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1.
Fire is an important disturbance agent in Myanmar impacting several ecosystems. In this study, we quantify the factors impacting vegetation fires in protected and non-protected areas of Myanmar. Satellite datasets in conjunction with biophysical and anthropogenic factors were used in a spatial framework to map the causative factors of fires. Specifically, we used the frequency ratio method to assess the contribution of each causative factor to overall fire susceptibility at a 1km scale. Results suggested the mean fire density in non-protected areas was two times higher than the protected areas. Fire-land cover partition analysis suggested dominant fire occurrences in the savannas (protected areas) and woody savannas (non-protected areas). The five major fire causative factors in protected areas in descending order include population density, land cover, tree cover percent, travel time from nearest city and temperature. In contrast, the causative factors in non-protected areas were population density, tree cover percent, travel time from nearest city, temperature and elevation. The fire susceptibility analysis showed distinct spatial patterns with central Myanmar as a hot spot of vegetation fires. Results from propensity score matching suggested that forests within protected areas have 11% less fires than non-protected areas. Overall, our results identify important causative factors of fire useful to address broad scale fire risk concerns at a landscape scale in Myanmar.  相似文献   

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Leon Bennun  Peter Njoroge 《Ostrich》2013,84(1-2):164-167
Bennun, L. & Njoroge, P. 2000. Important Bird Areas in Kenya. Ostrich 71 (1 & 2): 164–167.

The process of defining Important Bird Areas in Kenya has been underway since January 1995, with financial support from the Royal Society for the Protection of Birds. Literature review has proceeded in parallel with field surveys, which are still ongoing. Some 65 globally Important Bird Areas have so far been identified, and this total is likely to increase. Sites were intitially selected using the criteria of threatened species (37 sites) and congregatory species (15 sites). Additional sites were then identified for biome-restricted and restricted-range species, using information from the Bird Atlas of Kenya; these sites must form part of a regional set. Threatened species sites are concentrated in forests (on the coastal strip, in the central highlands and in western Kenya) and papyrus swamps. Congregatory-species sites are concentrated along the Rift Valley and the coast. The remaining sites are concentrated in semi-arid areas to the immediate north and east of the central plateau, and in highland forest on each side of the Rift Valley. No IBAs have yet been identified in the flat, arid north-eastern sector of the country. A large number of sites require additional protection and/or improved management. Particular priorities include several papyrus IBAs around Lake Victoria, among them Lake Kanyaboli and Yala and Sare Swamps, grassland pockets in Mungatsi and Nambale, Western Province; the Kakamega, South Nandi and North Nandi Forests; the increasingly fragmented coastal forests, including Arabuko-Sokoke Forest; and the Taita Hills. Information on the IBA process and its results is being distributed to decision-makers through a high-level IBA Advisory council, with encouraging intitial results.  相似文献   

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Protecting an endangered and highly poached species can conflict with providing an open and ecologically connected landscape for coexisting species. In Kenya, about half of the black rhino (Diceros bicornis) live in electrically fenced private conservancies. Purpose-built fence-gaps permit some landscape connectivity for elephant while restricting rhino from escaping. We monitored the usage patterns at these gaps by motion-triggered cameras and found high traffic volumes and predictable patterns of prey movement. The prey-trap hypothesis (PTH) proposes that predators exploit this predictable prey movement. We tested the PTH at two semi-porous reserves using two different methods: a spatial analysis and a temporal analysis. Using spatial analysis, we mapped the location of predation events with GPS and looked for concentration of kill sites near the gaps as well as conducting clustering and hot spot analysis to determine areas of statistically significant predation clustering. Using temporal analysis, we examined the time lapse between the passage of prey and predator and searched for evidence of active prey seeking and/or predator avoidance. We found no support for the PTH and conclude that the design of the fence-gaps is well suited to promoting connectivity in these types of conservancies.  相似文献   

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For the past several years, there has been growing interest in understanding the dynamics of parasites in ecosystems, as well as the diversity of ways in which they interfere with conservation and health preoccupations. Although it is widely recognized that many conservation practices (e.g., wildlife translocations, species removal, food supplementation) may be associated with parasite-related problems, less attention has been devoted to exploring the parasitological consequences of the overcrowding of animals in protected wildlife areas. Here, we discuss this important ecological/epidemiological problem, presenting at the same time an overview of the main questions and challenges in this field. Using empirical and theoretical examples chosen from the literature, we focus particularly on the interactions between the overcrowding of free living species and parasite population dynamics, the evolution of parasite virulence, the indirect effects on the structure of invertebrate communities, as well as the nutritional value of prey species. We argue that conservation policies should be aware more than ever of this problem, especially given the serious health risks currently posed by the spread of virulent viruses (e.g., avian influenza).  相似文献   

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加拿大及其保护区系统在国际自然保护界居领先地位。这个世界第三大保护区系统[3] 具有 4个主要的层次 :国家级、省 /地区级、区域级和地方级。其子系统也有跨两个以上层次的 ,还有的成为国际遗产组织的成员。本文拟对这一庞大而有序的保护区系统进行分析研究。1 国家系统加拿大的国家级自然保护区系统主要有 :由加拿大文化遗产部的加拿大公园局管理的国家公园和国家海洋保护区 ,由加拿大环境部的加拿大野生动植物保护局管理的国家候鸟禁猎区和国家野生动植物保护区 ,由国家首都委员会管理的国家首都保护地。这些系统形成加拿大国家级保护…  相似文献   

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This article is concerned with the implementation of community-based conservancies (CBC) in conflict-ridden pastoralist areas of northern Kenya and whether the creation of protected areas can facilitate the resolution of conflict. Evidence from ethnographic research in East Pokot, Kenya, reveals a mixed picture. In the last decade, three CBCs were established along the administrative borders. Two of them are located in contested areas between the Pokot and neighboring pastoralists. In order to ensure their long-term success in terms of wildlife conservation and economic viability they must act as catalysts for inter-ethnic conflict resolution. In one case, the implementation proved successful, while in the other it exacerbated tensions and led to ethnic violence. In addition, issues of conservation are also embedded in deeper intra-societal struggles over the reconfiguration and renegotiation of access to and control over land. Drawing on ethnographic data and recent literature this research sheds light on unexpected consequences of CBC.  相似文献   

8.

Background and Question

The harvesting of medicinal plants from wild sources is escalating in many parts of the world, compromising the long-term survival of natural populations of medicinally important plants and sustainability of sources of raw material to meet pharmaceutical industry needs. Although protected areas are considered to play a central role in conservation of plant genetic resources, the effectiveness of protected areas for maintaining medicinal plant populations subject to intense harvesting pressure remain largely unknown. We conducted genetic and demographic studies of Nothapodytes nimmoniana Graham, one of the extensively harvested medicinal plant species in the Western Ghats biodiversity hotspot, India to assess the effectiveness of protected areas in long-term maintenance of economically important plant species.

Methodology/Principal Findings

The analysis of adults and seedlings of N. nimmoniana in four protected and four non-protected areas using 7 nuclear microsatellite loci revealed that populations that are distributed within protected areas are subject to lower levels of harvesting and maintain higher genetic diversity (He = 0.816, Ho = 0.607, A = 18.857) than populations in adjoining non-protected areas (He = 0.781, Ho = 0.511, A = 15.571). Furthermore, seedlings in protected areas had significantly higher observed heterozygosity (Ho = 0.630) and private alleles as compared to seedlings in adjoining non-protected areas (Ho = 0.426). Most populations revealed signatures of recent genetic bottleneck. The prediction of long-term maintenance of genetic diversity using BOTTLESIM indicated that current population sizes of the species are not sufficient to maintain 90% of present genetic diversity for next 100 years.

Conclusions/Significance

Overall, these results highlight the need for establishing more protected areas encompassing a large number of adult plants in the Western Ghats to conserve genetic diversity of economically and medicinally important plant species.  相似文献   

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It is a globally important challenge to meet increasing demands for resources and, at the same time, protect biodiversity and ecosystem services. Farming is usually regarded as a major threat to biodiversity due to its expansion into natural areas. We compared biodiversity of bees and wasps between heterogeneous small-scale farming areas and protected forest in northern coastal Belize, Central America. Malaise traps operated for three months during the transition from wet to dry season. Farming areas consisted of a mosaic of mixed crop types, open habitat, secondary forest, and agroforestry. Mean species richness per site (alpha diversity), as well as spatial and temporal community variation (beta diversity) of bees and wasps were equal or higher in farming areas compared to protected forest. The higher species richness and community variation in farmland was due to additional species that did not occur in the forest, whereas most species trapped in forest were also found in farming areas. The overall regional species richness (gamma diversity) increased by 70% with the inclusion of farming areas. Our results suggest that small-scale farming systems adjacent to protected forest may not only conserve, but even favour, biodiversity of some taxonomic groups. We can, however, not exclude possible declines of bee and wasp diversity in more intensified farmland or in landscapes completely covered by heterogeneous farming systems.  相似文献   

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介绍了北京地区野牛动物救护工作的发展历程和现状,野生动物救护种类和伤病情况.根据在工作中遇到的实际情况,提出了野生动物救护中存在的问题和不足,并从野生动物管理和救护技术两个方面提出了相关建议和解决措施.  相似文献   

12.
The woodlands of the Masai Mara National Reserve in Kenya have suffered dramatic declines over four decades as a result of elephant and fire pressure. This study examined the current status of woody resources in the Reserve and browse pressure thereon, using both classification (TWINSPAN) and ordination (DCA) techniques. From 333 widespread regular plots used to survey the vegetation, a total of 62 woody species were identified. Thirteen woody habitats were identified on the basis of species composition, varying from species‐rich closed thickets and forest to less diverse open grasslands. A NW/SE stratification of the more open habitats was observed, possibly as a result of differences in soils, rainfall and drainage. Both plant density and diversity were lower than in communal and privately managed areas outside the Reserve. Moreover, browser pressure was substantially higher than that observed previously in the ecosystem, and suggests increased competition for scarcer woody resources within the Reserve. This has implications for the management of the ecosystem as a whole. As woodland and thickets continue to decline, long‐term monitoring should expand to encompass the wider habitat diversity of the open grasslands and unprotected areas where much of the regeneration potential resides.  相似文献   

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Transboundary marine protected areas have been proposed in East Africa to tackle threats to marine biodiversity, meet international MPA targets, promote tourism, and contribute to poverty reduction. This article examines what may drive, facilitate, or constrain states in creating a regime for transboundary MPAs. In East Africa, a regime between Mozambique and Tanzania is not yet formed and may be indefinitely delayed due to oil prospecting and exploration. There is, however, a well-developed regime between Mozambique and South Africa that has resulted in the two adjoining MPAs being declared the first transboundary MPA on the continent.  相似文献   

15.
Forest fragmentation and habitat loss are detrimental to top carnivores, such as jaguars (Panthera onca) and pumas (Puma concolor), but effects on mesocarnivores, such as ocelots (Leopardus pardalis), are less clear. Ocelots need native forests, but also might benefit from the local extirpation of larger cats such as pumas and jaguars through mesopredator release. We used a standardized camera trap protocol to assess ocelot populations in six protected areas of the Atlantic forest in southeastern Brazil where over 80% of forest remnants are < 50 ha. We tested whether variation in ocelot abundance could be explained by reserve size, forest cover, number of free-ranging domestic dogs and presence of top predators. Ocelot abundance was positively correlated with reserve size and the presence of top predators (jaguar and pumas) and negatively correlated with the number of dogs. We also found higher detection probabilities in less forested areas as compared to larger, intact forests. We suspect that smaller home ranges and higher movement rates in smaller, more degraded areas increased detection. Our data do not support the hypothesis of mesopredator release. Rather, our findings indicate that ocelots respond negatively to habitat loss, and thrive in large protected areas inhabited by top predators.  相似文献   

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Identifying Corridors among Large Protected Areas in the United States   总被引:1,自引:0,他引:1  
Conservation scientists emphasize the importance of maintaining a connected network of protected areas to prevent ecosystems and populations from becoming isolated, reduce the risk of extinction, and ultimately sustain biodiversity. Keeping protected areas connected in a network is increasingly recognized as a conservation priority in the current era of rapid climate change. Models that identify suitable linkages between core areas have been used to prioritize potentially important corridors for maintaining functional connectivity. Here, we identify the most “natural” (i.e., least human-modified) corridors between large protected areas in the contiguous Unites States. We aggregated results from multiple connectivity models to develop a composite map of corridors reflecting agreement of models run under different assumptions about how human modification of land may influence connectivity. To identify which land units are most important for sustaining structural connectivity, we used the composite map of corridors to evaluate connectivity priorities in two ways: (1) among land units outside of our pool of large core protected areas and (2) among units administratively protected as Inventoried Roadless (IRAs) or Wilderness Study Areas (WSAs). Corridor values varied substantially among classes of “unprotected” non-core land units, and land units of high connectivity value and priority represent diverse ownerships and existing levels of protections. We provide a ranking of IRAs and WSAs that should be prioritized for additional protection to maintain minimal human modification. Our results provide a coarse-scale assessment of connectivity priorities for maintaining a connected network of protected areas.  相似文献   

18.
When protected areas reduce threats within their boundaries, they often displace a portion of these threats into adjacent areas through a process known as ‘leakage’, undermining conservation objectives. Using theoretical models and a case study of terrestrial mammals in Indonesia, we develop the first theoretical explanation of how leakage impacts conservation actions, and highlight conservation strategies that mitigate these impacts. Although leakage is a socio-economic process, we demonstrate that its negative impacts are also affected by the distribution of species, with leakage having larger impacts in landscapes with homogeneous distribution of species richness. Moreover, leakage has a greater negative effect when conservation strategies are implemented opportunistically, even creating the potential for perversely negative consequences from protected area establishment. Leakage thereby increases the relative benefits of systematic conservation planning over opportunism, especially in areas with high leakage and heterogeneously distributed species. Although leakage has the potential to undermine conservation actions, conservation planning can minimize this risk.  相似文献   

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Abstract

World fish resources, fishing methods, and processing operations in the seafood industry are described. The fishery situation in developing countries (LDCs) is discussed, with particular reference to artisanal and other local fisheries, and examples are cited to illustrate the structure of the industry. Technology transfer from developed countries to LDCs is discussed and recommendations are presented for future technology transfer programs. It is concluded that an integrated complex of small projects with defined, attainable objectives and immediate impact on income and food supply of the LDC populations is likely to be more successful than large‐scale programs with little immediate payoff. A case study of fisheries in two developing countries, Thailand and Peru, and extensive tabulation of statistical data on catches, value of catch, and unit value of fish species groups for selected countries, with a discussion of the significance of the data, are presented in an appendix.  相似文献   

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Indigenous Protected Areas (IPAs) recognize that “country” constitutes land and waters that have enduring cultural, social, and economic linkages for Aboriginal and Torres Strait Islander peoples that extend over millennia, and which are critical to sustainable Indigenous futures. Within Australia's conservation system, IPAs become part of the National Reserve System (NRS) when Indigenous peoples voluntarily announce their intention to manage “country,” in accordance with their law, custom, and culture, and consistently with national and international conservation guidelines. The NRS requirement is that land is managed “in perpetuity” which highlights a potential tension between with the conservation goals and the voluntary character of IPAs. Ecological restoration in IPAs also raises contested ideas about what is “natural,” the relevant “baseline” for restoration, and what are the objectives to be achieved—ecological or cultural sustainability? Experience from Healthy Country Planning in IPAs indicates that restoration of traditional owner decision‐making, as well as respectful use and valuing community knowledge, is central to the sustainability of outcomes. Ecological restoration is most effectively achieved by restoring governance processes that support Indigenous peoples given the inseparability of cultural, social, economic, and ecological objectives.  相似文献   

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