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1.
The continuing alteration of global ecosystems has put a high premium on the development of a system of representative conservation reserves. In addition to existing national parks and reserves, and a developing international system of biosphere reserves, state and provincial parks can serve to strengthen the network of protected natural areas. An analysis of Texas state parks shows that they are a viable supplement to national park areas in the state. The level of resource protection within the parks is generally high, and they contribute to the representation of the state's eight natural regions and several subregions.  相似文献   

2.
We applied six measures of effectiveness to recent decisions about additional conservation areas in north-eastern New South Wales. Three have been widely used previously: (1) number of conservation areas; (2) total extent of conservation areas; and (3) representativeness (the proportion of natural features such as forest types or animal species represented in conservation areas to some targeted level). The other measures were: (4) efficiency or representation bias (the extent to which some features are protected above target levels at the expense of others that remain poorly protected); (5) relative protection of vulnerable areas within public land (percentage protection of flat, fertile areas relative to that of steep and/or infertile areas); and (6) relative protection of vulnerable areas across all tenures (the correlation between the amount of protection given to features and their vulnerabilities to clearing). We applied the measures in two chronological comparisons: the reserve system in 1994, 1996 and 1997; and before and after the Interim Assessment Process of 1996 which involved negotiations over new reserves and extensive unreserved areas that were temporarily deferred from logging. Over the study period, despite expansion of formal conservation and progress towards quantitative conservation targets, gazetted reserves remained strongly biased to the steep and/or infertile parts of public lands. Both gazetted reserves and areas deferred from logging increased the bias in protection away from forest types most vulnerable to clearing and for which regional conservation targets had already been most compromised. Two major challenges for future conservation decisions in the region are common to conservation planning generally: (1) to focus protection within public tenure on habitats and species most vulnerable to threatening processes such as logging; and (2) to provide more effective conservation management on private lands where loss of native vegetation continues.  相似文献   

3.
The transformation and degradation of tropical forest is thought to be the primary driving force in the loss of biodiversity worldwide. Developing countries are trying to counter act this massive lost of biodiversity by implementing national parks and biological reserves. Costa Rica is no exception to this rule. National development strategies in Costa Rica, since the early 1970s, have involved the creation of several National Parks and Biological Reserves. This has led to monitoring the integrity of and interactions between these protected areas. Key questions include: “Are these areas' boundaries respected?”; “Do they create a functioning network?”; and “Are they effective conservation tools?”. This paper quantifies deforestation and secondary growth trends within and around protected areas between 1960 and 1997. We find that inside of national parks and biological reserves, deforestation rates were negligible. For areas outside of National Parks and Biological reserves we report that for 1-km buffer zones around such protected areas, there is a net forest gain for the 1987/1997 time period. Thus, it appears that to this point the boundaries of protected areas are respected. However, in the 10-km buffer zones we find significant forest loss for all study periods. This suggests that increasing isolation of protected areas may prevent them from functioning as an effective network.  相似文献   

4.
Reserves are frequently constrained in design and size by various financial, social or political factors. Maintenance of existing reserves must therefore rely on strategic management practices, and prioritization of conservation activities within them. Identification of global and regional hotspots have been effective for prioritizing conservation activities. Yet, identification of micro-hotspots, or overlapping areas of endemic and rare species that are under threat at the landscape scale, have largely been ignored. From a reserve management point of view, knowledge of critical micro-hotspots within a reserve, are focal points for directing cost effective, conservation initiatives, especially removal of invasive alien plants which are a major threat to biodiversity.Using diversity patterns of dragonfly assemblages, many endemic and threatened, within a biosphere reserve located in the core of a global biodiversity hotspot, we investigated the concept of micro-hotspots. As biosphere reserves contain zones with varying degrees of anthropogenic impact, we also investigated the value of buffer and transition zones for complementing the dragonfly fauna of the reserve core. We found a distinct micro-hotspot within the protected core zone which shows concordance for both endemism and species richness. We conclude that focused conservation actions to remove invasive alien plants within this micro-hotspot would help insure its continued integrity. Furthermore, while there is greater habitat degradation within the buffer and transition zones, they support many additional species, but not those necessarily endemic or threatened. The complementary value of buffer and transition zones therefore lies in increasing habitat heterogeneity and species richness of the whole reserve.  相似文献   

5.
As the area of the world’s forests shrinks, the management of production forests is becoming increasingly paramount for biodiversity conservation. In the United States and Australia, public debate and controversy about the management of production forests during the later decades of the 20th century resulted in governments adopting sweeping top-down changes to forest policy, with regional forest plans a cornerstone of this process. This paper reviews the biodiversity conservation outcomes of two such processes, the Southeast Queensland Forests Agreement (Australia) and the Northwest Forest Plan (United States). Several key lessons are identified. First, these plans are significant steps forward in the struggle to conserve forest biodiversity while providing for production of timber. Second, expanding the conservation reserve system by itself does not necessarily ensure biodiversity conservation, especially if reserves are traded off for increased timber harvesting in forests outside of reserves or if certain important elements of biodiversity are not accounted for either by conservation forests or production forests. Third, reserves often need active management to restore diversity in previously-logged forests and reduce fuels that have accumulated as a result of fire exclusion. Fourth, the current plans fall short of the comprehensive whole-of-landscape, multiple-ownership approach needed to support long-term sustainable forestry and biodiversity conservation. Fifth, adaptive management was not adequately institutionalized and sometimes misapplied, although, in the case of the Pacific Northwest, a major regional monitoring strategy was developed and partially implemented. Finally, ecological science suffered in the collision with the socio-political decision-making process due to the limited scope that was left for testing and evaluating the new approaches to forest management. We conclude, based on the evaluation of the two regional plans, that regional biodiversity conservation goals may be better achieved by implementing sustainable forest management practices across all ownerships and involving all stakeholders and the broader community.  相似文献   

6.
Protected areas established for wildlife conservation (IUCN category I-VI protected areas) or for forest and watershed conservation (forest reserves) across mainland sub-Saharan Africa have high biodiversity values. However, they fail to cover over half of the 106 threatened bird species, and thus leave these vulnerable to extinction. An analysis of Red List bird species that are not represented in existing reserves indicates gaps in the current network of protected areas, namely: Mt. Cameroon-Bamenda highlands (Cameroon), the Angolan scarp (Angola), the Drakensberg Highlands (South Africa), the Highveld (South Africa), the Eastern Arc Mountains (Tanzania), the eastern African coastal forest mosaic (Kenya and Tanzania), the Albertine Rift (Uganda, Rwanda, Burundi, eastern Democratic Republic of Congo and western Tanzania), and the Ethiopian Highlands. The addition of Forest Reserves to the existing protected areas closes some of the reservation gaps for threatened birds in Africa. We suggest that these Forest Reserves should be included within official lists of protected areas, and that National forestry authorities be encouraged to manage these areas. Publication of scientific articles showing the conservation value of Forest Reserves is needed to raise local and international support and funding.  相似文献   

7.
Anthropogenic activities have resulted in extensive deforestation and forest degradation on many tropical oceanic islands. For instance, some islands in the Solomon archipelago have as little as 10% of primary forests remaining with few of these remnants protected from future land use change. We examine the plant species and functional diversity (excluding adult canopy trees) of 48 sites from four forest land use types (two types of primary forest, secondary forest and abandoned tree plantations) and two common human-maintained land use types (coconut plantations and grazed pastures) across three elevation bands on Kolombangara Island, Solomon Islands. In total, we surveyed 384 species from 86 families of which only 6.5% were non-native. Species richness was lowest in coconut plantations and grazed pastures and declined with increasing elevation across all land use types. Functional diversity was similar between primary and secondary forest (high richness, high evenness and unaltered dispersion) and lowest in coconut plantations and grazed pastures. Our results suggest that species and functional richness have had divergent responses to land use change in forest land uses indicative of a loss of functional redundancy. Despite structural and compositional similarities among primary forests and degraded forest land uses, full recovery of secondary and commercial plantations has not been achieved. We suggest that conservation of Kolombangara’s forest understory flora will require reserves across the island’s elevation gradient and may require active restoration in the future, particularly if degrading activities continue at the current rate.  相似文献   

8.
Many existing parks are currently experiencing difficulties in achieving their conservation aims, yet they remain an important option for maintaining and enhancing the conservation of biological diversity and ecosystem processes. Critics have claimed that many national parks cannot continue to protect the biological resources within their borders, and the sustainability of these areas over the long-term is in question. Ways need to be found to strengthen those that are failing, and to understand and replicate those that are succeeding. This paper presents the empirical results from a systematic evaluation of how effectively six case study national parks and national park reserves in Canada and South Africa have been protecting ecological integrity. Several parks were effective at addressing the priorities for which they had monitoring data, however the effectiveness rating of each park decreased when all indicators, including those identified as priorities but lacking monitoring data, were analysed. This indicates that the parks had generally identified more priority indicators than they were actually able to address (for many reasons, including lack of budget or trained staff, managerial challenges). Overall, a systematic approach to evaluating ecological integrity in national parks is recommended as the managers of protected areas cannot be expected to conserve the biological diversity and ecosystem processes within their borders if they are unaware of the ecological status of the park’s biodiversity. The paper concludes with several practical recommendations for monitoring ecological integrity in national parks.  相似文献   

9.
Theoretical advances in systematic reserve design aim to promote the efficient use of limited conservation resources and to increase the likelihood that reserve networks enhance the persistence of valued species and ecosystems. However, these methods have rarely been applied to species that rely on spatially disjunct habitats. We used the marbled murrelet, a seabird that requires old-growth forest in which to nest and high quality marine habitats in which to forage, as a case study to explore methods of incorporating multiple ecological values into single species spatial reserve design. Specifically, we used the cost function in MARXAN to include the ecological value of marine habitats while identifying spatial solutions for terrestrial nesting habitat reserves. Including marine values influenced terrestrial reserve designs most when terrestrial habitat targets were low and little or none of the target was represented in pre-existing protected areas. Our results suggest that including marine values in the planning process will influence marbled murrelet terrestrial reserve designs most where substantial terrestrial nesting habitat still exists, where new reserves are relatively unconstrained by pre-existing reserves, or when conservation resources only allow the protection of a small fraction of available habitat. This paper presents a novel framework for incorporating multiple measures of ecological value in the spatial reserve design process and should be particularly useful for species that rely on multiple habitats during their life cycle.  相似文献   

10.
Traditionally, nature reserves have been centered mainly around areas that are important for vertebrate diversity. This practice has not gone unchallenged and may be a suboptimal choice for overall conservation planning. To investigate this problem, we sampled butterfly species richness in a nature reserve in north eastern Greece that was originally established for the protection of birds of prey. Patterns of butterfly species richness and abundance were investigated by means of transect walks across a range of the seven predominant habitat types (wet and dry meadow, pine, oak and mixed forest, grazed, and agricultural land). Data analysis, including ANOVA and DCA (detrended correspondence analysis), revealed that the main gradients in butterfly species richness (low to high) were from sites dominated by the pine forest matrix of the core areas of the reserve, to peripheral sites in landscapes of mixed or oak forest, and from sites with little human impact to more disturbed areas with high grazing pressure. Species of conservation interest were concentrated at sites of low human impact. Ten of them are endemic to Europe and/or threatened in Europe. In this respect, the most important species are Lycaena ottomanus, Thymelicus acteon, and Pseudophilotes vicrama which are declining all over Europe. Our results suggest that (1) traditional agricultural practices in areas surrounded by forest can be considered as important management tools in butterfly conservation, (2) highest butterfly species richness is found in the periphery of the reserve rather than in the core areas, and (3) for butterfly conservation the zones surrounding the strictly protected areas are equally important as the core areas.  相似文献   

11.
[目的]陆地生态系统中的碳循环和水循环是陆地生态系统物质和能量循环的核心,也是连接地圈、生物圈和大气层的纽带。森林植被是陆地生态系统的重要组成部分,是表征陆地碳-水循环的重要变量,在维持生物圈和大气圈的动态平衡中发挥着重要作用。目前,对陆地生态系统中碳-水循环的耦合关系和机制缺乏系统的分析和总结。[方法]从森林植被碳与水过程及其相互作用、植被水分利用和耦合机制的角度,综述了森林植被碳与水循环过程及其相互作用的研究与进展,以及不同空间尺度(叶片到区域/全球尺度)碳-水耦合的定义、方法、进展和展望。[结果]新兴的技术和方法实现了不同尺度碳水过程的高频观测,WUE等耦合指标体系推动了碳水耦合机制的研究和发展。[结论]通过系统阐述植被碳水耦合关系的多尺度整合和碳水耦合机理,为系统认识森林碳水耦合机理和水资源管理提供了理论基础,对未来植被经营管理决策具有重要的科学支撑意义。  相似文献   

12.
Conserving biodiversity in fire-prone forest ecosystems is challenging for several reasons including differing and incomplete conceptual models of fire-related ecological processes, major gaps in ecological and management knowledge, high variability in fire behavior and ecological responses to fires, altered fire regimes as a result of land-use history and climate change, and the increasing encroachment into forest landscapes by humans. We briefly compare two ecologically distinct fire-prone forest regions, the Pacific Northwest, USA and southeastern Australia with the goal of finding ecological conservation generalities that transcend regional differences as well as differences in scientific concepts and management. We identify the major conceptual scientific and conservation challenges and then present a checklist of questions that need to be answered to implement place-based approaches to conserving biodiversity in fire-prone forest ecosystems. The two regions exhibit both similarities and differences in how biodiversity conservation is conceptualized and applied. Important research and management challenges include: understanding fire-prone systems as coupled natural-human systems, using the disturbance regime concept in multiple ways, dealing with large fire events, using language about the effects of fire with more precision, and researching and monitoring fire and biodiversity at multiple spatial scales. Despite the weaknesses of present conceptual models, it is possible to develop a checklist of principles or questions that can be used to guide management and conservation at local scales across systems. Our list includes: establishing the socio-economic context of fire management, identifying disturbance regimes that will meet conservation goals, moving beyond fuel treatments as a goal, basing management goals on vital attributes of species, and planning for large events including post-fire responses.  相似文献   

13.
Mexico currently has 144 nature reserves covering approximately 9.1% of its land area. These reserves were established for a variety of reasons—often unrelated to the protection of biodiversity. In 2000 in response to a growing concern about the lack of organized conservation reserve planning to protect the important threatened biological and physical features of Mexico, the Mexican Commission for Knowledge and Use of Biodiversity (CONABIO) proposed the establishment of 151 new reserves for Mexico covering 51,429,500 ha. We compiled a GIS analysis using digital thematic maps of physical and biological features to examine how the existing and proposed reserves serve to protect the biodiversity and physical features of the country. Using a conservation target of placing a minimum of 12% of the land area of each important biophysical feature in nature reserves, we found that the 144 existing nature reserves covering 18 million ha (9% of the country) only meet that target for elevation ranges >3000 m and areas with poor soils. These mountainous areas represent less than 1% of the country. The gaps in the existing nature reserves network occur mainly at lower and intermediate elevations (<3000 m) areas with xeric, tropical, and temperate ecosystems, and high productivity soils. The areas proposed by CONABIO increase the proportion of protected lands in the country to over 27% and most of the conservation targets for geophysical features, and land cover, categories are met. Whether this area would be sufficient to maintain viable populations and ecological integrity of species and ecosystems is unknown. Even with the new reserves, low elevation coastal lands would be below the conservation target in the nature reserves. To include a representative sample of these lands would be difficult as these are the same areas where the majority of people live.  相似文献   

14.
Biological reserves are intended to protect species, communities, and ecosystems in human-dominated landscapes. However, existing protected areas represent only relatively small, geographically biased samples of species and habitats. Climate change and habitat loss can exacerbate these biases and the net result is a small, skewed subset of historic environmental conditions. We developed a general model to improve the representation of environmental conditions across the range of at-risk species or any other elements targeted for conservation. We implemented the model as an integer linear-programming problem to select additional areas to complement existing reserves and create new portfolios that are bioclimatically representative across a range of climatic scenarios. We demonstrated the use of the model for a small dataset including two hydrologic variables across the range of five species of fairy shrimp (Anostraca) in the Central Valley ecoregion of California, USA under three climate scenarios. The bioclimatic representation model identified solutions that meet biodiversity representation goals and substantially improve bioclimatic representation at minimal additional cost in terms of total land selected for a conservation portfolio. Additional constraints rewarding bioclimatic representation under two conflicting climate scenarios resulted in only a small decrease in the performance of solutions with respect to current climate. We conclude that this model provides a general tool for improving bioclimatic representation, and results from the Central Valley case study suggest an encouraging, testable hypothesis that climatically robust bioclimatic representation can be achieved at negligible marginal costs.  相似文献   

15.
Protected areas are valuable tools for nature conservation but the effectiveness of reserve networks must be monitored continuously. Knowing the history of the establishment of protected areas can help to improve future conservation. We explore how different ecoregions, ecosystems and diversity hotspots have been incorporated in protected areas in Estonia during the last century. We found that the average rate of establishment of protected areas has been surprisingly constant despite profound changes in political systems. However, establishment of protected areas has varied regionally; an agricultural region in south-east Estonia has seen less protection, partly due to lower biodiversity. Wetland ecosystems were initially more placed under protection, whereas recently semi-natural grasslands have gained more attention. In contrast, farmland is under-protected. Surprisingly, biodiversity hotspots were no more protected than the national average. We consider how the development of a protected area network has been influenced by individual persons and public opinion under successive political systems. We suggest that simultaneous gap analysis of ecoregions, ecosystems and diversity hotspots provides a more complete picture than examining a single aspect. Therefore this study can be used as a model for other regions.  相似文献   

16.
Developing a predictive theory for species responses to habitat fragmentation is a large, complex challenge in conservation biology, and meeting this challenge likely requires tailoring predictions to specific habitats and taxa. We evaluate the effects of fragmentation on forest birds living in three distinct forest ecosystems found in Brazilian Atlantic forest: seasonal semi-deciduous forest (SF), mixed rain forest (MF), and dense rain forest (DF). We test the hypotheses that (1) bird species most prevalent in SF (relative to other habitat types) will be least vulnerable to population declines in fragmented SF, and (2) species with stronger affiliations with DF or MF will be relatively more sensitive to fragmentation in SF. Using an exploratory statistical technique called “Rank Occupancy–Abundance Profiles (ROAPs),” we compared distribution and abundance of birds among large “continuous” areas of each forest type, then compared abundances in continuous SF forests with patterns of abundance in small fragments of SF, where edge effects could play a marked role in population dynamics. Overall, 39 species showed substantially lower local abundance, occupancy, or both in SF fragments versus continuous SF. As predicted, a higher proportion of bird species associated with DF appeared sensitive to fragmentation in SF; by contrast, species most abundant in SF and MF were similarly abundant in fragmented SF. Our study demonstrates how quantifying distribution and abundance in diverse habitats may enhance managers’ ability to incorporate species-specific responses to human disturbances in their conservation plans, and points out ways that even small reserves may have significant conservation value.  相似文献   

17.
The complex geological history of Italy is responsible for the remarkable number of different landscapes and ecosystems present today. The immigration of animals and plants from neighbouring lands, when natural bridges were available, the survival of warm species along the coast during the Quaternary glaciations, and the relict populations which remained in the Apennines after the withdrawal of the ice, have all contributed to the richness of wildlife. In order to preserve adequately this biotic variety it is necessary to protect a large number of separate areas as National or Regional Parks or as nature reserves. In addition, the existence of important bird migration routes along or across the Italian peninsula and islands makes it necessary to provide safe areas where these birds can rest and feed. In spite of these needs, the State and the Regional Governments are not sufficiently concerned with wildlife and environmental conservation and so far have done very little to improve the protection of nature in Italy. In this paper 56 main areas are discussed which are in urgent need of protection from commercial speculation and the threat of irreparable damage. The authors hope that national and international public opinion will encourage the Italian Government to establish many more protected territories and to provide the resources for realistic management.  相似文献   

18.
Human-modified tropical landscapes under semi-natural or agro-ecosystems often harbor biodiversity of significant conservation value. In the Western Ghats of India, these ecosystems also provide connectivity between protected areas and other remnant forests. We investigated the conservation value of these landscapes and agro-ecosystems using results from 35 studies covering 14 taxonomic groups. Large, conspicuous taxonomic groups and tree-covered land-use types have received much focus in this area of research in the Western Ghats. We computed a response ratio defined as the log ratio of species richness in human land use to species richness in forest control site from 17 studies. In a meta-analysis, we investigated variation of this ratio across studies with respect to three variables: taxonomic group, the land-use type sampled and the extent of forest cover within the study landscape. Higher forest cover within the landscape emerged as a major positive influence on biodiversity in human-modified landscapes for vertebrates and vegetation while no patterns emerged for invertebrates. Our results suggest that loss of remnant forest patches from these landscapes is likely to reduce biodiversity within agro-ecosystems and exacerbate overall biodiversity loss across the Western Ghats. Conservation of these remnant forest patches through protection and restoration of habitat and connectivity to larger forest patches needs to be prioritized. In the densely populated Western Ghats, this can only be achieved by building partnerships with local land owners and stakeholders through innovative land-use policy and incentive schemes for conservation.  相似文献   

19.
Mountain ecosystems are often identified as being particularly sensitive to climate change, however this has rarely been investigated at the scale of individual mountain ranges using local relationships between plants and climate. This study uses fine resolution data to assess the potential changes to internationally important Arctic-alpine plant communities in three national nature reserves in the Scottish Highlands, United Kingdom. Distribution models were created for 31 species, representing a range of community types. A relationship between distribution and temperature was found for all species. These models were aggregated to explore potential future changes to each community under two Intergovernmental Panel on Climate Change warming scenarios for the 2080s. The results indicate that Arctic-alpine communities in these reserves could undergo substantial species turnover, even under the lower climate change scenario. For example, Racomitrium-Carex moss-heath, a distinctive community type of the British uplands, could lose suitable climate space as other communities spread uphill. These findings highlight the need to maintain these communities in an optimal condition in which they can be most resilient to such change, to monitor them for signals of change and to develop more flexible conservation policies which account for future changes in mountain protected areas.  相似文献   

20.
The ten National Park Authorities of England and Wales are concerned mainly with landscape conservation and provision for outdoor recreation. Nature conservation is not primary park purpose and only authority has its own nature reserves. Nature conservation purposes are pursued in the parks as elsewhere by the Nature Conservancy Council and by the appropriate County Conservation Trust. The achievements of these two organisations—the former national and governmental, the latter local and voluntary—are compared and contrasted.The number of national Nature Reserves established by the Nature Conservancy nationally assessed. The Conservacy appears to have treated the parks much as it has treated the rest of the country. Local Conservation Trusts have also accorded the parks no more—but also no less—attention than elsewhere. Trust reserves tend to be more or less uniformally distributed throughout the counties of England and Wales. This pattern corresponds with the distribution of Trust members and arises because membership rates tend to be highest in the more rural areas (including the National Parks) where absolute population levels are low. Finally, the National Park Authorities themselves have all but neglected nature conservation purposes in the parks. This lack of interest is consistent with the low priority afforded to nature conservation by local authorities in general and by rural authorities in particular. But whilst past achievements have been slight, future prospects are, by comparison, quite bright.  相似文献   

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