University of Georgia

About: University of Georgia is a education organization based out in Athens, Georgia, United States. It is known for research contribution in the topics: Population & Gene. The organization has 41934 authors who have published 93622 publications receiving 3713212 citations. The organization is also known as: UGA & Franklin College.

Climate change, hurricanes and tropical storms, and rising sea level in coastal wetlands

Abstract: Global climate change is expected to affect temperature and precipitation patterns, oceanic and atmospheric circulation, rate of rising sea level, and the frequency, intensity, timing, and distribution of hurricanes and tropical storms. The magnitude of these projected physical changes and their subsequent impacts on coastal wetlands will vary regionally. Coastal wetlands in the southeastern United States have naturally evolved under a regime of rising sea level and specific patterns of hurricane frequency, intensity, and timing. A review of known ecological effects of tropical storms and hurricanes indicates that storm timing, frequency, and intensity can alter coastal wetland hydrology, geomorphology, biotic structure, energetics, and nutrient cycling. Research conducted to examine the impacts of Hurricane Hugo on colonial waterbirds highlights the importance of long-term studies for identifying complex interactions that may otherwise be dismissed as stochastic processes. Rising sea level and even modest changes in the frequency, intensity, timing, and distribution of tropical storms and hurricanes are expected to have substantial impacts on coastal wetland patterns and processes. Persistence of coastal wetlands will be determined by the interactions of climate and anthropogenic effects, especially how humans respond to rising sea level and how further human encroachment on coastal wetlands affects resource exploitation, pollution, and water use. Long-term changes in the frequency, intensity, timing, and distribution of hurricanes and tropical storms will likely affect biotic functions (e.g., community structure, natural selection, extinction rates, and biodiversity) as well as underlying processes such as nutrient cycling and primary and secondary productivity. Reliable predictions of global-change impacts on coastal wetlands will require better understanding of the linkages among terrestrial, aquatic, wetland, atmospheric, oceanic, and human components. Developing this comprehensive understanding of the ecological ramifications of global change will necessitate close coordination among scientists from multiple disciplines and a balanced mixture of appropriate scientific approaches. For example, insights may be gained through the careful design and implementation of broad-scale comparative studies that incorporate salient patterns and processes, including treatment of anthropogenic influences. Well-designed, broad-scale comparative studies could serve as the scientific framework for developing relevant and focused long-term ecological research, monitoring programs, experiments, and modeling studies. Two conceptual models of broad-scale comparative research for assessing ecological responses to climate change are presented: utilizing space-for-time substitution coupled with long-term studies to assess impacts of rising sea level and disturbance on coastal wetlands, and utilizing the moisture-continuum model for assessing the effects of global change and associated shifts in moisture regimes on wetland ecosystems. Increased understanding of climate change will require concerted scientific efforts aimed at facilitating interdisciplinary research, enhancing data and information management, and developing new funding strategies.

The role of mindfulness in romantic relationship satisfaction and responses to relationship stress.

Abstract: Two studies examined the role of mindfulness in romantic relationship satisfaction and in responses to relationship stress. Using a longitudinal design, Study 1 found that higher trait mindfulness predicted higher relationship satisfaction and greater capacities to respond constructively to relationship stress. Study 2 replicated and extended these findings. Mindfulness was again shown to relate to relationship satisfaction; then, using a conflict discussion paradigm, trait mindfulness was found to predict lower emotional stress responses and positive pre- and postconflict change in perception of the relationship. State mindfulness was related to better communication quality during the discussion. Both studies indicated that mindfulness may play an influential role in romantic relationship well-being. Discussion highlights future research directions for this new area of inquiry.

Discovery and spectroscopy of the young Jovian planet 51 Eri b with the Gemini Planet Imager

Abstract: Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric compositions and luminosities, which are influenced by their formation mechanisms. Using the Gemini Planet Imager, we discovered a planet orbiting the ~20-million-year-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water-vapor absorption. Modeling of the spectra and photometry yields a luminosity (normalized by the luminosity of the Sun) of 1.6 to 4.0 × 10(-6) and an effective temperature of 600 to 750 kelvin. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold-start" core-accretion process that may have formed Jupiter.

What is hydrologic connectivity and why is it ecologically important

Abstract: Hydrologic connectivity (sensu Pringle, 2001) is used here in an ecological context to refer to water-mediated transfer of matter, energy and/or organisms within or between elements of the hydrologic cycle. Hydrologic connectivity is essential to the ecological integrity of the landscape, and reduction or enhancement of this property by humans can have major negative environmental effects. Some of these effects are immediate, localized and, therefore, obvious. For example, with respect to migratory fish, a given dam may act to reduce hydrologic connectivity (by preventing or impeding migration up or downstream), whereas interbasin river transfers enhance this property by allowing the dispersal of fish into river basins outside of their range. Less obvious, are alterations in hydrologic connectivity that exhibit a time lag and manifest themselves at geographic locations far from the source of disturbance. An example concerns the cumulative effect of dams on transport of the inorganic dissolved solute silica. Dams and associated impoundments can reduce the transport of this compound, which becomes deposited in the bottoms of reservoirs (Humborg et al., 2000). The cumulative effects of many dams along a river can potentially result in a reduction in the amount of silica delivered to coastal waters, with consequent negative effects on coastal food web structure that contribute to eutrophication (Justic et al., 1995; Turner et al., 1998). Management and policy decisions regarding land-use activities and hydropower development are often made in the absence of adequate information on hydrologic connectivity in the landscape. Our current knowledge of how this property maintains the ecological integrity of ‘natural’ ecosystems is poor due to: (1) the inherent complexity of water movement within and between the atmosphere and surface–subsurface systems; and (2) the extent and magnitude of human alterations, which often occur before we understand how hydrologic connectivity affects ecological patterns in the landscape (Pringle and Triska, 2000). Hydrologic connectivity is being altered at a rate unprecedented in geologic history, contributing to dramatic losses in global aquatic biodiversity and associated ecosystem integrity (e.g. Dudgeon, 2000; Pringle et al., 2000; Rosenberg et al., 2000). Humans have already appropriated one-half of the accessible global freshwater runoff and this could climb to 70% by 2025 (Postel et al., 1996).