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Quantitative tools for implementing the new definition of significant portion of the range in the U.S. Endangered Species Act 下载免费PDF全文
Julia E. Earl Sam Nicol Ruscena Wiederholt Jay E. Diffendorfer Darius Semmens D. T. Tyler Flockhart Brady J. Mattsson Gary McCracken D. Ryan Norris Wayne E. Thogmartin Laura López‐Hoffman 《Conservation biology》2018,32(1):35-49
In 2014, the Fish and Wildlife Service (FWS) and National Marine Fisheries Service announced a new policy interpretation for the U.S. Endangered Species Act (ESA). According to the act, a species must be listed as threatened or endangered if it is determined to be threatened or endangered in a significant portion of its range (SPR). The 2014 policy seeks to provide consistency by establishing that a portion of the range should be considered significant if the associated individuals’ “removal would cause the entire species to become endangered or threatened.” We reviewed 20 quantitative techniques used to assess whether a portion of a species’ range is significant according to the new guidance. Our assessments are based on the 3R criteria—redundancy (i.e., buffering from catastrophe), resiliency (i.e., ability to withstand stochasticity), and representation (i.e., ability to evolve)—that the FWS uses to determine if a species merits listing. We identified data needs for each quantitative technique and considered which methods could be implemented given the data limitations typical of rare species. We also identified proxies for the 3Rs that may be used with limited data. To assess potential data availability, we evaluated 7 example species by accessing data in their species status assessments, which document all the information used during a listing decision. In all species, an SPR could be evaluated with at least one metric for each of the 3Rs robustly or with substantial assumptions. Resiliency assessments appeared most constrained by limited data, and many species lacked information on connectivity between subpopulations, genetic variation, and spatial variability in vital rates. These data gaps will likely make SPR assessments for species with complex life histories or that cross national boundaries difficult. Although we reviewed techniques for the ESA, other countries require identification of significant areas and could benefit from this research. 相似文献
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Edel Pérez-López Tyler Wist Yesenia Rodríguez Mauricio Luna-Rodríguez Chrystel Y. Olivier 《Environment, Development and Sustainability》2018,20(4):1797-1805
Native corn in Mexico can be affected by maize bushy stunt disease (MBS), which can negatively impact maize-farming operations. Maize bushy stunt symptoms in native corn were linked to the presence of phytoplasmas through molecular analysis of symptomatic native corn plants in Mexico. These findings motivated a socioeconomic characterization and identification of the management strategies developed by the “subsistence farmers” of those communities to answer the questions: What elements of farming affect the presence of MBS disease in “subsistence farmers” fields? What do “subsistence farmers” know about MBS disease and the pathogen associated with MBS disease? How best can MBS disease be managed in small farming communities in Mexico? Through face-to-face interviews with growers and the corresponding analyses of their responses, we identified a widespread lack of knowledge about MBS disease, its causal agent and its vector(s). This study highlighted factors useful to guide future management decisions and education programs, as well as further research to transmit information about MBS disease among “subsistence farmers” in rural communities in Mexico. 相似文献
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Carmelo J. León 《Journal of Environmental Planning and Management》2016,59(4):687-707
Climate change policies can compete with policies on other social and environmental problems for limited economic resources. This paper investigates the potential influence of alternative policies on citizens’ preferences for climate change policies. A contingent valuation study was implemented to estimate the impact of observable and unobservable contextual effects of competing polices on climate change valuation. Individuals are also investigated about their endowment of knowledge and emotional reactions to such problems. The results show that citizens’ valuation of climate change policies crucially depends on the context-dependent competing policies. The valuation rises as the number of competing policies increases. This increment becomes economically significant when the competing policies are related to specific problems such as forest fires and development. In addition, the valuation also rises with the amount of knowledge endowed by the individual about the climate change problem, and with the experience of negative emotions such as fear and sadness. 相似文献
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Emilio Galdeano-Gómez Juan Carlos Pérez-Mesa Ángeles Godoy-Durán 《Sustainability Science》2016,11(2):349-362
The social pillar has often been treated as an ‘add on’ in sustainable development studies, and analyses of its ‘proactivity’ in economic, environmental, and social transformations to sustainability outcomes are scant. The present paper looks at the social dimension as a key driver of sustainable development. Social factors in the farming system in southeast Spain are analyzed to show how family farms and their networks can integrate socio-economic and eco-social goals, promoting the generation of synergies and trade-offs between the dimensions of sustainability. This study contributes to existing debate on the role of family farms in the framework of European rural development. 相似文献
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Soran Maria-Loredana Opriş Ocsana Lung Ildikó Kacso Irina Porav Alin S. Stan Manuela 《Environmental science and pollution research international》2017,24(19):16396-16406
Environmental Science and Pollution Research - In the recent years, residual antibiotics are considered to be emerging environmental pollutants due to their continuous input and persistence into... 相似文献