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261.
The premise of this article is that the planning and design of new rest camps in conservation areas should be based on ecological principles in such a way that the plant ecology within the camp be an integral part and extension of the natural ecology of its immediate vicinity. This is desirable so that visitors to the camp will be provided not only with facilities for resting, eating, and sleeping, but also be able to enjoy and study the natural environment in a relaxed atmosphere. The Berg-en-Dal rest camp, which was established in Kruger National Park, was planned in such a way and designed according to the principles outlined by the authors in a companion article. The planning included six zones: a control zone, day visitor zone, overnight visitor zone, staff accommodation zone, recreation zone, and service zone. The point is stressed that plant species selected to be used as additional vegetation to those already growing in the camp were endemic to the nine landscape facets identified in the camp. The design allowed for separation of the various land-use zones in such a way that they would complement each other rather than be a hindrance to each other. The camp has been built according to the plans included in this article and has proved to be a great success. The conclusion is drawn that the planning principles are sound and should be used in the future for the planning and design of rest camps for conservation areas in South Africa.  相似文献   
262.
Evidence from cross-sectional growth regressions suggests that economies dependent on natural resource exports have had slower growth than resource scarce economies. Explanations for this “curse of resources” focus on institutional and market failures caused by resource abundance. With a simple two sector model exhaustible resource model, we demonstrate that the correlation between growth and natural resource abundance can be negative in the absence of market and institutional failures. Since there is no way to distinguish between efficient and inefficient equilibria on the basis of the negative correlation between growth and resource abundance, finding that correlation is not sufficient to conclude resources are a curse, nor is it necessary to find a positive correlation between growth and resources to overturn the resource curse interpretation. We show whether resources are a curse or a blessing for an economy can only be determined by an investigation of the correlation between resource abundance and income levels. Using panel data for U.S. states for the period 1970-2001, we show that resource abundance is negatively correlated with growth rates but positively correlated with income levels.  相似文献   
263.
Modeling the spatial dynamics of regional land use: the CLUE-S model   总被引:92,自引:3,他引:92  
Land-use change models are important tools for integrated environmental management. Through scenario analysis they can help to identify near-future critical locations in the face of environmental change. A dynamic, spatially explicit, land-use change model is presented for the regional scale: CLUE-S. The model is specifically developed for the analysis of land use in small regions (e.g., a watershed or province) at a fine spatial resolution. The model structure is based on systems theory to allow the integrated analysis of land-use change in relation to socio-economic and biophysical driving factors. The model explicitly addresses the hierarchical organization of land use systems, spatial connectivity between locations and stability. Stability is incorporated by a set of variables that define the relative elasticity of the actual land-use type to conversion. The user can specify these settings based on expert knowledge or survey data. Two applications of the model in the Philippines and Malaysia are used to illustrate the functioning of the model and its validation.  相似文献   
264.
Participatory environmental and resource management is premised on open communication to reach consensus. However, deliberate and open communication cannot adequately address silent conflict. This begs two questions. First, how is the existence of covert communication and silent conflict to be recognized and addressed? Second, how are the wider social relations and traditions that encompass communication and conflict to be described and explained? These questions revolve around communicative power. Communication of environmental knowledge is deeply embedded in social power structures, with direct implications for participatory resource planning and implementation. Ethnographic research conducted at a failed community-managed fish farming project in Southeast Sulawesi, Indonesia shows that a culture of harmony and respect for authority can silence environmental conflict in the hierarchical “community.” Three propositions are offered. First, communication amnesia and exclusion jeopardize participation. Second, cultures of harmony and silent conflict shape planning processes and outcomes. Third, the weak use manipulation and communication strategy to acquire a “voice” while preserving harmony. These propositions address five unresolved issues in participatory resource management: analysis of groups, contextuality, social relationships, nonparticipants, and informal communication. Power, tradition, and social networks affect the valuing of knowledge relative to the power of different individuals and institutions to communicate priorities, values, and needs. These factors are critical to the inclusion of both participants and nonparticipants.  相似文献   
265.
266.
The core element of the Costa Rican forestry policy is a financial instrument called the environmental service payment. This instrument rewards forest owners for the environmental services (the mitigation of greenhouse gases, the protection of watersheds and scenic beauty, and the development of biodiversity) their forests provide. In this article, the experiences with this new instrument are analyzed by focusing on the way interests are represented and access is granted, the openness of information exchange, whether social learning occurred, and whether decision-making authority is shared. The analysis is based on a survey conducted in the Huetar Norte Region and on in-depth interviews with the major stakeholders. The Costa Rican case indicates that financial instruments can be used to share responsibilities and that stakeholders can successfully cooperate on forest issues. It also shows that such a participatory approach is only promising if certain cultural, economic, organizational, and political conditions are met.  相似文献   
267.
Geographical areas constitute the basic implementation locus for integrated coastal zone management strategies and activities. Because the definition of territorial planning objectives may be affected by socioeconomic and environmental characteristics, one of the main steps in the process involves dividing the coast into homogeneous environmental management units (HEMUs). This article presents a general and simple method for regionalizing the landside of a coastal zone into HEMUs and illustrates it through application to the Catalan coast. Socioeconomic and natural (biophysical) subsystems were selected as the most appropriate dimensions of the regionalization process. Dimensions were described using 11 spatial themes, which were managed in a geographic information system environment that proved to be an adequate tool for the purpose. A final coastal zone map of four classes of HEMUs connected to local administrative units was obtained, and because it reflects the current natural and socioeconomic dynamics, it can be considered as an initial step in the planning process for the Catalan coast. Although the proposed method was developed based on the characteristics of the Catalan coast, it is general enough to be adapted and applied to most developed or developing coastal areas.  相似文献   
268.
Tourism infrastructure such as walking tracks can have negative effects on vegetation including in mountain regions. In the alpine area around continental Australia's highest mountain, Mt Kosciuszko (2228 m), there is a range of walking tracks (paved, gravel and raised steel mesh surfaces) in addition to an extensive network of informal/non-hardened tracks. Vegetation characteristics were compared between track types on/under tracks, on the track verge, and in the adjacent native vegetation. For a raised steel mesh walkway there was no difference in vegetation under the walkway, on the verge, and 3m away. In contrast, for a non-hardened track there was 35% bare ground on the track surface but no other detectable impacts. Gravel and paved tracks had distinct verges largely comprising bare ground and exotic species. For non-hardened tracks there was an estimated 270 m2 of disturbance per km of track. For wide gravel tracks the combined area of bare ground, exotic plants and gravel was estimated as 4290 m2 per km, while for narrow gravel tracks it was estimated as 2940 m2 per km. For paved tracks there was around 2680 m2 per km of damage. In contrast, there was no detectable effect of raised steel mesh walkway on vegetation highlighting some of the benefits of this surface over other track types.  相似文献   
269.
Because environmental conservation can remove scarce natural resources from competing uses, it is important to gain support for conservation programs by demonstrating that management actions have been effective in achieving their goals. One way to do this is to show that selected significant environmental variables (indicators) vary between managed and unmanaged areas or change over time following implementation of a management regime. However, identifying indicators that reflect environmental conditions relevant to management practices has proven difficult. This paper focuses on developing a framework for choosing indicators in a coral reef habitat. The framework consisted of three phases: (1) information gathering to identify candidate variables; (2) field-testing candidate variables at sites that differ in intensity of human activity, thus identifying potential indicators; and (3) evaluating potential indicators against a set of feasibility criteria to identify the most useful indicators. To identify indicators suitable to measure the success of a management strategy to reduce anchor damage to a coral reef, 24 candidate variables were identified and evaluated at sites with different intensities of anchoring. In this study, measures that reflected injuries to coral colonies were generally more efficient than traditional measures of coral cover in describing the effects of anchoring. The number of overturned colonies was identified as the single most useful indicator of coral reef condition associated with anchoring intensities. The indicator selection framework developed here has the advantages of being transparent, cost efficient, and readily transferable to other types of human activities and management strategies.  相似文献   
270.
秦皇岛市区内生态类型多样,各类生态系统功能突出,自然资源丰富,尤其是海、旅游资源优势突出,为区域经济发展提供了良好的基础条件。该文对秦皇岛市生态系统平衡及资源开发利用水平进行了定量分析。  相似文献   
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