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191.
Nathan J. Bennett Robin Roth Sarah C. Klain Kai M. A. Chan Douglas A. Clark Georgina Cullman Graham Epstein Michael Paul Nelson Richard Stedman Tara L. Teel Rebecca E. W. Thomas Carina Wyborn Deborah Curran Alison Greenberg John Sandlos Diogo Veríssimo 《Conservation biology》2017,31(1):56-66
Despite broad recognition of the value of social sciences and increasingly vocal calls for better engagement with the human element of conservation, the conservation social sciences remain misunderstood and underutilized in practice. The conservation social sciences can provide unique and important contributions to society's understanding of the relationships between humans and nature and to improving conservation practice and outcomes. There are 4 barriers—ideological, institutional, knowledge, and capacity—to meaningful integration of the social sciences into conservation. We provide practical guidance on overcoming these barriers to mainstream the social sciences in conservation science, practice, and policy. Broadly, we recommend fostering knowledge on the scope and contributions of the social sciences to conservation, including social scientists from the inception of interdisciplinary research projects, incorporating social science research and insights during all stages of conservation planning and implementation, building social science capacity at all scales in conservation organizations and agencies, and promoting engagement with the social sciences in and through global conservation policy‐influencing organizations. Conservation social scientists, too, need to be willing to engage with natural science knowledge and to communicate insights and recommendations clearly. We urge the conservation community to move beyond superficial engagement with the conservation social sciences. A more inclusive and integrative conservation science—one that includes the natural and social sciences—will enable more ecologically effective and socially just conservation. Better collaboration among social scientists, natural scientists, practitioners, and policy makers will facilitate a renewed and more robust conservation. Mainstreaming the conservation social sciences will facilitate the uptake of the full range of insights and contributions from these fields into conservation policy and practice. 相似文献
192.
An analysis of tritium and 36Cl data collected at Yucca Mountain, Nevada suggests that fracture flow may occur at high velocities through the thick unsaturated zone. The mechanisms and extent of this “fast flow” in fractures at Yucca Mountain are investigated with data analysis, mixing models and several one-dimensional modeling scenarios. The model results and data analysis provide evidence substantiating the weeps model [Gauthier, J.H., Wilson, M.L., Lauffer, F.C., 1992. Proceedings of the Third Annual International High-level Radioactive Waste Management Conference, vol. 1, Las Vegas, NV. American Nuclear Society, La Grange Park, IL, pp. 891–989] and suggest that fast flow in fractures with minimal fracture–matrix interaction may comprise a substantial proportion of the total infiltration through Yucca Mountain. Mixing calculations suggest that bomb-pulse tritium measurements, in general, represent the tail end of travel times for thermonuclear-test-era (bomb-pulse) infiltration. The data analysis shows that bomb-pulse tritium and 36Cl measurements are correlated with discrete features such as horizontal fractures and areas where lateral flow may occur. The results presented here imply that fast flow in fractures may be ubiquitous at Yucca Mountain, occurring when transient infiltration (storms) generates flow in the connected fracture network. 相似文献
193.
Abstract: Marking animals so that they are uniquely identifiable provides information that may assist conservation efforts. Nevertheless, some methods used to mark animals can be harmful. We used mathematical methods to assess the trade‐off between the impact of marking threatened species and the value of the information gained. We considered the case where 2 management strategies, each aiming to improve a species' survival rate, are implemented in an experimental phase. The results of the experiment were applied in a postexperimental management phase. We expressed the expected number of survivors in both phases mathematically, accounting for any mortality caused by the experiment, and determined the proportion of animals to mark to maximize this number. The optimal number of animals to mark increased with the number of individuals available for the experiment and with the number of individuals to be managed in the future. The optimal solution was to mark only 25% of the animals when there were 1000 individuals available for the experiment, the results were used to manage 2000 individuals, and marking caused mortality of 1%. Fewer animals were marked when there were fewer animals in either phase or when marking caused higher mortality. In the case of the Helmeted Honeyeater (Lichenostomus melanops cassidix), the optimal proportion to mark was <1 if the mortality rate was >0.15%–1%, with the threshold depending on the number of animals in the experimental and postexperimental phases. The trade‐off between gaining more information about a species and possibly harming individuals of that species by marking them is difficult to assess subjectively. We show how to determine objectively the optimal proportion of animals to mark to enhance the management of threatened species. 相似文献
194.
KAREN L. POPE 《Conservation biology》2008,22(6):1572-1581
Abstract: Sport‐fish introductions are now recognized as an important cause of amphibian decline, but few researchers have quantified the demographic responses of amphibians to current options in fisheries management designed to minimize effects on sensitive amphibians. Demographic analyses with mark–recapture data allow researchers to assess the relative importance of survival, local recruitment, and migration to changes in population densities. I conducted a 4‐year, replicated whole‐lake experiment in the Klamath Mountains of northern California (U.S.A.) to quantify changes in population density, survival, population growth rate, and recruitment of the Cascades frog (Rana cascadae) in response to manipulations of non‐native fish populations. I compared responses of the frogs in lakes where fish were removed, in lakes in their naturally fish‐free state, and in lakes where fish remained that were either stocked annually or no longer being stocked. Within 3 years of fish removals from 3 lakes, frog densities increased by a factor of 13.6. The survival of young adult frogs increased from 59% to 94%, and realized population growth and recruitment rates at the fish‐removal lakes were more than twice as high as the rates for fish‐free reference lakes and lakes that contained fish. Population growth in the fish‐removal lakes was likely due to better on‐site recruitment of frogs to later life stages rather than increased immigration. The effects on R. cascadae of suspending stocking were ambiguous and suggested no direct benefit to amphibians. With amphibians declining worldwide, these results show that active restoration can slow or reverse the decline of species affected by fish stocking within a short time frame. 相似文献
195.
This study examines urban pollution within Derechos Humanos, a colonia popular in Matamoros, Tamaulipas, Mexico. General water quality indicators (coliform bacteria, total dissolved solids, ecologically relevant cations and anions), heavy metals (copper, lead, nickel, zinc, iron and cadmium), and volatile organic compounds (benzene, toluene, ethylbenzene, styrene, and dichlorobenzene and xylene isomers) were quantified within a wastewater canal running adjacent to the community. Water samples were collected at multiple sites along the banks of the canal and evidence of anthropogenic emissions existed at each sampling location. Sample site 2, approximately 10 m upstream of the colonia, contained both the widest range of hazardous pollutants and the greatest number exceeding US Environmental Protection Agency surface water standards. At each sampling location, high concentrations of total coliform (> 10(4) colonies/100 mL sample), lead (ranging from 0.05 to 0.40 mg/L), nickel (levels from 0.21 to 1.45 mg/L), and benzene (up to 9.80 mg/L) were noted. 相似文献
196.
Contingent valuation methods were used to derive an economic value for salmonid spawning habitat restoration. Anglers' willingness to pay for such restoration and farmers' willingness to accept compensation for lost productivity due to the restoration were investigated using questionnaire and face-to-face surveys, respectively. These elements were combined with the Wye Habitat Improvement Project (WHIP) budget into a cost-benefit analysis (CBA) based upon direct use values only. The CBA assumed that the WHIP will improve salmonid stock. Different levels of investment were considered and the CBA gave a positive net present value indicating an economically viable project and benefit-to-cost ratios greater than one for minor projects. However, the number of anglers using the Wye would need to double or triple in order to justify the full WHIP budget. Management of an environmental resource must consider users' and stakeholders' needs and opinions. It was found that anglers on the Wye value habitat/scenery in its own right and that this played an important part in the activity. Farmers' agreement regarding involvement in such projects was more likely to be determined by their political and ethical views than receiving an economic compensation. 相似文献
197.
Weng Q 《Journal of environmental management》2007,85(4):1048-1062
Three innovations in water and soil conservancy technology in the Pearl River Delta of South China, i.e., dike building, land reclamation, and dike-pond systems, were examined from a historical perspective. They were found to best reflect local farmers' efforts to cope with the challenges of various water disasters and to build a harmonious relationship with the changed environment. These technologies were critical to the agricultural success and sustainability over the past 2000 years, and reflected local farmers' wisdom in balancing land use and environmental conservation. Imprudent use of a new agricultural technology could damage the environment, and could disturb the human-environment relationship, as evidenced by the more frequent flooding that followed inappropriate dike building and premature reclamation. It is suggested that as the urbanization and industrialization process in the delta region continues, the kind of thinking that made the water and soil conservancy sustainable needs to be incorporated into the design of similar technologies for water use and river basin management today. 相似文献
198.
环境保护部日前发布((2013年中国机动车污染防治年报》,公布了2012年全国机动车污染排放状况。本期“研究成果展示”专栏以六篇形式连载。本文刊载2012年全国机动车污染物排放量现状及其变化趋势的内容,以飨读者。该年报指出,2012年,全国机动车排放污染物4612.1万吨,比2011年增加0.1%,其中氮氧化物(NOx)640.0万吨,碳氢化合物(HC)438.2万吨,一氧化碳(CO)3471.7万吨,颗粒物(PM)62.2万吨。汽车是污染物总量的主要贡献者,其排放的NOx和PM超过90%,HC和CO超过70%。按车型分类,全国货车排放的NOx和PM明显高于客车,其中重型货车是主要贡献者;而客车CO和HC排放量则明显高于货车。按燃料分类,全国柴油车排放的NOx接近汽车排放总量的70%,PM超过90%;而汽油车CO和HC排放量则较高,超过排放总量的70%。按排放标准分类,占汽车保有量7.8%的国I前标准汽车,其排放的四种主要污染物占排放总量的35.0%以上:而占保有量61.6%的国Ⅲ及以上标准汽车,其排放量还不到排放总量的30.0%。按环保标志分类,仅占汽车保有量13.4%的“黄标车”却排放了58.2%的NOx、56.8%的Hc、52.5%的CO和81.9%的PM。2012年,全国机动车保有量比2011年增长了7.8%,但四项污染物排放总量与2011年基本持平,这与实施更严格的机动车排放标准、加快淘汰高排放的“黄标车”、提升车用燃料品质等措施有关。 相似文献
199.
Wrestling with the complexity of evaluation for organizations at the boundary of science,policy, and practice
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R. Pitt C. Wyborn G. Page J. Hutton M. Virah Sawmy M. Ryan L. Gallagher 《Conservation biology》2018,32(5):998-1006
Boundary organizations are situated between science, policy, and practice and have a goal of supporting communication and collaboration among these sectors. They have been promoted as a way to improve the effectiveness of conservation efforts by building stronger relationships between scientists, policy makers, industry, and practitioners (Cook et al. 2013). Although their promise has been discussed in theory, the work of and expectations for boundary organizations are less defined in practice. Biodiversity conservation is characterized by complexity, uncertainty, dissent, and tight budgets, so boundary organizations face the challenging task of demonstrating their value to diverse stakeholders. We examined the challenges boundary organizations face when seeking to evaluate their work and thus aimed to encourage more productive conversations about evaluation of boundary organizations and their projects. Although no off‐the‐shelf solution is available for a given boundary organization, we identified 4 principles that will support effective evaluation for boundary organizations: engage diverse stakeholders, support learning and reflection, assess contribution to change, and align evaluation with assumption and values. 相似文献
200.
Standardized reporting of the costs of management interventions for biodiversity conservation
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Gwenllian D. Iacona William J. Sutherland Bonnie Mappin Vanessa M. Adams Paul R. Armsworth Tim Coleshaw Carly Cook Ian Craigie Lynn V. Dicks James A. Fitzsimons Jennifer McGowan Andrew J. Plumptre Tal Polak Andrew S. Pullin Jeremy Ringma Ian Rushworth Andrea Santangeli Annette Stewart Ayesha Tulloch Jessica C. Walsh Hugh P. Possingham 《Conservation biology》2018,32(5):979-988
Effective conservation management interventions must combat threats and deliver benefits at costs that can be achieved within limited budgets. Considerable effort has focused on measuring the potential benefits of conservation interventions, but explicit quantification of the financial costs of implementation is rare. Even when costs have been quantified, haphazard and inconsistent reporting means published values are difficult to interpret. This reporting deficiency hinders progress toward a collective understanding of the financial costs of management interventions across projects and thus limits the ability to identify efficient solutions to conservation problems or attract adequate funding. We devised a standardized approach to describing financial costs reported for conservation interventions. The standards call for researchers and practitioners to describe the objective and outcome, context and methods, and scale of costed interventions, and to state which categories of costs are included and the currency and date for reported costs. These standards aim to provide enough contextual information that readers and future users can interpret the cost data appropriately. We suggest these standards be adopted by major conservation organizations, conservation science institutions, and journals so that cost reporting is comparable among studies. This would support shared learning and enhance the ability to identify and perform cost‐effective conservation. 相似文献