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321.
Scholars observe an increased involvement of citizens in green space governance. This paper focuses on green self-governance, in which citizens play a major role in realizing, protecting and/or managing green space. While existing research on green self-governance focuses mostly on specific cases, we aim to contribute towards a large overview via an inventory of 264 green self-governance practices across The Netherlands. With this, we discuss the relevance of green self-governance for nature conservation and its relationship with authorities. In our analysis, we show that green self-governance practices are very diverse: they pursue a wide variety of physical and social objectives; employ a multitude of physical and political activities; involve different actors besides citizens; mobilize different internal and external funding sources; and are active within and outside of protected areas. While green self-governance can contribute towards protection and management of green space and towards social values, we highlight that this contribution is mostly of a local relevance. Most practices are small scale and objectives do not always match those of authorities. Although we speak of self-governance, authorities play an important role in many practices, for example, as financial donor, landowner or regulatory authority. In this, self-governance is often not completely ‘self’.

Abbreviations: PAA: Policy Arrangement Approach; NNN: National Nature Network; N2000: Natura 2000; NCOs: Nature Conservation Organizations; NGOs: Non-governmental organizations  相似文献   

322.
Establishing protected areas (PAs) is an essential strategy to reduce biodiversity loss. However, many PAs do not provide adequate protection due to poor funding, inadequate staffing and equipment, and ineffective management. As part of China's recent economic growth, the Chinese government has significantly increased investment in nature reserves over the past 20 years, providing a unique opportunity to evaluate whether PAs can protect threatened species effectively. We compiled data from published literature on populations of gibbons (Hylobatidae), a threatened taxon with cultural significance, that occurred in Chinese reserves after 1980. We evaluated the ability of these PAs to maintain gibbon habitat and populations by comparing forest cover and human disturbance between reserves and their surrounding areas and modeling the impact of reserve characteristics on gibbon population trends. We also assessed the perspective of reserve staff concerning PA management effectiveness through an online survey. Reserves effectively protected gibbon habitat by reducing forest loss and human disturbance; however, half the reserves lost their gibbon populations since being established. Gibbons were more likely to survive in reserves established more recently, at higher elevation, with less forest loss and lower human impact, and that have been relatively well studied. A larger initial population size in the 1980s was positively associated with gibbon persistence. Although staff of all reserves reported increased investment and improved management over the past 20–30 years, no relationship was found between management effectiveness and gibbon population trends. We suggest early and emphatic intervention is critical to stop population decline and prevent extinction.  相似文献   
323.
人与自然和谐是构建和谐社会的物质基础   总被引:13,自引:0,他引:13  
在剖析和谐社会及人与自然和谐基本内涵的基础上。通过分析资源短缺、生态破坏和环境污染对社会和谐的破坏作用。阐明了人与自然和谐是构建和谐社会的基本前提;通过分析加强环境保护、合理开发利用资源可以促进民主法治和公平正义。促使社会充满活力、安定有序。促进经济繁荣和持续发展。阐明了以人与自然和谐推进和谐社会的构建。进而全面论述了人与自然和谐是构建和谐社会的物质基础。  相似文献   
324.
The importance of large reserves has been long maintained in the scientific literature, often leading to dismissal of the conservation potential of small reserves. However, over half the global protected-area inventory is composed of protected areas that are <100 ha, and the median size of added protected area is decreasing. Studies of the conservation value of small reserves and fragments of natural area are relatively uncommon in the literature. We reviewed SCOPUS and WOK for studies on small reserve and fragment contributions to biodiversity conservation and ecosystem services, and fifty-eight taxon-specific studies were included in the review. Small reserves harbored substantial portions (upward of 50%) of regional species diversity for many taxa (birds, plants, amphibians, and small mammals) and even some endemic, specialist bird species. Unfortunately, small reserves and fragments almost always harbored more generalist and exotic species than large reserves. Community composition depended on habitat quality, surrounding land use (agricultural vs. urban), and reserve and fragment size, which presents opportunities for management and improvement. Small reserves also provided ecosystem services, such as pollination and biological pest control, and cultural services, such as recreation and improved human health. Limitations associated with small reserves, such as extinction debt and support of area-sensitive species, necessitate a complement of larger reserves. However, we argue that small reserves can make viable and significant contributions to conservation goals directly as habitat and indirectly by increasing landscape connectivity and quality to the benefit of large reserves. To effectively conserve biodiversity for future generations in landscapes fragmented by human development, small reserves and fragments must be included in conservation planning.  相似文献   
325.
The Thar Desert of North-west India has sprung into prominence recently because of nuclear testing in 1998. It occupies about 3 million km2 of diverse habitat. Each of the various habitats and landforms in the desert supports distinctive plants. 682 plant species have been identified including 107 grasses. Plants are removed for fuel, fodder, fencing and other farming, domestic and commercial purposes. There are about 200 species of plants with recognised medicinal uses in the desert. The medicinal usefulness of others is yet to be established. Commiphora wightii, Withania somnifera and Urginia indica have high glycoside content and are valued for gums and used in ayurvedic medicines for enhancing mental retention and memory enhancement. Such plants are being indiscriminately exploited for fuelwood.  相似文献   
326.
揭示安全的本质和规律,确认安全、安全规律和安全定理的概念,指导人们从本质上超前有效预防事故发生,这不仅对安全的认识是一次理性飞跃,而且对如何预防事故发生和达到征服事故的目的也是一次重大突破。  相似文献   
327.
Ecological distance-based spatial capture–recapture models (SCR) are a promising approach for simultaneously estimating animal density and connectivity, both of which affect spatial population processes and ultimately species persistence. We explored how SCR models can be integrated into reserve-design frameworks that explicitly acknowledge both the spatial distribution of individuals and their space use resulting from landscape structure. We formulated the design of wildlife reserves as a budget-constrained optimization problem and conducted a simulation to explore 3 different SCR-informed optimization objectives that prioritized different conservation goals by maximizing the number of protected individuals, reserve connectivity, and density-weighted connectivity. We also studied the effect on our 3 objectives of enforcing that the space-use requirements of individuals be met by the reserve for individuals to be considered conserved (referred to as home-range constraints). Maximizing local population density resulted in fragmented reserves that would likely not aid long-term population persistence, and maximizing the connectivity objective yielded reserves that protected the fewest individuals. However, maximizing density-weighted connectivity or preemptively imposing home-range constraints on reserve design yielded reserves of largely spatially compact sets of parcels covering high-density areas in the landscape with high functional connectivity between them. Our results quantify the extent to which reserve design is constrained by individual home-range requirements and highlight that accounting for individual space use in the objective and constraints can help in the design of reserves that balance abundance and connectivity in a biologically relevant manner.  相似文献   
328.
The protection and sustainable management of habitat trees is an integral part of modern forest nature conservation concepts such as retention forestry. Bats, cavity-nesting birds, arboreal marsupials, and many different saproxylic species depend on habitat trees and their great variety of microhabitats and old-growth characteristics. With a focus on insights from temperate forests, we traced the development of habitat-tree protection over 200 years. The idea was first conceptualized by foresters and natural scientists in the early 19th century. At that time, utilitarian conservation aimed to protect cavity trees that provided roosts and nesting holes for insectivorous bats and birds. By the second half of the 19th century, habitat-tree protection was well known to foresters and was occasionally implemented. Knowledge of the protection of large old trees, a special kind of habitat tree, for sociocultural and aesthetic reasons developed similarly. But, many foresters of that time and in the following decades fundamentally rejected protection of habitat trees for economic reasons. Beginning in the 1970s, forest conservation and integrative forest management became increasingly important issues worldwide. Since then, the protection of habitat trees has been implemented on a large scale. Long-term views on the development of conservation concepts are important to inform the implementation of conservation today. In particular, historical analyses of conservation concepts allow the testing of long-term conservation outcomes and make it possible to study the resilience of conservation approaches to changing social or ecological conditions. We encourage all conservation ecologists to assess the practical and conceptual impact of the initial ideas that led to modern conservation concepts in terms of long-term biodiversity conservation.  相似文献   
329.
Over the past 5 decades, scientists have been documenting negative anthropogenic environmental change, expressing increasing alarm, and urging dramatic socioecological transformation in response. A host of international meetings have been held, but the erosion of biological diversity continues to accelerate. Why, then, has no effective political action been taken? We contend that part of the answer may lie in the anthropocentric ethical premises and moral rhetoric typically deployed in the cause of conservation. We further argue that it is essential to advance moral arguments for biodiversity conservation that are not just based on perceived human interests but on ecocentric values, namely, convictions that species and ecosystems have value and interests that should be respected regardless of whether they serve human needs and aspirations. A broader array of moral rationales for biodiversity conservation, we conclude, would be more likely to lead to effective plans, adopted and enforced by governments, designed to conserve biological diversity. A good place to start in this regard would be to explicitly incorporate ecocentric values into the recommendations that will be made at the conclusion of the 15th meeting of the parties to the Convention on Biological Diversity, scheduled to be held in October 2020.  相似文献   
330.
Abstract

As the protected areas of land and coastal environment, nature reserves are designed to address how to reconcile the conservation of biodiversity, the quest for economic and social development and the maintenance of cultural values. This paper establishes a framework for nature reserve development that seeks to incorporate ecotourism into its strategies. The overall purpose was to identify the information needs required for a comprehensive nature reserve that incorporates ecotourism related values. It also illustrates the utility of this framework in the context of the Wuzhishan Mountain Region of China. A literature review, the first phase of a visionary strategy and a subsequent gap analysis for available management information were undertaken in order to achieve this paper's purpose. Finally, recommendations are presented for integrating ecotourism into nature reserve development in the Wuzhishan Mountain Region.  相似文献   
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