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601.
Payal Shah Mindy L. Mallory Amy W. Ando Glenn R. Guntenspergen 《Conservation biology》2017,31(2):278-289
Climate‐change induced uncertainties in future spatial patterns of conservation‐related outcomes make it difficult to implement standard conservation‐planning paradigms. A recent study translates Markowitz's risk‐diversification strategy from finance to conservation settings, enabling conservation agents to use this diversification strategy for allocating conservation and restoration investments across space to minimize the risk associated with such uncertainty. However, this method is information intensive and requires a large number of forecasts of ecological outcomes associated with possible climate‐change scenarios for carrying out fine‐resolution conservation planning. We developed a technique for iterative, spatial portfolio analysis that can be used to allocate scarce conservation resources across a desired level of subregions in a planning landscape in the absence of a sufficient number of ecological forecasts. We applied our technique to the Prairie Pothole Region in central North America. A lack of sufficient future climate information prevented attainment of the most efficient risk‐return conservation outcomes in the Prairie Pothole Region. The difference in expected conservation returns between conservation planning with limited climate‐change information and full climate‐change information was as large as 30% for the Prairie Pothole Region even when the most efficient iterative approach was used. However, our iterative approach allowed finer resolution portfolio allocation with limited climate‐change forecasts such that the best possible risk‐return combinations were obtained. With our most efficient iterative approach, the expected loss in conservation outcomes owing to limited climate‐change information could be reduced by 17% relative to other iterative approaches. 相似文献
602.
BEN C. SCHEELE DAVID A. HUNTER LAURA F. GROGAN LEE BERGER JON E. KOLBY MICHAEL S. MCFADDEN GERRY MARANTELLI LEE F. SKERRATT DON A. DRISCOLL 《Conservation biology》2014,28(5):1195-1205
Wildlife diseases pose an increasing threat to biodiversity and are a major management challenge. A striking example of this threat is the emergence of chytridiomycosis. Despite diagnosis of chytridiomycosis as an important driver of global amphibian declines 15 years ago, researchers have yet to devise effective large‐scale management responses other than biosecurity measures to mitigate disease spread and the establishment of disease‐free captive assurance colonies prior to or during disease outbreaks. We examined the development of management actions that can be implemented after an epidemic in surviving populations. We developed a conceptual framework with clear interventions to guide experimental management and applied research so that further extinctions of amphibian species threatened by chytridiomycosis might be prevented. Within our framework, there are 2 management approaches: reducing Batrachochytrium dendrobatidis (the fungus that causes chytridiomycosis) in the environment or on amphibians and increasing the capacity of populations to persist despite increased mortality from disease. The latter approach emphasizes that mitigation does not necessarily need to focus on reducing disease‐associated mortality. We propose promising management actions that can be implemented and tested based on current knowledge and that include habitat manipulation, antifungal treatments, animal translocation, bioaugmentation, head starting, and selection for resistance. Case studies where these strategies are being implemented will demonstrate their potential to save critically endangered species. Intervenciones para Reducir el Riesgo de Extinción en Anfibios Amenazados por la Quitridiomicosis 相似文献
603.
Solar energy conversion into electricity by photovoltaic modules is now a mature technology. We discuss the need for materials and device developments using conventional silicon and other materials, pointing to the need to use scalable materials and to reduce the energy payback time. Storage of solar energy can be achieved using the energy of light to produce a fuel. We discuss how this can be achieved in a direct process mimicking the photosynthetic processes, using synthetic organic, inorganic, or hybrid materials for light collection and catalysis. We also briefly discuss challenges and needs for large-scale implementation of direct solar fuel technologies. 相似文献
604.
Jennifer M. Sanders C. Rhett Jackson Meredith Welch-Devine 《Journal of the American Water Resources Association》2023,59(4):803-823
Despite long-standing knowledge of the benefits of riparian buffers for mitigating nonpoint source pollution, many streams are unprotected by buffers. Even landowners who understand ecological values of buffers mow riparian vegetation to the streambank. Do trends in rural riparian conditions reflect the development of riparian forest science? What motivates residential riparian management actions? Using high-resolution orthoimagery, we quantified riparian conditions and trends between 1998 and 2015 in the rural upper Little Tennessee River basin in Macon County, North Carolina and explored how landowners view riparian zone management and riparian restoration programs. Buffer composition in 2015 was as follows: no buffer (32.5%), narrow (19.3%), forested (26.7%), shrub (7.2%), and intermediate (7.0%). Relative to 1998, the greatest decrease occurred in the no buffer class (−17.7%, 46 km) and the largest increases occurred in the shrub (+72.5%, 20 km) and narrow (12.6%, 14 km) classes. Forested buffer marginally increased. Semi-structured interview data suggest that landowners prioritize recreational and scenic aspects of riparian buffers over ecological functions such as filtration and bank stabilization. Riparian restoration programs might be made more enticing to non-adopters if outreach language appealed to landowner priorities, design elements demonstrated intentional management, and program managers highlighted areas where ecological goals and landowner values align. 相似文献
605.
Understanding and encouraging greater nature engagement in Australia: results from a national survey 总被引:1,自引:0,他引:1
Interaction with nature has a range of significant health, ecological and economic benefits and a number of governments are implementing policies to increase humans’ engagement with nature. Using a large nationally representative survey sample in Australia, this study provides a detailed comment on the feasibility of such a policy, as well as contributing to an understanding of the characteristics of individuals who engaged in one or more of five dimensions of nature interaction, namely: nature engagement; conservation participation; nature advocacy; environmentally friendly purchasing and future engagement with nature conservation. The results indicate that age, income, education, marital status and household structure are all important influences on various types of nature engagement. It is suggested that increasing opportunities for young people to interact with nature is important, as well as supporting older people's involvement in conservation, plus focusing on the need to target and direct various policies. 相似文献
606.
The Southern Ocean is one of the most rapidly changing ecosystems on the planet due to the effects of climate change and commercial fishing for ecologically important krill and fish. Because sea ice loss is expected to be accompanied by declines in krill and fish predators, decoupling the effects of climate and anthropogenic changes on these predator populations is crucial for ecosystem‐based management of the Southern Ocean. We reviewed research published from 2007 to 2014 that incorporated very high‐resolution satellite imagery to assess distribution, abundance, and effects of climate and other anthropogenic changes on populations of predators in polar regions. Very high‐resolution imagery has been used to study 7 species of polar animals in 13 papers, many of which provide methods through which further research can be conducted. Use of very high‐resolution imagery in the Southern Ocean can provide a broader understanding of climate and anthropogenic forces on populations and inform management and conservation recommendations. We recommend that conservation biologists continue to integrate high‐resolution remote sensing into broad‐scale biodiversity and population studies in remote areas, where it can provide much needed detail. Aplicaciones de Imágenes de Muy Alta Resolución en el Estudio y Conservación de Grandes Depredadores en el Océano Antártico 相似文献
607.
We analyze the impact of ratification constraints on the optimal terms of international environmental agreements (IEAs). For this, we combine the literature on IEAs with the public choice literature on two-level games. By also incorporating uncertain preferences of the pivotal voter in the ratification stage, we make several important contributions: (i) we contribute to a more realistic modeling of the temporal structure of international agreements, (ii) we show a surprising, yet intuitive non-monotonic relationship between the optimal commitment level and the variance of ratification decisions, (iii) we identify reasons to expect a larger number of countries to join international negotiations than predicted by most of the coalition formation literature based on a representative agent model. Ratification constraints thereby can improve the welfare gains from stable international agreements. 相似文献
608.
Aarin Teague Philip B. Bedient Birnur Guven 《Journal of the American Water Resources Association》2011,47(3):620-634
Teague, Aarin, Philip B. Bedient, and Birnur Guven, 2011. Targeted Application of Seasonal Load Duration Curves Using Multivariate Analysis in Two Watersheds Flowing Into Lake Houston. Journal of the American Water Resources Association (JAWRA) 47(3):620‐634. DOI: 10.1111/j.1752‐1688.2011.00529.x Abstract: Water quality is a problem in Lake Houston, the primary source of drinking water for the City of Houston, Texas, due to pollutant loads coming from the influent watersheds, including Spring Creek and Cypress Creek. Statistical analysis of the historic water quality data was developed to understand the source characterization and seasonality of the watershed. Multivariate analysis including principal component, cluster, and discriminant analysis provided a custom seasonal assessment of the watersheds so that loading curves may be targeted for season specific pollutant source characterization. The load duration curves have been analyzed using data collected by the U.S. Geologic Survey with corresponding City of Houston water quality data at the sites to characterize the behavior of the pollutant sources and watersheds. Custom seasons were determined for Spring Creek and Cypress Creek watersheds and pollutant source characterization compared between the seasons and watersheds. 相似文献
609.
AYESHA I. T. TULLOCH VIVITSKAIA J. D. TULLOCH MEGAN C. EVANS MORENA MILLS 《Conservation biology》2014,28(6):1462-1473
Understanding the social dimensions of conservation opportunity is crucial for conservation planning in multiple‐use landscapes. However, factors that influence the feasibility of implementing conservation actions, such as the history of landscape management, and landholders’ willingness to engage are often difficult or time consuming to quantify and rarely incorporated into planning. We examined how conservation agencies could reduce costs of acquiring such data by developing predictive models of management feasibility parameterized with social and biophysical factors likely to influence landholders’ decisions to engage in management. To test the utility of our best‐supported model, we developed 4 alternative investment scenarios based on different input data for conservation planning: social data only; biological data only; potential conservation opportunity derived from modeled feasibility that incurs no social data collection costs; and existing conservation opportunity derived from feasibility data that incurred collection costs. Using spatially explicit information on biodiversity values, feasibility, and management costs, we prioritized locations in southwest Australia to control an invasive predator that is detrimental to both agriculture and natural ecosystems: the red fox (Vulpes vulpes). When social data collection costs were moderate to high, the most cost‐effective investment scenario resulted from a predictive model of feasibility. Combining empirical feasibility data with biological data was more cost‐effective for prioritizing management when social data collection costs were low (<4% of the total budget). Calls for more data to inform conservation planning should take into account the costs and benefits of collecting and using social data to ensure that limited funding for conservation is spent in the most cost‐efficient and effective manner. 相似文献
610.
‘Bringing the state back in’ to research on comparative, inter-, and trans-national environmental politics and policy will contribute to better understanding of the limits and prospects of contemporary approaches to environmental politics and the overall evolution of contemporary states once environmental issues become central. The rationale for the state as an analytical perspective in environmental policy and politics is explained, and an empirically oriented concept of the environmental state is introduced, along with a tentative sketch of its evolution in historical perspective. A research agenda on the environmental state is mapped out, centring around variation and convergence in environmental states across space and time; the political/economic dynamics of contemporary environmental states; and inter-linkages among environmental problems, the constitution of political communities, and the functioning of the public power. In conclusion, the ways in which the contributions to this volume address that research agenda are introduced. 相似文献