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601.
ABSTRACT

Protected areas are widely recognized as an important strategy for biodiversity conservation. Most of the sites are, however, poorly managed as resource exploitation by fringe communities and low government funding, among other things, threaten their management effectiveness. We used the World Commission on Protected Areas framework for designing management effectiveness evaluation systems, with the Rapid Assessment and Prioritization of Protected Areas Management (RAPPAM) methodology as a tool, to evaluate six components of the management cycle at six sites in Ghana for their management effectiveness. We examined the robustness of RAPPAM as an evaluation tool in the African context. The results showed that most of the sites evaluated are vulnerable and exposed to various degrees of pressure and threats, including poverty in the nearby communities, adjacent land-use and encroachment. On RAPPAM, we noted that apart from inconsistencies in some of the assessment scores due to the biases associated with the self-assessment approach of the methodology, the management effectiveness framework places little emphasis on financing and community participation, though both play major roles in the management process. We proposed a modification of the framework within the African context, to address effectively the underlying courses of pressure and threats facing Ghana’s protected areas.  相似文献   
602.
The BOSAWAS Natural Resource Reserve of Nicaragua was established in 1991, to protect a portion of the remaining tropical rain forest and to promote the sustainable use of the region's resources. Information required to effectively manage the reserve includes the extents and locations of present land-cover types and recent land-cover changes in the management use zones that were delineated by local indigenous communities. These zones include areas designated for conservation, limited resource extraction, agriculture, and watershed protection. Land-cover for 1986 and 1995 was identified for three of the communities from remotely sensed images and then input into a geographic information system database to identify land-cover types within these management use zones. For both dates of the analysis, advanced forest was the dominant land cover, with the conservation zones entirely forested. The amount of both agricultural land and scrub/early secondary forest increased between the two dates, with much of these land-cover classes occurring in the agriculture zones. Conflicts between the land-cover present and designated use were identified in some of the limited-use buffer and watershed protection zones. Changes between 1986 and 1995 were identified by overlaying the two land-cover data sets. Three change processes were identified as occurring: deforestation, reforestation, and reconversion. Changes were concentrated in the agriculture zones but were found to occur in every type of zone, except for conservation. The results of this study will establish baseline information for the future management of the BOSAWAS Reserve, an important component in uniting conservation areas along the Central American isthmus.  相似文献   
603.
广西石山区土地石漠化的成因及防治对策   总被引:10,自引:0,他引:10  
石漠化即喀斯特荒漠化、石化,是广西生态环境最突出的问题。为了促进石山区经济的可持续发展,作者采用了文献调查、实地调查、定性分析和定量分析等方法探讨了广西石漠化的成因和防治对策,认为导致广西石漠化加剧的因素是多方面的,既有自然的、更有人为的;其治理也是一个系统工程,需要在释放人口压力、提高人口素质、调整产业结构与布局、加大整治力度、执行财政补偿制度等方面继续努力。  相似文献   
604.
论述了促进环保产业发展的重要性,指出了环保产业发展中应着重解决的问题。  相似文献   
605.
重庆市水环境功能区划   总被引:1,自引:0,他引:1  
运用GIS技术和方法,以1:25万数字地图为基础,通过对重庆市环境现状的调查,结合重庆市的实际情况,提出了水环境功能区划分的原则、工作程序和技术路线,科学地划分了重庆市水环境功能区,并对水环境功能区划中的几个问题作了分析和探讨,提出了合理化建议,对加强环境管理,保护河流水质具有十分重要的意义。  相似文献   
606.
The paper addresses the need for models to assess risk at any particular airport, based on risk management principles used by the present risk management process, that use all available data on previous accidents. The case of runway overruns is taken as an example application, because new regulations require the provision of much longer Runway End Safety Areas than had previously been the norm. The paper presents models for overruns arising from both landings and aborted takeoffs. In each case models of overrun risk, of wreckage location and of the consequences are detailed. An example application of the models is then given in a hypothetical risk assessment.The models, though adding value to existing methods of assessing risk, are not as good as they could be, due to the lack of data on normal operations. It was therefore possible only to relate the rate of overruns to the rate of occurrence of the possible driving factors for a few factors where such comparable data on normal operations existed. It is recommended that effort be put into the collection of data to allow a more comprehensive analysis.  相似文献   
607.
While there has been sustained debate on the issue of provincial and state versus local government environmental planning, maintaining privately owned natural resources in the public interest is increasingly viewed as beyond the scope of local governments alone. This paper describes and compares province- and state-level mandates and options for local governments (i.e., city, county, or district) to regulate land uses of environmentally sensitive areas (ESAs) in British Columbia in Canada and in Washington and Oregon in the United States. We define ESAs as landscape elements or places that are vital to the long-term maintenance of biological diversity, soil, water, and other natural resources, especially as they relate to human health, safety, and welfare, both on-site and in a regional context. Underlying similarities are that all three jurisdictions legally express the need for land-use planning by local governments in managing ESAs. Although all three jurisdictions exhibit similar problems in their attempt to accomplish this, ESA planning by local governments is an optional process in British Columbia and Washington but mandatory in Oregon. Furthermore, actual processes prescribed by each of the three jurisdictions are quite different. The information base upon which local regulation of privately held ESAs depends is variable, both within and between the province- and statelevel jurisdictions. Other than for some specific water-related resources, standard definitions and inventory methods for ESAs are lacking, as is coordination among local governments or among the province- and state-level governments. This study concludes that there is a need for a regional environmental information system in the Pacific Northwest based upon an integrated and scientific approach toward ESA structures and functions.  相似文献   
608.
The protection of wetlands and riparian areas has emerged as an important environmental planning issue. In the United States, several federal and state laws have been enacted to protect wetlands and riparian areas. Specifically, the federal Clean Water Act includes protection requirements in Sections 301 and 303 for state water quality standards, Section 401 for state certification of federal actions (projects, permits, and licenses), and Section 404 for dredge and fill permits. The Section 401 water quality state certification element has been called the “sleeping giant” of wetlands protection because it empowers state officials to veto or condition federally permitted or licensed activities that do not comply with state water quality standards. State officials have used this power infrequently. The purpose of this research was to analyze the effectiveness of state wetland and riparian programs. Contacts were established with officials in each state and in the national and regional offices of key federal agencies. Based on interviews and on a review of federal and state laws, state program effectiveness was analyzed. From this analysis, several problems and opportunities facing state wetland protection efforts are presented.  相似文献   
609.
鞠笑生 《灾害学》1994,9(2):78-82
本文从气候学角度统计、分析了台风登陆或影响我国30°N以南地区8省(浙江、福建、广东、广西、海南、台湾、江西、湖南)而产生风灾的频数分布、季节变化、年变化以及概率分布的特征。  相似文献   
610.
农村生态环境破坏机理初探   总被引:1,自引:0,他引:1  
农村生态环境的破坏已成为制约我国农村经济健康发展的因素之一。在概述我国农村生态环境主要问题的基础上,着重分析了导致生态环境恶化的原因,主要包括工业污染、农业污染、政府行为、城市化建设、农民的环境意识淡薄、环保基础设施薄弱等,并提出了相应的对策。  相似文献   
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