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Jaime A Collazo

We developed a spatially explicit model that simulated future southern pine beetle (Dendroctonus frontalis, SPB) dynamics and pine forest management for a real landscape over 60 years to inform regional forest management. The SPB has a considerable effect on forest dynamics in the Southeastern United States, especially in loblolly pine (Pinus taeda) stands that are managed for timber production. Regional outbreaks of SPB occur in bursts resulting in elimination of entire stands and major economic loss. These outbreaks are often interspersed with decades of inactivity, making long-term modeling of SPB dynamics challenging. Forest management techniques, including thinning, have proven effective and are often recommended...
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We determined their critical thermal maximum (CTMax) of four species of Eleutherodactylus frogs (E. wightmanae, E. brittoni, E. antillensis, E. coqui) to understand their response to warming temperatures. Data consist of capture history, body condition, and temperature at which the frog exhibited spasms and erratic behavior, which may impair predator avoidance. Our results underscored the potential vulnerability of Eleutherodactylus species exhibiting lower CTMax to the forecasted warming of tropical zones (e.g., E. wightmanae, E. brittoni).
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Amphibians are vulnerable to extinction owing, partly, to altered physiological processes induced by projected global warming and drying. Understanding the mechanisms behind their responses is essential to formulate adaptation strategies for their conservation. Puerto Rico harbors 15 endemic Eleutherodactylus frogs considered vulnerable to extinction due to poor vagility and sensitivity to environmental variability. Herein are reported the effects of four temperature treatments (15, 20, 25, and 30 degrees Centigrade) on metabolic rates associated with specific dynamic action (SDA) and standard metabolic rates (SMR) of four representative species of Eleutherodactylus employing a respirometer. All species in either...
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Amphibians in the US Caribbean, like the well-known coquí frog, are particularly vulnerable to human-caused climate change. Coquí frogs are represented by 17 species across Puerto Rico and US Virgin Islands and include several mountainous and coastal species that are threatened by extreme heat and drying, loss of coastal freshwater marshes through saltwater intrusion, or both. Over the past decade, the Southeast Climate Adaptation Science Center has invested in several scientific investigations to understand how global climate change is likely to affect the local climate of the US Caribbean and how sensitive different coquí species are to changes in local climate and habitat conditions in Puerto Rico. This project...
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This dataset represents the extent of urbanization (for the year indicated) predicted by the model SLEUTH, developed by Dr. Keith C. Clarke, at the University of California, Santa Barbara, Department of Geography and modified by David I. Donato of the United States Geological Survey (USGS) Eastern Geographic Science Center (EGSC). Further model modification and implementation was performed at the Biodiversity and Spatial Information Center at North Carolina State University. Purpose: Urban growth probability extents throughout the 21st century for the Southeast Regional Assessment Project, which encompasses the states of Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee...
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