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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 9967

Estimated water withdrawals and use in Puerto Rico, 2015

Water withdrawals and use in Puerto Rico for 2015 were estimated at 2,372 million gallons per day (Mgal/d), which was 21 percent less than withdrawals and use for 2010. The 2015 total water withdrawal and use estimates were the lowest since 1990 and coincided with a substantial decline of 25 percent in saline-water withdrawals for thermoelectric-power cooling processes from 2010 to 2015. Freshwate
Authors
Wanda L. Molina-Rivera, Michelle M. Irizarry-Ortiz

Forest thinning in the seaward fringe speeds up surface elevation increment and carbon accumulation in managed mangrove forests

Mangroves are significant carbon (C) sinks and ecological engineers as they accumulate sediments and increase soil surface elevation. Thus, the forest management practice of thinning may not only alter forest structure, but also facilitate new biogeomorphological processes that affect soil development. Thinning may create additional opportunity for understorey species, such as the light-demanding 
Authors
Luzhen Chen, Qiulian Lin, Ken Krauss, Yun Zhang, Nicole Cormier, Qiong Yang

Increasing hydroperiod in a karst-depression wetland based on 165 years of simulated daily water levels

The hydrology of seasonally inundated depression wetlands can be highly sensitive to climatic fluctuations. Hydroperiod—the number of days per year that a wetland is inundated—is often of primary ecological importance in these systems and can vary interannually depending on climate conditions. In this study we re-examined an existing hydrologic model to simulate daily water levels in Sinking Pond,
Authors
Jennifer M. Cartwright, William J. Wolfe

Approaches for assessing long-term annual yields of highway and urban runoff in selected areas of California with the Stochastic Empirical Loading and Dilution Model (SELDM)

The California Department of Transportation, commonly known as CalTrans, and other municipal separate storm sewer system permittees in California as well as other State departments of transportation nationwide need information about potential loads and yields (loads per unit area) of constituents of concern in stormwater runoff and discharges from stormwater best management practices (BMPs). Altho
Authors
Gregory E. Granato, Paul J. Friesz

Hydrogeologic framework and groundwater characterization in selected alluvial basins in the upper Rio Grande basin, Colorado, New Mexico, and Texas, United States, and Chihuahua, Mexico, 1980 to 2015

Increasing demand for the limited water resources of the United States continues to put pressure on resource management agencies to balance the competing needs of ecosystem health with municipal, agricultural, and other uses. To meet these needs, the U.S. Geological Survey conducted a multiyear study to evaluate water resources in the upper Rio Grande Basin in the southwestern United States. The u
Authors
Natalie A. Houston, Jonathan V. Thomas, Linzy K. Foster, Diana E. Pedraza, Toby L. Welborn

Metal accumulation varies with life history, size, and development of larval amphibians

Amphibian larvae are commonly used as indicators of aquatic ecosystem health because they are susceptible to contaminants. However, there is limited information on how species characteristics and trophic position influence contaminant loads in larval amphibians. Importantly, there remains a need to understand whether grazers (frogs and toads [anurans]) and predators (salamanders) provide comparabl
Authors
Kelly L. Smalling, Emily Bea Oja, Danielle M. Cleveland, Jon D Davenport, Collin Eagles-Smith, Evan H. Campbell Grant, Patrick M. Kleeman, Brian J. Halstead, Kenzi M Stemp, Brian J. Tornabene, Zachary J Bunnell, Blake R. Hossack

Grassland live fractional cover map creation and Geographic Information System (GIS) analysis for rangeland management supporting Kenya Northern Rangelands Trust Conservancies

The handbooks and synchronized MP4 recordings provide hands-on instruction for creating and analyzing vegetation live fractional cover (LFC) maps. The methods and protocols used in the instruction materials follow those developed and recorded in Rangoonwala and Ramsey (2019). The LFC mapping and geographic information system (GIS) analyses highlight the consortium of rangeland conservancies coveri
Authors
Amina Rangoonwala, Elijah Ramsey

Airborne geophysical surveys of the lower Mississippi Valley demonstrate system-scale mapping of subsurface architecture

The Mississippi Alluvial Plain hosts one of the most prolific shallow aquifer systems in the United States but is experiencing chronic groundwater decline. The Reelfoot rift and New Madrid seismic zone underlie the region and represent an important and poorly understood seismic hazard. Despite its societal and economic importance, the shallow subsurface architecture has not been mapped with the sp
Authors
Burke J. Minsley, James R. Rigby, Stephanie R. James, Bethany L. Burton, Katherine J. Knierim, Michael Pace, Paul A. Bedrosian, Wade Kress

Climate and the latitudinal limits of subtropical reef development

Climate plays a central role in coral-reef development, especially in marginal environments. The high-latitude reefs of southeast Florida are currently non-accreting, relict systems with low coral cover. This region also did not support the extensive Late Pleistocene reef development observed in many other locations around the world; however, there is evidence of significant reef building in south
Authors
Lauren Toth, William F. Precht, Alexander B. Modys, Anastasios Stathakopoulos, Martha L. Robbart, J. Harold Hudson, Anton E. Olenik, Bernhard M Riegl, Eugene A. Shinn, Richard B. Aronson

Physiological differences in bleaching response of the coral Porites astreoides along the Florida Keys reef tract during high-temperature stress

The Florida Keys reef tract (FKRT) has a unique geological history wherein Holocene sea-level rise and bathymetry interacted, resulting in a reef-building system with notable spatial differences in reef development. Overprinted on this geologic history, recent global and local stressors have led to degraded reefs dominated by fleshy algae, soft corals, and sponges. Here, we assessed how coral phys
Authors
Elizabeth A. Lenz, Lucy Bartlett, Anastasios Stathakopoulos, Ilsa B. Kuffner

Monitoring abundance of aggregated animals (Florida manatees) using an unmanned aerial system (UAS)

Imperfect detection is an important problem when counting wildlife, but new technologies such as unmanned aerial systems (UAS) can help overcome this obstacle. We used data collected by a UAS and a Bayesian closed capture-mark-recapture model to estimate abundance and distribution while accounting for imperfect detection of aggregated Florida manatees (Trichechus manatus latirostris) at thermal re
Authors
Holly H Edwards, Jeffrey A. Hostetler, Bradley M Stith, Julien Martin

Assessing habitat change and migration of barrier islands

Barrier islands are dynamic environments that experience gradual change from waves, tides, and currents, and rapid change from extreme storms. These islands are expected to change drastically over the coming century due to accelerated sea-level rise and changes in frequency and intensity of storm events. The dynamic nature of barrier islands coupled with the importance of these environments make i
Authors
Nicholas Enwright, Lei Wang, P. Soupy Dalyander, Hongqing Wang, Michael Osland, Rangley C. Mickey, Robert L. Jenkins, Elizabeth Godsey