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621.
Human–wildlife conflict is a major conservation challenge, and compensation for wildlife damage is a widely used economic tool to mitigate this conflict. The effectiveness of this management tool is widely debated. The relative importance of factors associated with compensation success is unclear, and little is known about global geographic or taxonomic differences in the application of compensation programs. We reviewed research on wildlife‐damage compensation to determine geographic and taxonomic gaps, analyze patterns of positive and negative comments related to compensation, and assess the relative magnitude of global compensation payments. We analyzed 288 publications referencing wildlife compensation and identified 138 unique compensation programs. These publications reported US$222 million (adjusted for inflation) spent on compensation in 50 countries since 1980. Europeans published the most articles, and compensation funding was highest in Europe, where depredation by wolves and bears was the most frequently compensated damage. Authors of the publications we reviewed made twice as many negative comments as positive comments about compensation. Three‐quarters of the negative comments related to program administration. Conversely, three‐quarters of the positive comments related to program outcomes. The 3 most common suggestions to improve compensation programs included requiring claimants to employ damage‐prevention practices, such as improving livestock husbandry or fencing of crops to receive compensation (n = 25, 15%); modifying ex post compensation schemes to some form of outcome‐based performance payment (n = 21, 12%); and altering programs to make compensation payments more quickly (n = 14, 8%). We suggest that further understanding of the strengths and weaknesses of compensation as a conflict‐mitigation tool will require more systematic evaluation of the factors driving these opinions and that differentiating process and outcomes and understanding linkages between them will result in more fruitful analyses and ultimately more effective conflict mitigation.  相似文献   
622.
Ongoing, rapid urban growth accompanied by habitat fragmentation and loss challenges biodiversity conservation and leads to decreases in ecosystem services. Application of the concept of ecological networks in the preservation and restoration of connections among isolated patches of natural areas is a powerful conservation strategy. However, previous approaches often failed to objectively consider the impacts of complex 3-D city environments on ecological niches. We used airborne lidar-derived information on the 3-D structure of the built environment and vegetation and detailed land use and cover data to characterize habitat quality, niche diversity, and human disturbance and to predict habitat connectivity among 38 identified habitat core areas (HCAs) in Nanjing, China. We used circuit theory and Linkage Mapper to create a landscape resistance layer, simulate habitat connectivity, and identify and prioritize important corridors. We mapped 64 links by using current flow centrality to evaluate each HCA's contribution and the links that facilitate intact connectivity. Values were highest for HCA links located in the west, south, and northeast of the study area, where natural forests with complex 3-D structures predominate. Two smaller HCA areas had high centrality scores relative to their extents, which means they could act as important stepping stones in connectivity planning. The mapped pinch-point regions had narrow and fragile links among the HCAs, suggesting they require special protection. The barriers with the highest impact scores were mainly located at the HCA connections to Purple Mountain and, based on these high scores, are more likely to indicate important locations that can be restored to improve potential connections. Our novel framework allowed us to sufficiently convey spatially explicit information to identify targets for habitat restoration and potential pathways for species movement and dispersal. Such information is critical for assessing existing or potential habitats and corridors and developing strategic plans to balance habitat conservation and other land uses based on scientifically informed connectivity planning and implementation.  相似文献   
623.
特许物权是自然资源用益物权。特许物权变动是指特许物权的设立、变更和终止行为。自然资源的稀缺性特征是为其变动过程被政府管制的重要原因,我国法律即采取特许物权变动行政许可制度,是国家为减少自然资源开发中的外部性问题而对私人权益实施的强制性干预。特许物权变动行政许可制度弱化特许物权人的最大化收益,产生了价格不菲的经济租。部分特许物权人为了谋求自身利益的最大化,会做出各种努力旨在影响特许物权变动中行政许可的向度与强度。一旦寻租行为得逞,自然资源的法定变动路径将备受扭曲,社会总体福利下降。寻租行为在特许物权变动中的发生类型呈现出独占型寻租和竞争型寻租两种,但其有着共同的衍生路径。追踪寻租行为的发生脉路,可以洞察到自然资源特许物权变动中寻租衍生的特殊动因。可以通过合理化特许物权结构、规范特许物权变动秩序和强化行政许可权力制衡力度等措施来对寻租的动因加以有效抑制。  相似文献   
624.
Assisted colonization of vascular plants is considered by many ecologists an important tool to preserve biodiversity threatened by climate change. I argue that assisted colonization may have negative consequences in arctic‐alpine and boreal regions. The observed slow movement of plants toward the north has been an argument for assisted colonization. However, these range shifts may be slow because for many plants microclimatic warming (ignored by advocates of assisted colonization) has been smaller than macroclimatic warming. Arctic‐alpine and boreal plants may have limited possibilities to disperse farther north or to higher elevations. I suggest that arctic‐alpine species are more likely to be driven to extinction because of competitive exclusion by southern species than by increasing temperatures. If so, the future existence of arctic‐alpine and boreal flora may depend on delaying or preventing the migration of plants toward the north to allow northern species to evolve to survive in a warmer climate. In the arctic‐alpine region, preventing the dispersal of trees and shrubs may be the most important method to mitigate the negative effects of climate change. The purported conservation benefits of assisted colonization should not be used to promote the migration of invasive species by forestry.  相似文献   
625.
Drawing on the idea that biodiversity is simply the diversity of living things, and that everyone knows what diversity and living things mean, most conservation professionals eschew the need to explain the many complex ways in which biodiversity is understood in science. On many biodiversity‐related issues, this lack of clarity leads to a communication gap between science and the general public, including decision makers who must design and implement biodiversity policies. Closing this communication gap is pivotal to the ability of science to inform sound environmental decision making. To address this communication gap, we propose a surrogate of biodiversity for communication purposes that captures the scientific definition of biodiversity yet can be understood by nonscientists; that is, biodiversity as a learning experience. The prerequisites of this or any other biodiversity communication surrogate are that it should have transdisciplinary relevance; not be measurable; be accessible to a wide audience; be usable to translate biodiversity issues; and understandably encompass biodiversity concepts. Biodiversity as a learning experience satisfies these prerequisites and is philosophically robust. More importantly, it can effectively contribute to closing the communication gap between biodiversity science and society at large. Experimentando la Biodiversidad como un Puente sobre el Vacío entre la Comunicación Ciencia‐Sociedad  相似文献   
626.
The taxonomic uniqueness of island populations is often uncertain which hinders effective prioritization for conservation. The Christmas Island shrew (Crocidura attenuata trichura) is the only member of the highly speciose eutherian family Soricidae recorded from Australia. It is currently classified as a subspecies of the Asian gray or long‐tailed shrew (C. attenuata), although it was originally described as a subspecies of the southeast Asian white‐toothed shrew (C. fuliginosa). The Christmas Island shrew is currently listed as endangered and has not been recorded in the wild since 1984–1985, when 2 specimens were collected after an 80‐year absence. We aimed to obtain DNA sequence data for cytochrome b (cytb) from Christmas Island shrew museum specimens to determine their taxonomic affinities and to confirm the identity of the 1980s specimens. The Cytb sequences from 5, 1898 specimens and a 1985 specimen were identical. In addition, the Christmas Island shrew cytb sequence was divergent at the species level from all available Crocidura cytb sequences. Rather than a population of a widespread species, current evidence suggests the Christmas Island shrew is a critically endangered endemic species, C. trichura, and a high priority for conservation. As the decisions typically required to save declining species can be delayed or deferred if the taxonomic status of the population in question is uncertain, it is hoped that the history of the Christmas Island shrew will encourage the clarification of taxonomy to be seen as an important first step in initiating informed and effective conservation action.  相似文献   
627.
Large‐scale infrastructure projects commonly have large effects on the environment. The planned construction of the Nicaragua Canal will irreversibly alter the aquatic environment of Nicaragua in many ways. Two distinct drainage basins (San Juan and Punta Gorda) will be connected and numerous ecosystems will be altered. Considering the project's far‐reaching environmental effects, too few studies on biodiversity have been performed to date. This limits provision of robust environmental impact assessments. We explored the geographic distribution of taxonomic and genetic diversity of freshwater fish species (Poecilia spp., Amatitlania siquia, Hypsophrys nematopus, Brycon guatemalensis, and Roeboides bouchellei) across the Nicaragua Canal zone. We collected population samples in affected areas (San Juan, Punta Gorda, and Escondido drainage basins), investigated species composition of 2 drainage basins and performed genetic analyses (genetic diversity, analysis of molecular variance) based on mitochondrial cytb. Freshwater fish faunas differed substantially between drainage basins (Jaccard similarity = 0.33). Most populations from distinct drainage basins were genetically differentiated. Removing the geographic barrier between these basins will promote biotic homogenization and the loss of unique genetic diversity. We found species in areas where they were not known to exist, including an undescribed, highly distinct clade of live bearing fish (Poecilia). Our results indicate that the Nicaragua Canal likely will have strong impacts on Nicaragua's freshwater biodiversity. However, knowledge about the extent of these impacts is lacking, which highlights the need for more thorough investigations before the environment is altered irreversibly.  相似文献   
628.
镧铈金属是制造稀土贮氢粉基体的优质原料,其应用的最大领域是制造电动车的高功率二次电池。针对目前世界石油紧缺,油价攀升及环境污染严重等问题,大力开发节能环保的电动车已成为当前世界交通能源转型的关键课题。因此镧铈金属的生产势必成为今后节能工作的发展方向。本文叙述镧铈金属生产工艺流程及原理,分析污染物产生环节以及污染物特征,排放方式等,针对性的提出相应的治理措施,为今后同类型的建设项目提供借鉴。  相似文献   
629.
针对菏泽市水环境污染现状,探讨了菏泽市主要水环境问题,识别了水环境污染的主要污染源,提出了改善菏泽市水环境的对策和建议。从菏泽市未来发展的空间布局来看,不同地区水环境保护的重点应有所侧重:北部地区重点是资源开发和重化工业发展过程中的水环境保护,南部地区重点是农业发展过程中的水环境保护,中部地区主要是生活污水的防治。  相似文献   
630.
介绍了英国负责海洋保护的主要管理机构,研究了英国海洋保护的相关法律与政策,分析了英国关于建立公海保护区的立场。从我国利益角度出发,对设立公海保护区所产生的利弊进行了分析。  相似文献   
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