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261.
The country estate has a particular place in the English countryside and its contribution to the landscape scene is distinct and valuable. The paper describes an approach to planning a large country estate of parkland, woodland and estate villages in Cheshire. A Reconnaissance Survey led to the Outline Strategy for six ‘landscape types’ discovered on the estate. The Landscape Conservation Plan is described and the crucial importance of conservation measures is emphasised.  相似文献   
262.
A total of 25 scenes representing the five visual quality objectives in the US Department of Agriculture Forest Service visual management system were presented to 18 professional and public interest groups in western Montana. The results indicate that nearly all the groups have similar rank orderings of the scenes in terms of visual preference. However, the groups differ according to the absolute values of their ratings. Most groups were unable, in a statistical sense, to differentiate the scenic quality of areas in the preservation and retention visual quality objectives. Landscape architects tended to rate scenes in a way similar to professional forest management groups.  相似文献   
263.
The concern of this paper is a review of the urban environmental degradation and the current approach by the military (environmental task force) in solving the problem. It is based on the experience of a few states in Nigeria. The paper proposes a comprehensive urban planning approach which should be integrated with an awareness campaign.  相似文献   
264.
Land use since 1935 was quantified for Georgia, USA, and for a sample of 20 counties from the major physiographic regions within the state. Statistical data on crop production, pasture productivity, and forest growth were used to estimate net primary production. Appropriate harvest indices (ratio of crop yield to total plant production) were used to correct crop yield data for different decades. Net primary production (NPP) of the Georgia landscape increased from 2.5 to 6.4 tonnes/ha from 1935 to 1982, but varied considerably among land uses and physiographic regions. NPP in the piedmont and mountains reached a plateau between 1960 and 1982, but the upper and lower coastal plains showed a continued linear increase in NPP. In all regions, NPP rose most between 1960 and 1982, coinciding with increases in inputs such as fertilizer and irrigation. Natural ecosystem NPP for Georgia is approximately 16–18 tonnes/ha, and the estimated actual NPP is thus considerably less than the potential. Spatial and temporal patterns of NPP may be a useful basis for evaluating the biological performance of a landscape.  相似文献   
265.
Multiple-use forest management has come to include an attention to scenic values, and methods are being developed to incorporate aesthetic considerations into decision making. A considerable body of scientific research has been conducted exploring public preferences for forest landscapes and intersubjective and contextual influences upon their perception. This research is surveyed. Findings regarding the perception of forest conditions, such as tree density and size, ground cover, species makeup and nonmanagement are considered. The scenic effects of forest treatments such as thinning, burning, and chemical application are outlined. Findings for harvest and regeneration practices such as clear-cutting, shelterwoods, selection cuts, and slash treatments are reported. Advances that consider the effects of time upon forest beauty and experiences are explored, along with a problem in multiple-use evaluation of scenic changes. Research on these topics and on observer intersubjective problems and general theory development is supported as a course of advancement in the field.  相似文献   
266.
Natural landscapes produce goods and services, such as fish, wildlife, recreation, climate control, that are not adequately incorporated in their market values. Contingent Valuation (CV) and Energy Analysis (EA) approaches were used to estimate the nonmarket value of forests in Georgia. Both methods yielded similar estimates of approximately $200 ha–1, which was 31% of the total market and nonmarket value of forests. Energy analysis was also used to estimate the nonmarket value of the major land uses in Georgia. Relative contributions of nonmarket value to total value ranged from 0.1% for urban areas to approximately 100% for wetlands. For the state as a whole, nonmarket production of natural and developed ecosystems was estimated at $2.6 billion. This value is comparable to annual marketed agricultural ($2.8 billion) and timber ($4.5 billion) production, both very important industries in Georgia. Changing land use patterns in Georgia and elsewhere are likely to be accompanied by shifts in the relative importances of market and non-market values.  相似文献   
267.
景观生态学与荒漠生态环境监测   总被引:2,自引:0,他引:2  
通过对景观生态的阐述,在讨论荒漠生态环境监测的概念、对象、内容、方法和目的的基础上,分析了景观生态学成为荒漠生态环境监测理论和实践的基础的可能性和必要性,指出景观生态学在荒漠生态环境监测中的应用大有可为。  相似文献   
268.
生物多样性是风景区重要的旅游资源以及环境资源,本文应用景观生态学原理及生物多样性保护的最新理论,探讨了生物多样性保护的方法,包括保护区面积的科学划分以及在面积不足时需要采取的生态学设计,并以黄山风景区为例,对这一理论及方法进行了论证。  相似文献   
269.
270.
Research on perception of parks and recreation settings has examined several important tree attributes that influence people's visual preferences. This research, however, has usually not considered the spatial arrangement of the trees, partly because of the lack of adequate methods for representing tree arrangements with systematically manipulated geometries. In the study reported here, computer video-imaging techniques were used to construct simulated landscape scenes that varied on specific dimensions of the spatial configuration of trees. The simulations were rated for visual preference by three respondent groups: a university class, a bicycle club, and a women's civic group. Preference ratings were significantly influenced by the number of trees in the scene, by the number of clumps into which trees were grouped, and by the diameter of the clumps. The video-imaging technology implemented in this study offers important methodological advantages for the design of carefully controlled experiments to study human response to variation in landscape treatments.  相似文献   
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