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1.
The law governing large carnivores in the western U.S. and western Canada abounds in jurisdictional complexity. In the U.S., different federal and state laws govern large carnivore conservation efforts; species listed under the Endangered Species Act are generally protected, whereas those subject to state regulation can be hunted, trapped, or otherwise taken. Neither federal nor state environmental or land management laws specifically protect large carnivores, though these laws can be used to protect habitat. A similar situation prevails in Canada. Canadian federal law does not address large carnivore conservation, although the national parks provide some secure habitat. Provincial laws vary widely; none of these laws specifically protect large carnivores, but some provisions can be invoked to protect habitat. Although the two nations have not entered any bilateral treaties to protect large carnivores, several species receive limited protection under multilateral treaty obligations. Despite these jurisdictional complexities, the existing legal framework can be built upon to promote large carnivore conservation efforts, primarily through a legally protected reserve system. Whether the political will exists to utilize fully the available legal authorities remains to be seen.  相似文献   

2.
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   

3.
Making Sense of the Policy Process for Carnivore Conservation   总被引:2,自引:0,他引:2  
Grizzly bears ( Ursus arctos horribilis ), mountain lions ( Puma concolor ), wolverines ( Gulo gulo ), wolves ( Canis lupus ), and lynx ( Felis lynx ) are all top-level carnivores in the Rocky Mountains of the northern U.S. and southern Canada. Because of their body size and high trophic position, these species require abundant prey species and large habitat areas—requirements that make their conservation a controversial public policy problem. Because the challenge of conserving these species extends beyond biological issues, it is necessary to involve other relevant disciplines and perspectives in understanding and solving the problem. Our examination of the context, content, and process of large carnivore conservation policies suggests more effective and active roles for scientists in designing solutions to the problem of landscape-level carnivore conservation. Scientists must develop an understanding of the range of participants in the policy process and the ways in which these participants receive and utilize information. This knowledge of the policy process could help scientists to better understand their roles in framing and clarifying policy questions, projecting the consequences of various alternatives, and presenting policy information in appropriate fora.  相似文献   

4.
美国的环保政策及对环保产业发展的影响   总被引:1,自引:0,他引:1  
美国的环保政策是一种经济发展政策 ,强调在提高美国工业竞争力和维护社会经济繁荣的基础上加强环境保护 ,强调通过环保技术的开发和应用实现具体的环保目标 ;措施上它强调灵活性、创新性、多样性和公众的自觉参与 ,创造了环保产业宽松和不断创新的环境。  相似文献   

5.
Recovery of gray wolf ( Canis lupus ) populations in North America depends on minimizing human-caused mortality and enhancing migration from stable source populations to suitable habitat unoccupied by wolves. We used a combination of field observation and DNA microsatellite genotyping to examine natural wolf colonization of Glacier National Park, Montana, and surrounding lands. We found high genetic variation in the colonizing population, showing that these packs were founded by multiple, unrelated wolves from Canada. High dispersal rates, long dispersal distances, and lack of a founding population bottleneck indicate that wolves in the United States and Canada should be viewed and managed as a single population. Restoration in the United States by artificial transplants from Alberta to Yellowstone National Park and central Idaho began in 1995. The transplanted wolves will likely aid demographic recovery, but permanently retaining the high genetic variation of wolves in the United States will require assuring gene flow throughout the central Rocky Mountains.  相似文献   

6.
Optimal foraging theory assumes that a forager can adequately assess the quality of its prey and predicts that parents feed their young low-quality foods only when suffering unpredicted reductions in their ability to provision. Wildland Florida scrub-jays feed their young exclusively arthropods, but suburban parents include human-provided foods in the nestling diet, with possible costs in terms of reduced growth and survival. We tested experimentally whether parents feed human-provided foods, given the apparent costs, because: 1) they do not discriminate between food types, 2) they switch to low-quality, abundant foods when natural food availability in the environment is low, or 3) they switch when the time needed to obtain natural food is high. Parents discriminated between natural and human-provided foods by showing a preference for natural foods when rearing young. When the handling time of natural foods was increased experimentally, parents in the suburban and wildland habitats switched to human-provided foods. Supplementation with natural foods increased preference for this food in both habitats. Suburban parents chose more natural foods than wildland parents, suggesting that they have a greater preference for natural foods. Regardless of preferences demonstrated at feeders, parents in both the suburbs and wildlands delivered mostly natural foods to nestlings, independent of natural food availability. Nonetheless, natural foods are likely to be scarcer in the environment than in our experimental tests. Because natural food availability is lower in the suburbs than in the wildland habitat, parents in the suburbs may be forced to switch to human-provided foods when feeding nestlings.  相似文献   

7.
The Role of Incentive Programs in Conserving the Snow Leopard   总被引:10,自引:0,他引:10  
Abstract:   Pastoralists and their livestock share much of the habitat of the snow leopard ( Uncia uncia ) across south and central Asia. The levels of livestock predation by the snow leopard and other carnivores are high, and retaliatory killing by the herders is a direct threat to carnivore populations. Depletion of wild prey by poaching and competition from livestock also poses an indirect threat to the region's carnivores. Conservationists working in these underdeveloped areas that face serious economic damage from livestock losses have turned to incentive programs to motivate local communities to protect carnivores. We describe a pilot incentive program in India that aims to offset losses due to livestock predation and to enhance wild prey density by creating livestock-free areas on common land. We also describe how income generation from handicrafts in Mongolia is helping curtail poaching and retaliatory killing of snow leopards. However, initiatives to offset the costs of living with carnivores and to make conservation beneficial to affected people have thus far been small, isolated, and heavily subsidized. Making these initiatives more comprehensive, expanding their coverage, and internalizing their costs are future challenges for the conservation of large carnivores such as the snow leopard.  相似文献   

8.
Roads, Development, and Conservation in the Congo Basin   总被引:16,自引:0,他引:16  
Abstract: Road density is closely linked to market accessibility, economic growth, natural resource exploitation, habitat fragmentation, deforestation, and the disappearance of wildlands and wildlife. Research in the Republic of Congo shows that roads established and maintained by logging concessions intensify bushmeat hunting by providing hunters greater access to relatively unexploited populations of forest wildlife and by lowering hunters' costs to transport bushmeat to market. Reconciling the contrary effects of roads on economic development and biodiversity conservation is one of the key challenges to wildlife managers in all nations. As the Democratic Republic of Congo prepares to reconstruct its almost completely collapsed road system, the government, donors, and conservation organizations have a unique opportunity to strategically prioritize investment in segments of the network that would maximize local and national economic benefits while minimizing adverse effects on forest wildlife.  相似文献   

9.
本文分析了江苏省角直镇乡镇经济腾飞与环境保护协调同步的发展过程,总结出了“统一规划、合理布局、集中控制、全面管理、环境保护与经济建设协调发展”的“角直模式”,并就模式的优缺点作了一定程度的探讨.  相似文献   

10.
Gray wolf (Canis lupus) recovery in the Rocky Mountains of the U.S. is proceeding by both natural recolonization and managed reintroduction. We used DNA microsatellite analysis of wolves transplanted from Canada to two reintroduction sites in the U.S. to study population structure in native and reintroduced wolf populations. Gene flow due to migration between regions in Canada is substantial, and all three recovery populations in the U.S. had high genetic variation. The reintroduced founders were moderately genetically divergent from the naturally colonizing U.S. population. These findings corroborate that the reintroduction more than meets generally accepted genetic guidelines. Maintaining this variation, however, will depend on ample reproduction in the first few generations. In the long term genetic variation will best be retained if migration occurs among the recolonizing and the two transplanted populations. Evidence from field observation and genetic studies shows extensive dispersal by wolves, and we conclude that exchange among these groups due to natural dispersal is likely if public tolerance and legal protection are adequate outside lands designated for wolf recovery.  相似文献   

11.
Hamann A  Wang T 《Ecology》2006,87(11):2773-2786
A new ecosystem-based climate envelope modeling approach was applied to assess potential climate change impacts on forest communities and tree species. Four orthogonal canonical discriminant functions were used to describe the realized climate space for British Columbia's ecosystems and to model portions of the realized niche space for tree species under current and predicted future climates. This conceptually simple model is capable of predicting species ranges at high spatial resolutions far beyond the study area, including outlying populations and southern range limits for many species. We analyzed how the realized climate space of current ecosystems changes in extent, elevation, and spatial distribution under climate change scenarios and evaluated the implications for potential tree species habitat. Tree species with their northern range limit in British Columbia gain potential habitat at a pace of at least 100 km per decade, common hardwoods appear to be generally unaffected by climate change, and some of the most important conifer species in British Columbia are expected to lose a large portion of their suitable habitat. The extent of spatial redistribution of realized climate space for ecosystems is considerable, with currently important sub-boreal and montane climate regions rapidly disappearing. Local predictions of changes to tree species frequencies were generated as a basis for systematic surveys of biological response to climate change.  相似文献   

12.
Ecological Sustainability as a Conservation Concept   总被引:3,自引:0,他引:3  
Neither the classic resource management concept of maximum sustainable yield nor the concept of sustainable development are useful to contemporary, nonanthropocentric, ecologically informed conservation biology. As an alternative, we advance an ecological definition of sustainability that is in better accord with biological conservation: meeting human needs without compromising the health of ecosystems. In addition to familiar benefit-cost constraints on human economic activity, we urge adding ecologic constraints. Projects are not choice-worthy if they compromise the health of the ecosystems in which human economic systems are embedded. Sustainability, so defined, is proffered as an approach to conservation that would complement wildlands preservation for ecological integrity, not substitute for wildlands preservation.  相似文献   

13.
从实现新时期统筹发展的国家战略需求出发,剖析了大都市群跨区域交叉污染、复合污染、累计污染的特点,指出这些区域已成为环境资源“漏斗区”和突发性环境危机的风险区。认为只有采取主动引导发展的国家环境战略才能有效地解决大都市群和环境的协调可持续发展问题。阐述了主动环保战略的重大措施包括引导调整发展布局、转变经济增长方式、转变生活方式、创新国家环境管理体制、创新环境科技体系和系统、人工提高环境承载能力等。  相似文献   

14.
近年来,经济发展与环境污染之间的关系成了社会经济发展的热点问题。本研究选取东莞市1990-2010年经济与环境数据,探究环境库兹涅茨曲线演替轨迹,得出研究时段内东莞市环境库兹涅茨曲线大体呈“倒U型”特征,其中“倒U型”峰值大约出现在2007年人均GDP为4.51万元时;工业废水、工业废气以及工业废渣排放量3项指标的环境库兹涅茨曲线,分别呈现弱的“倒U型”、“倒U型上升阶段”、“倒U型+倒U型上升阶段”特征。结果表明,东莞市环境库兹涅茨曲线特征与污染物排放量、产业结构、环保政策及投资等有较为密切的关系。结论建议:东莞市可以通过调整产业结构、加大环境保护投资力度等措施促进经济转型,加速“倒U型”曲线后半段的形成。  相似文献   

15.
The literature on trade openness, economic development, and the environment is largely inconclusive about the environmental consequences of trade. This study treats trade and income as endogenous and estimates the overall impact of trade openness on environmental quality using the instrumental variables technique. We find that whether or not trade has a beneficial effect on the environment varies depending on the pollutant and the country. Trade is found to benefit the environment in OECD countries. It has detrimental effects, however, on sulfur dioxide (SO2) and carbon dioxide (CO2) emissions in non-OECD countries, although it does lower biochemical oxygen demand (BOD) emissions in these countries. We also find the impact is large in the long term, after the dynamic adjustment process, although it is small in the short term.  相似文献   

16.
Abstract: Although many roadless areas on federal lands have been mapped in the United States since the 1970s, there has been little specific research on how and to what degree roadless areas contribute to biodiversity conservation. We examined the ecological attributes of mapped roadless areas for the Klamath-Siskiyou ecoregion of northwestern California and southwestern Oregon (U.S.A.). Attributes examined include special elements (such as natural heritage, serpentine geology, late-seral forests, Port Orford cedar [ Chamaecyparis lawsoniana ] ), and key watersheds; elevation and habitat representation; and overall landscape connectivity. We compared designated wilderness to roadless areas, giving special attention to the relative importance of small roadless areas (405–2024 ha). We mapped nearly 500 roadless areas of ≥405 ha. Roadless areas occupied more than twice the land area of wilderness (approximately 27% of the entire ecoregion) and contained approximately 36% of the known occurrences of heritage elements, 37% of the mapped serpentine habitats, 36% of the remaining late-seral forests, 60% of Port Orford cedar strongholds, and 42% of key watersheds for aquatic biodiversity. In addition, roadless areas were composed of significant amounts of low- and mid-elevation sites and a substantial number of the 214 mapped physical-biological habitat types with strong complementarity with designated wilderness. Fragmentation analyses showed that roadless areas contributed to regional connectivity in important ways. Also, small roadless areas were an important component of the roadless-areas conservation assessment. For the Klamath-Siskiyou ecoregion, roadless areas and designated wilderness provide an important foundation upon which to develop a comprehensive regional conservation strategy.  相似文献   

17.
The literature on trade openness, economic development, and the environment is largely inconclusive about the environmental consequences of trade. This study treats trade and income as endogenous and estimates the overall impact of trade openness on environmental quality using the instrumental variables technique. We find that whether or not trade has a beneficial effect on the environment varies depending on the pollutant and the country. Trade is found to benefit the environment in OECD countries. It has detrimental effects, however, on sulfur dioxide (SO2) and carbon dioxide (CO2) emissions in non-OECD countries, although it does lower biochemical oxygen demand (BOD) emissions in these countries. We also find the impact is large in the long term, after the dynamic adjustment process, although it is small in the short term.  相似文献   

18.
山地垂直带谱研究评述   总被引:1,自引:0,他引:1  
孙建  程根伟 《生态环境》2014,(9):1544-1550
山地垂直带谱研究是地学地域分异规律研究的重要内容之一,垂直带谱受土壤、气候和生物条件的影响,呈现不同的分布特征.在气候变化的影响下,垂直带谱也发生着剧烈的变化,并对气候变化起指示作用.本文通过梳理山地垂直带谱研究的主要历程,就山地垂直带谱的成因和格局以及研究方法的革新进行了探讨,并对我国的山地垂直带谱研究以及落基山脉和阿尔卑斯山脉等其他地域的研究状况进行综合论述.分析认为利用现有的观测数据,如气象、生物、土壤和地形等方面资料,研究山地垂直带谱的演替过程以及格局变化,关注未来气候变化情景下垂直带谱对于生态安全和环境保护显得尤为重要.同时,多学科的介入和交叉知识的融合对山地垂直带谱研究有着重要的意义,如研究带谱的形成,需要对地质构造、气象成因、植物生理、土壤生态等各方面的知识,在大尺度的研究中,遥感技术以及计算机信息工程要纳入其中.目前山地垂直带谱的理论基础也无法满足科学研究的需求,理论化研究需要进一步推进.综述期望为我国山地科学研究、综合地域分异、地理区划和环境变化研究提供-定的参考.  相似文献   

19.
森林旅游开发中环境保护问题的博弈分析   总被引:5,自引:0,他引:5  
介绍了博弈论的基本内容,运用了博弈论的基本原理分析和认识森林旅游开发和周边地区生态环境保护之间存在的矛盾,阐述了博弈论的基本理论在森林旅游开发环保中的应用,分析指出应结合市场机制和政府政策改变博弈方的收益,使博弈达到有利于环境保护的纳什均衡,提高森林旅游开发中的环境保护效率,以及处理森林旅游开发中环境保护问题的有效决策.  相似文献   

20.
Urban and exurban expansion results in habitat and biodiversity loss globally. We hypothesize that a coupled-model approach could connect urban planning for future cities with landscape ecology to consider wildland habitat connectivity. Our work combines urban growth simulations with models of wildlife corridors to examine how species will be impacted by development to test this hypothesis. We leverage a land use change model (SLEUTH) with structural and functional landscape-connectivity modeling techniques to ascertain the spatial extent and locations of connectivity related threats to a national park in southern Arizona, USA, and describe how protected areas might be impacted by urban expansion. Results of projected growth significantly altered structural connectivity (80%) when compared to current (baseline) corridor conditions. Moreover, projected growth impacted functional connectivity differently amongst species, indicating resilience of some species and near-complete displacement of others. We propose that implementing a geospatial-design-based model will allow for a better understanding of the impacts management decisions have on wildlife populations. The application provides the potential to understand both human and environmental impacts of land-system dynamics, critical for long-term sustainability.  相似文献   

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