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91.
This paper examines the integration of landscape connectivity and ecosystem services. It is based on the assumption that if a habitat within a landscape has a more significant role in connecting with other habitats, it would have a higher ecosystem services value for biodiversity conservation. The Shenzhen River watershed, a cross-border region shared by the city of Shenzhen and the Hong Kong Special Administrative Region in China, was used as a case study. An area-based functional connectivity index, known as the possibility of connectivity (PC), was implemented to examine the temporal and spatial dynamics of the value of ecosystem services for biodiversity conservation over the period from 1988 to 2008. To evaluate the effectiveness of the PC index, a comparison was made between the conventional assessment method for ecosystem services and the proposed method. Results suggest that our proposed method can identify significant reduction of ecosystem services that was not only due to the decrease of habitat size, but also caused by the damage of connectivity among habitat patches. Also, it can identify sites which should have a high priority in restoring the ecosystem services for biodiversity conservation. In conclusion, this study provides a way to consider landscape connectivity in the evaluation of ecosystem services which is essential for landscape planning and nature conservation. 相似文献
92.
In a Cost-Benefit Analysis (CBA) or an Environmental Impact Assessment (EIA), determining the value that the general public attaches to a landscape is often problematic. To aid the inclusion of this social value in such analyses, a Google Maps-based tool, called the HotSpotMonitor (HSM), was developed. The HSM determines which natural places are highly attractive by having people mark such places on a map. The definition of attractiveness remains open to avoid having marker placement being influenced by preconceived thoughts. The number of markers an area receives is considered to indicate its social value. Six regions were selected, and from these, stratified samples were drawn (total n = 3293). Participants placed markers at three spatial levels: local, regional and national. This paper focuses on the markers at the national level. The first research question is whether the HSM can produce an accurate map of highly attractive places at a national level. The results indicated that while in principle HSM can produce such a map, the spatial representativeness of the sample is important. The region of origin of the participants influenced where they placed their markers, an effect previously termed spatial discounting. The second research question considers which qualities the participants associate with the marked places. These qualities were very similar at all three spatial levels: green, natural, presence of water and quiet were often selected out of the fourteen suggested qualities. The third, and more exploratory, research question concerns which characteristics of an area predict its attractiveness. Natural and forest areas had higher marker densities than water surfaces or all other types of land use combined. The discussion evaluates the potential of the HSM to generate input on social landscape values for CBAs and EIAs. 相似文献
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W. Siyuan L. Jingshi Y. Cunjian 《International journal of geographical information science》2013,27(10):1077-1092
Using Landsat TM data from 1995 and 2000, changes in the landscape erosion pattern of the Yellow River Basin, China were analysed. The aim was to improve our understanding of soil‐erosion change so that sustainable land use could be established. First, a soil‐erosion intensity index model was developed to study soil‐erosion intensity change in the study area. Over the 5 years, the areas of weak erosion, moderate erosion, severe erosion, and very severe erosion all increased. The area of weak erosion increased dramatically by 7.94×105 ha, and areas of slight erosion and acute erosion decreased by 1.93×106 ha and 4.50×104 ha, respectively. The results show that while the intensity of soil erosion has gradually been decreasing as a whole, in some regions the soil erosion is becoming more severe. Based on landscape indices, the pattern of changes in soil erosion over the past 5 years was analysed. The changes in landscape pattern of soil erosion resulted from human activities. Analysis showed that human impact increases fragmentation, having three major effects on landscape pattern, reduction in patch area, variations in patch shape, and changes in spatial pattern. In the study area, population growth, farming, governmental policy and forest degradation are the major factors causing soil erosion change over a 5‐year period. 相似文献
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The urgency of restoring ecosystems to improve human wellbeing and mitigate climate and biodiversity crises is attracting global attention. The UN Decade on Ecosystem Restoration (2021–2030) is a global call to action to support the restoration of degraded ecosystems. And yet, many forest restoration efforts, for instance, have failed to meet restoration goals; indeed, they worsened social precarities and ecological conditions. By merely focusing on symptoms of forest loss and degradation, these interventions have neglected the underlying issues of equity and justice driving forest decline. To address these root causes, thus creating socially just and sustainable solutions, we develop the Political Ecology Playbook for Ecosystem Restoration. We outline a set of ten principles for achieving long-lasting, resilient, and equitable ecosystem restoration. These principles are guided by political ecology, a framework that addresses environmental concerns from a broadly political economic perspective, attending to power, politics, and equity within specific geographic and historical contexts. Drawing on the chain of explanation, this multi-scale, cross-landscapes Playbook aims to produce healthy relationships between people and nature that are ecologically, socially, and economically just – and thus sustainable and resilient – while recognizing the political nature of such relationships. We argue that the Political Ecology Playbook should guide ecosystem restoration worldwide. 相似文献
98.
基于分形维数和信息熵的土地利用景观格局变化研究——以西安市为例 总被引:3,自引:0,他引:3
信息熵和分形理论为研究地理学中系统的有序性和复杂结构现象的不稳定性提供了一条新途径,为研究土地利用景观格局变化提供了新的思路。以信息熵和分形理论为指导,在遥感和GIS技术支持下,对西安市土地利用景观格局演变的分形特征和信息熵进行分析,结果表明:1999-2008年,西安市土地利用景观结构趋于简单化,景观类型在空间上的稳定性逐渐增大;土地利用景观结构信息熵总体上呈逐渐下降趋势,即土地利用有序度逐渐上升,而无序度逐渐降低。 相似文献
99.
基于GIS和景观生态学的土地整理景观研究 总被引:1,自引:0,他引:1
运用GIS技术和景观生态学理论方法,以安徽省淮南市潘集区市级投资重点土地整理项目为例,选取3类景观指标,对项目区内土地整理前后的土地利用现状和景观格局变化情况进行研究。结果表明: 景观类型中水田斑块占绝对优势,斑块分维数、形状指数呈下降趋势,表明斑块形状趋于规则和简单; 斑块数量和斑块密度降低,平均斑块面积和最大斑块面积增加,最大斑块指数增大,景观破碎度降低; 平均分维数和平均形状指数增大,表明景观形状较整理前变得规则,但总体形态变得复杂; 多样性指数和均匀度指数降低,表明在增加了景观分布均匀程度的同时降低了景观的多样性,景观类型有所减少。 相似文献
100.