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991.
Lauren L. Sullivan Matthew J. Michalska-Smith Katie P. Sperry David A. Moeller Allison K. Shaw 《Conservation biology》2021,35(3):944-954
Habitat loss and fragmentation can negatively influence population persistence and biodiversity, but the effects can be mitigated if species successfully disperse between isolated habitat patches. Network models are the primary tool for quantifying landscape connectivity, yet in practice, an overly simplistic view of species dispersal is applied. These models often ignore individual variation in dispersal ability under the assumption that all individuals move the same fixed distance with equal probability. We developed a modeling approach to address this problem. We incorporated dispersal kernels into network models to determine how individual variation in dispersal alters understanding of landscape-level connectivity and implemented our approach on a fragmented grassland landscape in Minnesota. Ignoring dispersal variation consistently overestimated a population's robustness to local extinctions and underestimated its robustness to local habitat loss. Furthermore, a simplified view of dispersal underestimated the amount of habitat substructure for small populations but overestimated habitat substructure for large populations. Our results demonstrate that considering biologically realistic dispersal alters understanding of landscape connectivity in ecological theory and conservation practice. 相似文献
992.
993.
Socio-environmental conflict in the construction of a power plant in Spain's Basque Country: strategies,expertise and certifications 总被引:1,自引:0,他引:1
Gloria Baigorrotegui 《Local Environment》2015,20(1):114-129
Social and anthropological studies show a growing number of conflicts surrounding energy projects, as governments and companies insist on their implementation despite the concerns of local actors about their perceived socio-environmental risks. In this context, the purpose of this paper is to analyse the politicisation of expertise and certifications in a conflict over the construction of a combined cycle power plant by linking strategic assumptions from two particular sociological approaches. The first approach is based on the study of frame alignment in social movement organisations and the second on the translating interests in actor–network theory. These linked premises are examined in the conflict arising from the construction of a combined cycle natural gas plant in Boroa, in the Basque Country of Spain. This case study brings to light interesting findings on the strategies of the different agencies, certifications, politicisation of expertise and the increasing hostility in local conflicts. 相似文献
994.
飞行员安全能力是飞行员排班、机组搭配、掌握飞行员安全状态的重要依据,为客观、准确地对飞行员安全能力进行评价,对安全管理能力内涵进行了界定,找到了评价飞行员安全能力的4个二级指标,共17个三级指标。后来用网络层次分析法(ANP)对各影响因素的影响力进行排序,确定了指标的综合权重。综合考虑飞行员安全能力各影响因素之间的不确定性、模糊性,采用集对分析方法(SPA)进行评价。最后将集对分析法和网络层次分析结合构建的评价模型运用于某航空公司飞行员安全能力评价,结果与实际情况基本一致,说明了该方法的有效性。 相似文献
995.
文章在前人研究的基础上,根据感潮河网地区水体的水动力、水质特性,建立了河网一雏水动力和水质模型,并进行了模型验证。结果表明水动力模型计算值能够较好的吻合实洲值,能正确反映涨落潮趋势,水质模型能正确反映污染物受涨落潮影响在河网内回荡的变化情况。本研究成果对解决福州市水环境问题提供了一定的理论基础,具有一定的指导意义。 相似文献
996.
低碳化已成为物流未来发展的趋势,物流发达国家已经推进了低碳化进程并形成了可供借鉴的经验.综观中国物流业,低碳政策与法规不健全、低碳管理能力还有待提高、低碳技术尚需进一步研发、低碳意识和低碳人才培养要加强.在诸多因素制约下,只有政府、物流企业及相关协会组织、教育机构和社会各界共同努力,保持科学发展的态度、积极研发和掌握低碳物流新技术、培养合格的物流人才进行管理,才能将物流业低碳化早日实现. 相似文献
997.
Abstract: The brown tree snake ( Boiga irregularis ) is a devastating invader that has ecologically and economically affected Guam and is poised to disperse further. Interdiction efforts are being conducted on Guam and some of the potential receiving sites, but no tools exist for evaluating the potential for snake incursion; thus, the amount of effort that should be invested in protecting particular sites is unknown. We devised a model that predicts the relative risk of establishment of the brown tree snake (BTS) at a given site. To calculate overall risk, we incorporated in the model information on the likelihood of an organism entering the transportation system, avoiding detection, surviving to arrive at another location, and establishing at the receiving end. On the basis of documented rates of snake arrival at receiving sites, the model produced realistic predictions of invasion risk. Model outputs can thus be used to prioritize interdiction efforts to focus on especially vulnerable receiving locations. We provide examples of the utility of the model in evaluating the impacts of changes in transportation parameters. Finally, the model can be used to evaluate the impacts that BTS establishment at an additional site and that creation of a new source of snakes would have. The use of qualitative inputs allows the model to be adapted by substituting data on other invasive species or transportation systems. 相似文献
998.
Jiangwei WangSuqin Li Guohong Xiong Daqiang Cang 《Resources, Conservation and Recycling》2011,55(8):755-759
To improve the efficiency of water use and reuse, a digitalized water network system was implemented in a steel industrial complex. The system consisted of four parts: online instrument and sensing devices, programmable logic controller, data communication network and control center based on expert knowledge. The system achieved real-time monitoring, diagnosis, and early warning of cooling water system using data collected inline, and enabled data connectivity and transmission of self-developed software applications on personal computer. This research used a steel enterprise as a case study. After the analysis of its cooling water system and water-saving potential using water balance test, a digitalized water network was evaluated and implemented, and we believe this network can be suitable for steel industry in general. 相似文献
999.
Scholars have long stressed the need to bridge the gap between science and action and seek the most efficient use of knowledge for decision making. Many contributors have attempted to consider and understand the sociopolitical forces involved in knowledge generation and exchange. We argue, however, that a model is still needed to adequately conceptualize and frame the knowledge networks in which these processes are embedded. We devised a model for knowledge mapping as a prerequisite for knowledge management in the context of conservation. Using great ape conservation to frame our approach, we propose that knowledge mapping should be based on 2 key principles. First, each conservation network results from the conglomeration of subnetworks of expertise producing and using knowledge. Second, beyond the research-management gradient, other dimensions, such as the scale of operation, geographic location, and organizational characteristics, must also be considered. Assessing both knowledge production and trajectory across different dimensions of the network opens new space for investigating and reducing the gap between science and action. 相似文献
1000.
大力发展现代物流业和皖江城市带承接产业转移示范区建设是两大重要国家级战略.首先对轴—辐理论的国内外研究现状进行了总结和归纳,分析了轴—辐网络的结构及其优劣势.其次,设计了物流中心性指数的评价指标体系,运用主成分分析法对皖江城市带的9个地级城市进行物流节点等级划分,根据分析结果的总得分和区位特征确定合肥、芜湖、安庆3个一级物流节点,形成轴三角.分析了各级物流节点间的干线及支线物流通道,构建了皖江城市带轴—辐物流网络空间. 相似文献