Williams, Chris Doffitt, Darren Johnson

Endangered Cape Sable seaside sparrow ecology: Actions towards recovery through landscape-scale ecosystem restoration

Understanding the ecology of endangered taxa and the factors affecting their population growth and decline is imperative for their recovery. In the southeastern USA, the Everglades wetland ecosystem supports a high diversity of species and communities, including many endemic and imperiled taxa, such as the federally endangered Cape Sable seaside sparrow Ammospiza maritima mirabilis (CSSS). The Eve
Authors
Allison Benscoter, Stephanie Romanach

Towards a unified drag coefficient formula for quantifying wave energy reduction by salt marshes

Coastal regions are susceptible to increasing flood risks amid climate change. Coastal wetlands play an important role in mitigating coastal hazards. Vegetation exerts a drag force to the flow and dampens storm surges and wind waves. The prediction of wave attenuation by vegetation typically relies on a pre-determined drag coefficient CD. Existing CD formulas are subject to vegetation biomechanica
Authors
Ling Zhu, Q. Chen, Yan Ding, Navid H. Jafari, Hongqing Wang, Bradley D. Johnson

Size distribution and reproductive phenology of the invasive Burmese python (Python molurus bivittatus) in the Greater Everglades Ecosystem, Florida, USA

The design of successful invasive species control programs is often hindered by the absence of basic demographic data on the targeted population. Establishment of invasive Burmese pythons (Python molurus bivittatus) in the Greater Everglades Ecosystem, Florida USA has led to local precipitous declines (> 90%) of mesomammal populations and is also a major threat to native populations of reptiles an
Authors
Andrea Faye Currylow, Bryan Falk, Amy A. Yackel Adams, Christina M. Romagosa, Jillian Josimovich, Michael R. Rochford, Michael Cherkiss, Melia Gail Nafus, Kristen Hart, Frank J. Mazzotti, Ray W. Snow, Robert Reed

Piñon and juniper tree removal increases available soil water, driving understory response in a sage-steppe ecosystem

Over the past century, piñon and juniper trees have encroached into sagebrush steppe lands of the interior United States, and managers have for many years removed trees to stimulate the favored understory. While consistent understory response to tree removal in these semiarid lands suggests that trees outcompete other plants for water, no studies have linked increased soil water to understory resp
Authors
James D. McIver, James Grace, Bruce A. Roundy

Response of soil respiration to changes in soil temperature and water table level in drained and restored peatlands of the southeastern United States

Extensive drainage of peatlands in the southeastern United States coastal plain for the purposes of agriculture and timber harvesting has led to large releases of soil carbon as carbon dioxide (CO2) due to enhanced peat decomposition. Growth in mechanisms that provide financial incentives for reducing emissions from land use and land-use change could increase funding for hydrological restoration t
Authors
Erin E. Swails, Marcelo Ardon, Ken Krauss, A.L. Peralta, Ryan E. Emmanuel, A.M. Helton, J.L. Morse, Laurel Gutenberg, Nicole Cormier, D. Shoch, Scott Settlemyer, Eric Soderholm, Brian P. Boutin, Chuck Peoples, Sara Ward

Trends in vegetation and height of the topographic surface in a tidal freshwater swamp experiencing rooting zone saltwater intrusion

A decrease in the ground surface height of coastal wetlands is of worldwide concern because of its relationship to peat loss, coastal carbon, and biodiversity in freshwater wetlands. We asked if it is possible to determine indicators of impending transitions of freshwater swamps to other coastal types by examining long-term changes in the environment and vegetation. In a tidal Taxodium distichum s
Authors
Beth Middleton, John L. David

Movements and habitat use of the Florida manatee (Trichechus manatus latirostris) in the northern Gulf of Mexico

No abstract available.
Authors
Daniel Slone, Susan M. Butler, James P. Reid, Cathy Beck, Robert Bonde