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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 9967

Contaminant subsidies to riparian food webs in Appalachian streams impacted by mountaintop removal coal mining

Selenium is highly elevated in Appalachian streams and stream organisms that receive alkaline mine drainage from mountaintop removal coal mining compared to unimpacted streams in the region. Adult aquatic insects can be important vectors of waterborne contaminants to riparian food webs, yet pathways of Se transport and exposure of riparian organisms are poorly characterized. We investigated Se con
Authors
Laura C. Naslund, Jacqueline R. Gerson, Alexander C. Brooks, David Walters, Emily S. Bernhardt

A within-season approach for detecting early crop stage of corn and soybean using high temporal and spatial resolution imagery

Crop emergence is a critical stage for crop development and crop growth modeling. Mapping crop emergence using remote sensing data is challenging. Previous remote sensing phenology algorithms showed that crop stages could be detected around the V3-V4 (3 to 4 established leaves) vegetative stage. Traditional approaches have a strong assumption regarding the temporal evolution of plant growth and no
Authors
Feng Gao, Martha Anderson, Craig S. T. Daughtry, Arnon Karnieli, W. Dean Hively, William P. Kustas

Water resources of Union Parish, Louisiana

Information concerning the availability, use, and quality of water in Union Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, about 4.88 million gallons per day (Mgal/d) of water were withdrawn in Union Parish: 4
Authors
Angela L. Robinson

Physical characteristics and simulated transport of pallid sturgeon and shovelnose sturgeon eggs

The imperiled pallid sturgeon (Scaphirhynchus albus) and closely related, but more common, shovelnose sturgeon (S. platorynchus) are believed to broadcast adhesive, demersal eggs in the current and over coarse substrate in turbid rivers of the North American midcontinent. It has been hypothesized that eggs settle immediately following fertilization, but field conditions preclude direct observation.
Authors
Kimberly Chojnacki, Susannah O. Erwin, Amy E. George, James Candrl, Robert B. Jacobson, Aaron J. Delonay

An overview of agent-based models in plant biology and ecology

Agent-based modeling (ABM) has become an established methodology in many areas of biology, ranging from the cellular to the ecological population and community levels. In plant science, two different scales have predominated in their use of ABM. One is the scale of populations and communities, through the modeling of collections of agents representing individual plants, interacting with each other
Authors
Bo Zhang, Donald L. DeAngelis

A 'weight of evidence' approach to evaluating structural equation models

It is possible that model selection has been the most researched and most discussed topic in the history of both statistics and structural equation modeling (SEM). The reason for this is because selecting one model for interpretive use from amongst many possible models is both essential and difficult. The published protocols and advice for model evaluation and selection in SEM studies are complex
Authors
James Grace

Landfill leachate contributes per-/poly-fluoroalkyl substances (PFAS) and pharmaceuticals to municipal wastewater

Widespread disposal of landfill leachate to municipal sewer infrastructure in the United States calls for an improved understanding of the relative organic-chemical contributions to the wastewater treatment plant (WWTP) waste stream and associated surface-water discharge to receptors in the environment. Landfill leachate, WWTP influent, and WWTP effluent samples were collected from three landfill-
Authors
Jason R. Masoner, Dana W. Kolpin, Isabelle M. Cozzarelli, Kelly L. Smalling, Stephanie Bolyard, Jennifer Field, Edward T. Furlong, James L. Gray, Duncan Lozinski, Debra Reinhart, Alix Rodowa, Paul M. Bradley

Structural equation modeling

This chapter introduces background and historical information on how structural equation modeling (SEM) came to be developed. Then, the main differences between SEM and earlier multivariate methods are explained. The chapter describes three main applications of SEM: path analysis, factor analysis, and hybrid models. Some computer programs are recommended for these applications. The step-by-step se
Authors
Matt Miller, Ivana Tasic, Torrey Lyons, Reid Ewing, James B. Grace

Louisiana Adaptive Management Status and Improvement Report: Vision and Recommendations

As part of the process to increase implementation of adaptive management for ecosystem-based coastal restoration within Louisiana, we aim for this report to be broadly applicable across planning processes as well as funding and implementing entities. It compiles technical knowledge and guidance summarized as key findings through the text which lead to eight priority recommendations to improve appl
Authors
Bill Boshart, Morgan Crutcher, Angelina Freeman, Edward Haywood, Syed M. Khalil, Summer Langlois, Darin L. Lee, David Lindquist, Tommy E. McGinnis, James Pahl, Carol Parsons-Richards, Erin Plitsch, Rick Raynie, Robert Routon, Leigh Anne Sharp, John Troutman, Chuck Villarrubia, Todd Folse, Alyson Graugnard, Anne Hawes, Russ Joffrion, Wes Leblanc, Brian Lezina, Jim Pahl, Jody White, Craig Conzelmann, Ann Hijuelos, Sarai Piazza, Kathryn A. Spear, Gregory D. Steyer, Nanciann Regalado, John M. Tirpak, Courtney Schupp, Melissa Carle, Jaclyn Daly, Nicolas Eckhardt, Christy Fellas, Erin M. Fougeres, Stephen Heverly, Stacey Horstman, Jason Kroll, Mel Landry, Barbara A. Schroeder, Eric Weissberger, Sara Wissman, Treda Grayson, Patricia Taylor, Danny Wiegand, Mark Defley, Paulina Kolic, Harris Bienn, Tim J. B. Carruthers, Alyssa Dausman, Alaina Grace, Scott Hemmerling, Andrea Jerabek, Eric White, Ryan Clark, Coleen McHugh, Leland C Moss, Cyndhia Ramatchandirane, Amy Wold

Antibiotic resistance in marine microbial communities proximal to a Florida sewage outfall system

Water samples were collected at several wastewater treatment plants in southeast Florida, and water and sediment samples were collected along and around one outfall pipe, as well as along several transects extending both north and south of the respective outfall outlet. Two sets of samples were collected to address potential seasonal differences, including 38 in the wet season (June 2018) and 42 i
Authors
Dale W. Griffin, Kenneth Banks, Kurtis Gregg, Sarah Shedler, Brian Walker

Uptake and toxicity of clothianidin to monarch butterflies from milkweed consumption

Recent concern for the adverse effects from neonicotinoid insecticides has centered on risk for insect pollinators in general and bees specifically. However, natural resource managers are also concerned about the risk of neonicotinoids to conservation efforts for the monarch butterfly (Danaus plexippus) and need additional data to help estimate risk for wild monarch butterflies exposed to those in
Authors
Timothy A. Bargar, Michelle L. Hladik, Jaret C. Daniels

Potential impacts of future urbanization and sea level rise on Florida’s natural resources

As urban development continues to encroach into natural systems, these ecosystems experience increasing degradation to their form and function. Losses in biodiversity and ecosystem function are further compounded by changing climatic conditions. The State of Florida is known for its biodiversity but has experienced declines in species populations and habitats because of urbanization and sea level
Authors
Stephanie Romanach, Allison Benscoter, Saira Haider