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161.
风景资源是一种不可再生的资源,一旦毁损,无法弥补。随着旅游业的发展,风景资源面临着污染、破坏和衰竭的局面,针对这种现状,本文提出了保护对策。  相似文献   
162.
Structurally complex landscapes may enhance local species richness and interactions, which is possibly due to a higher species pool in complex landscapes. This hypothesis was tested using cereal aphid parasitoids (Hymenoptera, Aphidiidae) by comparing 12 winter wheat fields in structurally complex landscapes (>50% semi-natural habitats; n = 6) and structurally simple landscapes dominated by agricultural lands (>80% arable land; n = 6). Surprisingly, landscape structural complexity had no effect on aphid parasitoid species diversity. In complex landscapes 12 and in simple landscapes 11 species were found; 9 species occurred in both landscape types. Hence, arable fields in high-intensity agricultural landscapes with little non-crop area can support a similar diversity of cereal aphid parasitoids as structurally complex landscapes. This finding suggests that cereal aphid parasitoids may find necessary resources even in simple landscapes, making generalisations concerning the relationship between landscape composition and biodiversity in arable fields difficult.  相似文献   
163.
Metapopulation models assume that inter-patch dispersal dominantly depends on distance between patches and the dispersal capability of organisms in question. We used a spatially explicit, individual-based model to investigate the potential effect of patch constellation on the exchange of individuals between patches. We simulated migration of individuals from a start- into a target-patch with both patches having the same size and shape. Simulation experiments were carried out for four patch constellations and two different movement patterns. Our results demonstrate a substantial effect of patch constellation on the exchange of individuals. They also show that the magnitude and even the direction of this effect crucially depends on their movement pattern. We conclude that particularly for highly correlated movement patterns patch shape and constellation can not readily be ignored when modelling inter-patch dispersal between habitat-islands.  相似文献   
164.
Modeling joint production of wildlife and timber   总被引:2,自引:0,他引:2  
Production of marketed commodities and protection of natural systems often conflict. A focus on only one goal can result in large losses in other goals and may result in inefficient and unsustainable outcomes. In this paper, we develop a method that combines economic and ecological models in a dynamic and spatial analysis to evaluate land use decisions and find cost-effective alternatives for which it is not possible to do better on one objective without harming another objective. The method is demonstrated using timber production and species conservation on a forested landscape over a 100-year planning horizon. Current land use strategies are simulated and compared with cost-effective alternatives. The approach is compared to a static reserve approach, similar to previous studies, and found to produce substantially more efficient management strategies for the case study landscape.  相似文献   
165.
Landscape is becoming an object of growing social concern and, as such, an object of mediation between major industrial producers and local communities. The question of the capacity of environmental assessment to address this issue is thus raised. Until now, landscape studies have focused on visual aspects, although subjective dimensions such as perceptions and meanings have been recognised. The research in this article concerns the subjective dimensions, and is presented with a view to further the understanding of the process of the social interpretation of landscape as it relates to heavy industrial sites. Within a socioconstructivist perspective, two case studies (a longitudinal follow-up and an ex-post) of two aluminum smelters, one in Alma (Quebec, Canada) and the other in Dunkirk (France) were conducted. The results show that nearby residents' interpretations of landscape varied according to three sets of factors related to 1) the dynamics of regional development and the historical place of industry in the community, 2) the relationship between residents and the industry and local governance capacities, and 3) the social impacts experienced. To conclude, three ways of using qualitative methodologies for social and environmental follow-up in a socioconstructivist approach to landscape are proposed.  相似文献   
166.
景观健康及其评价初探   总被引:3,自引:0,他引:3  
生态系统健康是环保领域新兴的、正崭露头角的科学,将生态系统健康科学应用于景观评价是基于人类管理景观严重受到威胁和趋于退化的现实。在论述景观健康概念及其特征的基础上,探讨对景观健康进行整体评价的方法和指标。  相似文献   
167.
Knowledge of the nature conservation value of agricultural land provides a useful input to land-use planning. However, the scarcity of suitable data causes this component to rarely play a role. The paper proposes a methodology based on commonly available data to assess the nature conservation value of agricultural landscapes, and to generate cartographic results to be used as decision variables in planning. The approach relies on landscape ecological indicators and on the application of multicriteria analysis in a Geographical Information System (GIS) context. Four criteria were selected: the agricultural landscape type, the cover of vegetation remnants and marginal features, the length of forest-agriculture ecotones, and the proximity to nature reserves. These criteria were assessed directly or by means of specific indicators, generating maps that were subsequently aggregated through spatial multicriteria analysis. The approach was tested in an alpine area located in Trentino (northern Italy).  相似文献   
168.
This paper develops a comprehensive and objective picture of bird distributions relative to habitats across Britain. Bird species presence/absence data from an extensive field survey and habitat data from the remotely sensed UK Land Cover Map 2000 were analysed in 36,920 tetrads (2 kmx2 km) across Britain (a 65% sample of Britain's c. 240,000 km2). Cluster analysis linked birds to generalised landscapes based on distinctive habitat assemblages. Maps of the clusters showed strong regional patterns associated with the habitat assemblages. Cluster centroid coordinates for each bird species and each habitat were combined across clusters to derive individualised bird-habitat preference indices and examine the importance of individual habitats for each bird species. Even rare species and scarce habitats showed successful linkages. Results were assessed against published accounts of bird-habitat relations. Objective corroboration strongly supported the associations. Relatively scarce coastal and wetland habitats proved particularly important for many birds. However, extensive arable farmland and woodland habitats were also favoured by many species, despite reported declines in bird numbers in these habitats. The fact that habitat-specialists do not or cannot move habitat is perhaps a reason for declining numbers where habitats have become unsuitable. This study showed that there are unifying principles determining bird-habitat relations which apply and can be quantified at the national scale, and which corroborate and complement the cumulative knowledge of many and varied surveys and ecological studies. This 'generality' suggests that we may be able, reliably and objectively, to integrate and scale up such disparate studies to the national scale, using this generalised framework. It also suggests the potential for a landscape ecology approach to bird-habitat analyses. Such developments will be important steps in building models to develop and test the sustainable management of landscapes for birds.  相似文献   
169.
研究了臭氧和光合细菌联合处理景观水体,结果表明,在控制水体pH值为7.5,按照1 L样品通臭氧25 min(每h产生1.5 g)后,在向其中加入4亿个光合细菌大约静置5 d,景观污水将得到较好的净化效果。根据目前的臭氧制取技术,每制取1 kg臭氧约耗电在20 kW·h,按照每分解1 kg COD需要3 kg的臭氧计算,则每处理1 kg COD需要28元左右。较高的运行费用也是这一技术未能大规模应用的主要因素之一。但是该实验利用臭氧和光合细菌联合处理景观水的方法每处理1 kg COD只需要16.5元左右,大大节约了成本,还提高了效率。因此通过臭氧和光合细菌联合处理技术,净化景观水体中的有机物污染和改善景观水体水质,既节约了成本,又达到了很好的效果。  相似文献   
170.
广东省天然气一期总长约466.5km,其中干线长度约369.1km,支干线长约97.4km。项目建设区域包括广州、佛山、肇庆、惠州、韶关、清远和东莞6市。天然气管道建设因其工程特性、施工方式,不可避免对土地利用类型、土壤、植被、动物、农业等方面带来影响,其表征为景观生态的直接影响,由此带来生态系统结构和功能的改变。以广东省天然气一期为例,采用遥感解译和GIS分析技术进行生态影响评价。通过地貌、植被、土地利用现状和现代地理过程等要素的组合,结合景观破碎度、多样性、优势度等指标,定量评价管道建设造成的景观生态影响。选取植被、土壤亮度、湿度、热度等指数,确立各指数权重分后,建立生态评价模型,对生态系统质量进行综合评价,分析管道建设可能造成的生态系统影响。评价区内景观生态类型可分为水域、旱地、水田、林地、草地、建设用地6种,各占6.5%、9.9%、51.2%、25.2%、2.8%和4.3%,破碎度为0.298,均匀度0.743,优势度0.594;生态环境质量可分为良好、中等、较差3类,各占39.8%、26.0%和34.2%。  相似文献   
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