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81.
An important element of resource management and conservation is an understanding of the tradeoffs between marketed products, such as timber, and measures of environmental quality, such as biodiversity. In this paper, we develop an integrated economic-ecological spatial optimization model that we then apply to evaluate alternate forest policies on a 560,000 km2 study region of managed boreal forest in Alberta and British Columbia, Canada. The integrated model incorporates dynamic forest sector harvesting, current levels of oil and gas sector development, coarse-filter or habitat-based old forest indicators, a set of empirical forest bird abundance models, and statistical models of the natural and current fire regimes. Using our integrated model, economic tradeoff curves, or production possibility frontiers, are developed to illustrate the cost of achieving coarse-filter targets by a set time (50 years) within a 100-year time horizon. We found levels of ecological indicators and economic returns from the timber industry could both be increased if spatial constraints imposed by the current policy environment were relaxed; other factors being equal, this implies current policy should be revised. We explore the production possibility frontier's relationship to the range of natural variation of old forest habitat, and show how this range can be used to guide choices of preferred locations along the frontier. We also show that coarse-filter constraints on the abundance of certain habitat elements are sufficient to satisfy some fine-filter objectives, expressed as the predicted abundances of various species of songbirds.  相似文献   
82.
This paper examines the Norwegian national authorities’ responses to combined use and protection planning for huge protected areas and their buffer zone in northern Norway. The processes were chaired by county delegates and included a wide range of stakeholders. In-depth semi-structured interviews, participatory observation and document analyses have been conducted to investigate the potential of these processes and response from national environmental authorities. The paper suggests that national environmental authorities partly ignored the potential strengths associated with combined use and protection plans and over-emphasised the potential environmental threats stemming from local management. Moreover, these trade-offs seemed to be guided on a rather vague scientific basis. In conclusion, the paper argues that central environmental administration needs to (i) engage actively in participatory processes, (ii) present clear rationales, if rejecting local initiatives, (iii) acknowledge the potential for man–nature relationships as beneficial for environmental assets, and (iv) relate interpretation of law to integrative policies.  相似文献   
83.
This study identified the changing preferences of country park visitors in Hong Kong and the potential for such changes to have further negative impacts on the ecologically sensitive areas of country parks. A questionnaire was used to collect feedback from 644 country park visitors to understand their preferences and visitation patterns. To investigate visitors’ preferences and behaviours and to develop better visitor management strategies, the survey data were compared with studies conducted 20 years ago. The results showed that the most popular nature‐based activities of 20 years ago, namely, picnicking and barbecuing, have significantly declined in popularity, while other activities, namely, nature studies and nature photography, have surged in popularity in recent years. These changes in visitor preferences have directly increased the negative impacts of visitors on country parks as they dispersed away from the high intensity recreation zones to the ecological sensitive areas. This emerging group of country park visitors has not been fully considered in the existing approach to visitor management and may irreversibly impact the ecological value of country parks. In this study, visitor management in Hong Kong's country parks was reviewed based on these research findings, and potential improvements were suggested.  相似文献   
84.
Nestmate recognition in ants is possible without tactile interaction   总被引:1,自引:0,他引:1  
Ants of the genus Camponotus are able to discriminate recognition cues of colony members (nestmates) from recognition cues of workers of a different colony (non-nestmates) from a distance of 1 cm. Free moving, individual Camponotus floridanus workers encountered differently treated dummies on a T-bar and their behavior was recorded. Aggressive behavior was scored as mandibular threat towards dummies. Dummies were treated with hexane extracts of postpharyngeal glands (PPGs) from nestmates or non-nestmates which contain long-chain hydrocarbons in ratios comparable to what is found on the cuticle. The cuticular hydrocarbon profile bears cues which are essential for nestmate recognition. Although workers were prevented from antennating the dummies, they showed significantly less aggressive behavior towards dummies treated with nestmate PPG extracts than towards dummies treated with non-nestmate PPG extracts. In an additional experiment, we show that cis-9-tricosene, an alkene naturally not found in C. floridanus' cuticular profile, is behaviorally active and can interfere with nestmate recognition when presented together with a nestmate PPG extract. Our study demonstrates for the first time that the complex multi-component recognition cues can be perceived and discriminated by ants at close range. We conclude that contact chemosensilla are not crucial for nestmate recognition since tactile interaction is not necessary.  相似文献   
85.
Canadian and US marine conservation law, and other related law, was analyzed to determine if it reflected ecological criteria needed to implement connectivity among marine protected areas of the northeast Pacific in the proposed trilateral Baja to Bering Sea (B2B) initiative. The analysis included both nations’ federal laws and those of California, Oregon, Washington, Alaska, and British Columbia. While legal provisions exist already to implement marine protected areas for varying reasons, there is little capacity in most laws to create connectivity among them for conservation purposes. Only California's legislation contained explicit provisions for all the criteria. Other federal, state, and provincial laws, while containing provisions for species at risk and vulnerable habitats, generally lacked explicit provisions for the vital criteria, size of area, migratory patterns, and recruitment patterns. Implementation, future management, and protection of the proposed B2B marine network would be facilitated by amendment of both Canadian and US laws. Some of the ecological criteria are already implied implicitly or vaguely, but they need to be made explicit in the amended law. The legislative model of California could serve as a template for amending the laws of other jurisdictions in the B2B venture.  相似文献   
86.
天目山国家级保护区加入世界生物圈保护区网络已经10年,为了更好地保护其生物多样性和文化多样性,并可持续地利用好该保护区的自然资源,需适应客观形势发展的要求,把天目山国家级保护区建成为名副其实的生物圈保护区。采用现场实地考察、社区居民访谈、保护区管理者和政府人员座谈、历史资料查询等方法,了解到天目山保护区在自然资源保护、科研监测、教育培训、资源持续利用和生态旅游等方面取得了不少的成绩,但也存在诸如保护区面积尚欠不够、毛竹林资源能否合理利用和柳杉林的衰亡与病虫害的防治等问题。按照生物圈保护区的管理理念并参照以上的调查和思考,提出下列3条建议:一是扩大保护区的面积,二是建立一个完善的保护区共管机制,三是建立学术顾问委员会协助推动保护区各方面的工作。  相似文献   
87.
针对煤矿瓦斯爆炸灾害子系统的复杂非线性动力学特性,以南方某省1958—2007年的煤矿瓦斯爆炸事故发生数构建时间序列,应用霍斯特时间序列数据的标度行为,提出瓦斯爆炸时间序列的重标极差分析(R/S分析)方法。结果表明:瓦斯爆炸时间序列的霍斯特指数为0.550 2,分形维数为1.449 8,其分式布朗运动轨迹表现出一定的持久性和非高斯性。为诊断瓦斯爆炸事故时间序列变异年份,对时间序列进行分段R/S分析,获得变异年份为1974年,以1974年为分界点构成2个时间序列,霍斯特指数分别为0.589 1和0.697 5,分形维数为1.410 9和1.302 5,与煤矿瓦斯爆炸事故时间序列的持久性趋势一致。煤矿瓦斯爆炸事故时间序列看似无序却蕴藏规律,反映了系统的动力学变化特征,R/S分析方法可以描述煤矿瓦斯爆炸事故时间序列的动力学特征。  相似文献   
88.
在国家公园体制改革背景下,“建立以国家公园为主体的自然保护地体系”对我国自然保护地优化整合提出了系列要求。福建省正在进行自然保护地优化整合,泰宁县是全省自然保护地交叉重叠最复杂的区域之一。以泰宁县为例,基于实地调研和专家意见,构建了三个优化整合的情景规划方案:(1)维持现状,不整合;(2)以泰宁国家地质公园为主体的整合;(3)以泰宁国家公园为主体的整合。基于对方案的成本效益比较,结果显示:方案3的存在和使用价值最高,成本持中;方案1的价值保护持中,成本最低;方案2价值最低,成本最高。研究为福建省县市尺度开展自然保护地优化整合提供思路和技术支持,亦为国内外自然保护地的边界优化提供参考。  相似文献   
89.
国外大尺度生态廊道保护进展与秦岭国家公园建设   总被引:1,自引:0,他引:1  
大型山脉在其走向上往往是生物扩散和分布的天然廊道。然而,由于人类干扰引起的生境碎片化,山地廊道的连通性已大为降低。20世纪以来,人们普遍意识到当前或过去的自然保护措施往往规模太小,无法维持许多物种的长期生存及其所依赖的生态过程。因而,山地廊道的连通性保护日益受到关注,大尺度生态廊道被认为是长远意义上保护气候变化下生物多样性的最优策略。综述连通性保护和生态廊道的概念、发展历程及国外大尺度生态廊道建设实践的经验,并从连通性保护的角度对秦岭国家公园建设提出一些建议,强调大尺度的连通性保护和生态廊道建设对于国家公园自然生态系统的长远保护具有重要意义。  相似文献   
90.
Conservation of biodiversity in managed forest landscapes needs to be complemented with new approaches given the threat from rapid climate change. Most frameworks for adaptation of biodiversity conservation to climate change include two major strategies. The first is the resistance strategy, which focuses on actions to increase the capacity of species and communities to resist change. The second is the transformation strategy and includes actions that ease the transformation of communities to a set of species that are well adapted to the novel environmental conditions. We suggest a number of concrete actions policy makers and managers can take. Under the resistance strategy, five tools are introduced, including: identifying and protecting forest climate refugia with cold-favored species; reducing the effects of drought by protecting the hydrological network; and actively removing competitors when they threaten cold-favored species. Under the transformation strategy, we suggest three tools, including: enhancing conditions for forest species favored by the new climate, but currently disfavored by forest management, by planting them at suitable sites outside their main range; and increasing connectivity across the landscape to enhance the expansion of warm-favored species to sites that have become suitable. Finally, we suggest applying a landscape perspective and simultaneously managing for both retreating and expanding species. The two different strategies (resistance and transformation) should be seen as complementary ways to maintain a rich biodiversity in future forest ecosystems.  相似文献   
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