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151.
Conservation and protection of soil and water resources and visual aspects of landscape, as well as the promotion of biodiversity, are some of the central tasks of environmental policy development and social politics in the future. One of the main questions is: ‘which agricultural systems are able to guarantee sustained resource-conserving land use?’ Based on the ecological risk concepts of the 1970s and 1980s, a potential impact model was developed using a universal assessment algorithm derived from fuzzy logic. The model estimated the potential impact of agricultural land use on ecosystem function using a few resource indicators. Intervention intensities of agricultural land-use are set in relation to site conditions and aggregated for each of several defined potential impact categories. The interpretation with respect to risk and the calculation of potential impact values are explained.  相似文献   
152.
The objective of this research work is the evaluation of the impact of landuse pattern and intensity on landscape by means of an indicator. The method used to calculate a ‘landscape indicator’ (Iland) allows to take into account the objective as well as the subjective approach of landscape. Iland corresponds to the degree of agreement between landscape supply by farmers and landscape demand by the social groups. The supply and the demand are evaluated through four criteria: ‘diversity’, ‘upkeep’, ‘openness’ and ‘heritage’. The landscape supply is calculated from data of landscape objects (punctual, linear and spatial) for each criterion recorded at the field level. The values of the four criteria for the landscape demand are allocated by the user(s) of the indicator (decision makers, regional council, social groups…) into five classes (0–4). The value of the landscape indicator is the least favourable difference between supply and demand for the four criteria. An example of calculation of the ‘landscape indicator’ for an arable farm is given. The collection of data needs 2 h with the farmer and 2 h for a survey of the farm land.  相似文献   
153.
珠江三角洲典型区景观生态聚类分析   总被引:7,自引:2,他引:7  
珠海是珠江三角洲地区一个海陆交互作用与人类干扰活动频繁的典型区域。文章以2000年TM数据为基础数据源,编制珠海地区景观类型图,并以镇(区)为基本空间单元将珠海划分为20个景观生态子区,在GIS与景观斑块分析软件Patch Analyst 2.0支持下计算各子区的景观特征指数。通过各子区的景观指数对比分析,探讨研究区范围内景观格局的空间差异,揭示人类活动、自然干扰等各种景观生态机制对区域景观生态的影响。根据各指数反映的景观特征信息,选择平均斑块大小(MPS)、斑块大小变异系数(PSCOV)、边缘密度(ED)、面积加权分维数(AWMPFD)、破碎度指数(F)、多样性指数(SDI)及人为干扰指数(DT)进行珠海景观生态聚类分析,根据聚类分析结果可多层次客观地对珠海地区进行景观生态类型区划分。  相似文献   
154.
再生水用于都市绿地灌溉的研究进展   总被引:8,自引:0,他引:8  
污水再利用具有节水和治污双重功能,用于绿地灌溉意义重大。综述了再生水灌溉对绿地土壤、植物、地下水的影响。着重介绍了国外的研究情况,分析了其试验结果及影响因素,表明虽然再生水中的一些有害成分会发生积累,但由于处理工艺、降雨等因素影响,对绿地生态系统影响不大,使用再生水灌溉绿地是切实可行的。  相似文献   
155.
This article is the third in a series prepared to explain the Teller County growth management planning process. Once it was determined by local decision-makers that Teller County, Colorado, would pursue a policy of directed growth, concepts based on this policy were developed. These concepts presented visions and options for the future. Landscape plans then were developed for Teller County and the City of Woodland Park planning area so that these options could be visualized by local leaders and the public. The landscape plans were used as part of the ongoing citizen involvement process to inform the public about the options for growth management. To provide even more information, detailed designs were developed for specific areas in the county. From the landscape plan, public involvement effort, and detailed designs, specific implementation measures were identified, discussed, and adopted. These measures included guidelines for administration, so that county and city goals could be linked to the actual day-to-day management of development proposals. Paper 3 in a series of 3.  相似文献   
156.
The United Kingdom offers some of the finest designed parks and garden landscapes in the world and, whilst there is a wide range of skills and a wealth of literature on the subject, there is little evidence of official effort to systematically record historic sites. This, it is argued, is a factor in the continuing decline of many examples. This paper records an attempt at a comprehensive examination of one county — Cheshire — begun in 1970. The method is described and the results discussed in some detail. Some suggestions are put forward for improvements to official incentives for site owners.  相似文献   
157.
The value placed by the public on the nation's rural landscapes is emphasised by vociferous criticism of insensitive, large‐scale afforestation. As forestry causes massive changes in the landscape in the short term, with results that last for decades, the opportunity provided to improve and conserve should be positively grasped. There is evidence that concensus exists over a considerable part of landscape and design, and this paper explores some of the major factors in landscape design which are consistently important in forest landscapes.  相似文献   
158.
城市快速路景观影响评价方法探讨   总被引:2,自引:0,他引:2  
首先介绍了国内外道路景观影响评价发展状况和意义,给出了城市快速路景观及视觉影响评价的基本概念、步骤和方针;结合常用的景观影响评价方法,充分考虑工程实践中时间性、准确性要求形成了一套具有较强操作性的景观影响评价方法。在该方法中对指标的概念和标准化处理方法做了改进,计算函数更为实用和完备,并充分考虑了公众关注度的因素,体现了观念的更新。最后给出了对视觉影响的缓解措施和改进意见。  相似文献   
159.
采用生态环境影响评价中的景观生态学方法 ,结合景观生态学的评价要求 ,从景观空间结构、恢复能力、内在异质性、绿色拼块之间的连通程度以及组织开放性等方面 ,对重庆市二郎科技园区规划的景观生态作出评价和预测 ,提出园区生态建设应注意的问题和采取的措施 ,以推动二郎科技园区的生态建设和经济、社会的可持续发展。  相似文献   
160.
区域开发生态影响评价方法及应用   总被引:7,自引:0,他引:7  
建立一套系统的区域生态影响评价方法,对于区域环评和环境的可持续发展具有重要的意义。以济南舜湖社区区域开发为例,建立和应用由生态指标法、图形叠图法、景观生态学方法构成的方法体系,对舜湖社区区域开发生态环境影响进行了评价,并提出生态保护和建设的具体措施。结果表明,3者构成的方法体系,能较全面的反映生态环境质量现状,预测生态环境影响,有较为广泛的应用前景。  相似文献   
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