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141.
Joslin L. Moore Abbey E. Camaclang Alana L. Moore Cindy E. Hauser Michael C. Runge Victor Picheny Libby Rumpff 《Conservation biology》2021,35(5):1639-1649
Land managers decide how to allocate resources among multiple threats that can be addressed through multiple possible actions. Additionally, these actions vary in feasibility, effectiveness, and cost. We sought to provide a way to optimize resource allocation to address multiple threats when multiple management options are available, including mutually exclusive options. Formulating the decision as a combinatorial optimization problem, our framework takes as inputs the expected impact and cost of each threat for each action (including do nothing) and for each overall budget identifies the optimal action to take for each threat. We compared the optimal solution to an easy to calculate greedy algorithm approximation and a variety of plausible ranking schemes. We applied the framework to management of multiple introduced plant species in Australian alpine areas. We developed a model of invasion to predict the expected impact in 50 years for each species-action combination that accounted for each species’ current invasion state (absent, localized, widespread); arrival probability; spread rate; impact, if present, of each species; and management effectiveness of each species-action combination. We found that the recommended action for a threat changed with budget; there was no single optimal management action for each species; and considering more than one candidate action can substantially increase the management plan's overall efficiency. The approximate solution (solution ranked by marginal cost-effectiveness) performed well when the budget matched the cost of the prioritized actions, indicating that this approach would be effective if the budget was set as part of the prioritization process. The ranking schemes varied in performance, and achieving a close to optimal solution was not guaranteed. Global sensitivity analysis revealed a threat's expected impact and, to a lesser extent, management effectiveness were the most influential parameters, emphasizing the need to focus research and monitoring efforts on their quantification. 相似文献
142.
随着农村地区生活水平的提升,生活污水所含污染物成分趋于复杂化,未经处理就地排放对生态环境影响不容小觑。目前,农村生活污水治理模式种类多样,但决策方法缺乏科学依据。以内蒙古地区82个村落为研究对象。以自然村落为最小研究单元,利用村落宅基地占比、村落长宽比、周长、极限距离、坡度0°~8°占比和坡度标准差等指标,构建了居住密度决策树 (准确率76%) 以及地势决策树 (准确率88%) 。决策树所得结果通过二分类概率单位回归 (Probit)分析 (准确率87%) ,确定其村落集中或分散情况,进而选择适宜的村落污水治理模式 (集中模式、纳管模式、分散模式、拉运模式、就地利用模式) 。农村生活污水治理模式决策方法的确立决策指标的量化,为促进农村生活污水治理体系的发展、提升污水治理的有效性具有积极意义。 相似文献
143.
苯胺所造成的环境污染问题日益严重,如何正确地选择处理处置技术,对降低化学品所造成的影响有着极其重要的意义。为了在事故发生后能够最短时间内有效地消除污染物对环境的影响,选取最适合的处理处置技术,提出了苯胺污染事故处理处置技术评估指标体系,从技术性能、经济成本、环境影响和社会影响4个方面进行了评估指标选取;另外,采用基于群决策的层次分析法(AHP)进行了数据处理,以降低评估过程中专家的主观性对评估结果的影响,结合评分标准最终获得最佳的应急处理处置技术方案,可为苯胺环境污染事故应急预案的制定与事故应急处理处置技术的选取提供参考。 相似文献
144.
JULIEN MARTIN PAUL L. FACKLER JAMES D. NICHOLS MICHAEL C. RUNGE CAROL L. McINTYRE BRUCE L. LUBOW MAGGIE C. McCLUSKIE JOEL A. SCHMUTZ 《Conservation biology》2011,25(2):316-323
Abstract: Unintended effects of recreational activities in protected areas are of growing concern. We used an adaptive‐management framework to develop guidelines for optimally managing hiking activities to maintain desired levels of territory occupancy and reproductive success of Golden Eagles (Aquila chrysaetos) in Denali National Park (Alaska, U.S.A.). The management decision was to restrict human access (hikers) to particular nesting territories to reduce disturbance. The management objective was to minimize restrictions on hikers while maintaining reproductive performance of eagles above some specified level. We based our decision analysis on predictive models of site occupancy of eagles developed using a combination of expert opinion and data collected from 93 eagle territories over 20 years. The best predictive model showed that restricting human access to eagle territories had little effect on occupancy dynamics. However, when considering important sources of uncertainty in the models, including environmental stochasticity, imperfect detection of hares on which eagles prey, and model uncertainty, restricting access of territories to hikers improved eagle reproduction substantially. An adaptive management framework such as ours may help reduce uncertainty of the effects of hiking activities on Golden Eagles. 相似文献
145.
Indicators and indices are important tools that assist decision makers to formulate and implement plans for management at local, national and international levels. Four indicators for hazardous waste management are described that have recently been adopted within the United Nations framework of Indicators of Sustainable Development. Although these four indicators will be useful tools, the need for a broader range of policy-relevant qualitative and quantitative indicators, proxy indicators and indices is outlined. The argument is advanced that in order for all nations to better manage the range of hazardous waste issues, including waste generation, export/import and disposal, a set of innovative indicators and indices is required. Useful indicators and indices are described that could be used to link and quantify likely environmental, ecosystem and health impacts and risks especially from hazardous waste disposal. Indicators are also suggested that could be used to illustrate the shift in industrial strategy away from end-of-pipe processes towards waste recycling, cleaner production and integrated life-cycle analysis. It was concluded that until the lack of reliable and harmonized data on hazardous waste is addressed, indicator development and use by national and international decision makers cannot readily be implemented. 相似文献
146.
147.
采集了停车场、道路旁、居民区及产业园区4种不同用地类型的生物滞留设施的0~10 cm表层土壤,分析了8种重金属污染物(As、 Hg、 Cd、 Cr、 Pb、 Cu、 Ni和Zn)的累积含量,并对重金属累积的影响因素、污染水平、潜在生态风险和人体健康风险进行了分析和评估.结果表明,8种重金属污染物的累积含量存在较大的差异,ω(As)、ω(Hg)、ω(Cd)、ω(Cr)、ω(Pb)、ω(Cu)、ω(Ni)和ω(Zn)的平均值分别为8.92、 0.25、 0.10、 31.56、 14.81、 21.27、 23.69和62.75 mg·kg-1, As和Hg的含量平均值分别达到了土壤背景值的1.26和5.21倍;相关性分析表明,8种重金属含量均与土壤有机质含量呈现较强正相关,除Hg之外均与土壤pH值呈现正相关,除As外与磷含量呈现正相关.内梅罗综合指数以及潜在生态风险指数的分析结果表明,除Hg之外的其他7种重金属的污染水平及生态风险较低,受Hg污染的影响,生物滞留设施重金属综合污染水平以及生态风险较高,Hg对土壤环境存在一定的潜在威胁.4类设施重金属非致癌风险在可接受... 相似文献
148.
为最小化灾后配电网损失量,准确描述完整维修队工作时间(分为路途时间与具体维修时间),依据台风路径对维修队所需路途时间进行分类,并利用期望概率描述具体维修时间的不确定性。建立2阶段分布式鲁棒优化模型,采用CCG算法分析国内某地区配电网算例发现:考虑维修时间不确定性可以有效减少配电网损失量。 相似文献
149.
150.