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301.
鹞落坪自然保护区非使用价值的评估 总被引:1,自引:0,他引:1
选择鹞落坪自然保护区所在省份安徽省及其相邻省份江苏省,采用支付意愿法进行了支付意愿的问卷调查,对该保护区的非使用价值作定量评估。评估结果表明,鹞落坪自然保护区的非使用价值为198039.4万元·a-1,其中存在价值为106941.3万元·a-1,遗产价值为59411.8万元·a-1,选择价值为31686.3万元·a-1;江苏省和安徽省样本的平均支付意愿值(WTP)分别为42.0和14 4元·a-1;社会经济各因素与样本的支付意愿率及WTP之间的相关性在不同地区调查的结果有较大差异;对评估结果的敏感性分析显示,本次调查存在年龄和收入敏感性,存在教育程度不敏感性。 相似文献
302.
自然保护区管理有效性评价指标分析 总被引:5,自引:0,他引:5
根据154个国家级自然保护区的问卷调查结果,运用主成分分析法对26项管理评价指标进行分析,确定了影响保护区管理有效性的6个主要指标类体系。其结果表明:对管理有效性产生较大影响的主成分包括:物资保障、监控管理、经济开发收益、管理权归属、行政执法和交流合作。6个主成分对于管理有效性的贡献率比较分散,累计贡献率为68.671%;其中物资保障主成分贡献率最大,达26.011%。 相似文献
303.
基于IUCN保护区分类系统的中国自然保护区分类标准研究 总被引:2,自引:0,他引:2
在总结实施我国自然保护区分类标准的经验和问题的基础上,依据中国自然保护区建设的现状和特点,借鉴IUCN保护区分类系统,提出了中国新的自然保护区分类标准,并据此对已建自然保护区进行了重新分类,以期促进我国自然保护区建设管理工作以及国内外的信息交流。 相似文献
304.
Abstract: Recovery of endangered species in highly fragmented habitats often requires habitat restoration. Selection of restoration sites typically involves too many options and too much uncertainty to reach a decision based on existing reserve design methods. The Fender's blue butterfly ( Icaricia icarioides fenderi ) survives in small, isolated patches of remnant prairie in Oregon's Willamette Valley—a habitat for which <0.5% of the original remains. Recovery of this species will require considerable habitat restoration. We investigated the potential of biologically based rules of thumb and more complex models to serve as tools in making land acquisitions. Based on Fender's blue dispersal behavior and demography, we have estimated that restored patches should be <1 km from existing habitat and at least 2 ha. We compared these rules to the results of two modeling approaches: an incidence function model and a spatially explicit simulation of demography and dispersal behavior. Not surprisingly, the simple rules and complex models all conclude that large (>2 ha) connected (<1 km) patches have the highest restoration value. The dispersal model, however, suggests that small, connected patches have more restoration value than large, isolated patches, whereas the incidence function model suggests that size and connectivity are equally important. These differences stem from model assumptions. We used incidence functions to predict long-term, stochastic, steady-state conditions and dispersal simulations to predict short-term (25-year) colonization dynamics. To apply our results in the context of selecting restoration sites on the ground, we recommend selecting nearby sites when short-term colonization dynamics are expected to be an important aspect of a species' biology. 相似文献
305.
Effectiveness of Existing Reserves in the Long-Term Protection of a Regionally Rare Butterfly 总被引:3,自引:0,他引:3
DAVID GUTIÉRREZ 《Conservation biology》2005,19(5):1586-1597
306.
Stephanie A. Snyder Robert G. Haight Charles S. ReVelle 《Environmental Modeling and Assessment》2005,9(3):179-187
Conservation planners are called upon to make choices and trade-offs about the preservation of natural areas for the protection of species in the face of development pressures. We addressed the problem of selecting sites for protection over time with the objective of maximizing species representation, with uncertainty about future site development, and with periodic constraints on the number of sites that can be selected. We developed a 0–1, linear optimization model with 2 periods to select the sites that maximize expected species coverage subject to budget constraints. The model is based on the idea that development uncertainty can be characterized by a set of scenarios, each of which is a possible second-period development outcome for the set of sites. We also suggest that our 2-period model can be used in a sequential fashion that is consistent with adaptive planning. Results are presented for the Fox River watershed in Chicago. 相似文献
307.
Scott?A.?MalcolmaEmail author Charles?ReVelle 《Environmental Modeling and Assessment》2005,10(4):341-348
Models for designing habitat reserve networks have focused on minimizing the number of sites necessary to cover each species
one or more times. A solution to this problem is usually one from among a large number of alternative optimal configurations
of sites. This paper develops an iterative method for building reserve networks that produces an optimal solution to the species
set covering problem (SSCP) and also maximizes the number of species covered two or more times, three or more times, and so
on, conditional on the solution to the previous iteration. We refer to this as representational success. Thus, a pareto optimal species set covering is achieved that is preferable to an arbitrary optimal solution to the SSCP. 相似文献
308.
基于中德合作项目LILAC(生命景观中国),纳板河国家级自然保护区保护局与德国斯图加特大学及上海同济大学合作并于2010年3月和7月开展了两次水资源管理和保护的调研工作——“土地利用和水”子项目.项目的目的是研究保护区内种植橡胶及经济作物对水资源的影响。本文通过此次调研获得的数据,对纳板河水资源质量进行了初步评价。 相似文献
309.
310.
根据纳板河保护区的生物多样性和保护管理现状,提出了加强保护区生物多样性保护和促进保护区发展的对策。 相似文献