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391.
景观环境构成在景观评价中的应用   总被引:3,自引:0,他引:3  
提出了分析景观环境构成在景观评价中的重要性 ,并以芜湖市朱家桥水泥粉磨站项目为例 ,说明景观环境构成在景观评价中的应用  相似文献   
392.
水濂洞是南岳风景区系中的一个重要组成部分,本文就水濂洞景区的规划、设计和建筑提出了一些看法。指出在设计时,要重点突出:静、险、古、幽、奇五个特点。  相似文献   
393.
It is usually inappropriate to define rectangular land areas or administrative units as the extent for quantifying landscapes that possess hierarchical structure. As a functional unit established by geophysical relationships, the watershed is one of many natural scales in the hierarchical landscape. We examined the dynamics of the Yashiro watershed of Japan at the landscape level using pattern metrics based on Landsat thematic mapper (TM) imagery from 1985 to 1998. This watershed provides important habitats for the hooded crane (Grus monachus), a vulnerable species. While its world population has remained stable, the number wintering at Yashiro has declined in recent years. Changes in landscape metrics reveal that the spatial pattern within the watershed underwent homogenization due to depopulation of local people and shifts in local energy requirements and forest management policy at Yashiro. Specific changes include: a decrease in bare land area from 6.2% to 1.0% of the landscape, increased forest cover from 69.2% to 76.1%, reduction in patch number from 1194 to 616 and enlarged mean patch size, and a decrease in total edge from 223,740 m to 158,040 m. The rate of change in landscape metrics indicates a rapid change towards homogeneity in the landscape since 1990. The temporal changes in hooded crane populations corresponded to the changes in landscape. An alternative explanation has been proposed that decline of the species is influenced by landscape dynamics affecting both habitat selection and food resources. Conservation at the watershed scale is suggested to be complementary to the current conservation measures of the species.  相似文献   
394.
Landscape Metrics for Assessment of Landscape Destruction and Rehabilitation   总被引:24,自引:1,他引:23  
This investigation tested the usefulness of geometry-based landscape metrics for monitoring landscapes in a heavily disturbed environment. Research was carried out in a 75 sq km study area in Saxony, eastern Germany, where the landscape has been affected by surface mining and agricultural intensification. Landscape metrics were calculated from digital maps (1912, 1944, 1973, 1989) for the entire study area and for subregions (river valleys, plains), which were defined using the original geology and topography of the region. Correlation and factor analyses were used to select a set of landscape metrics suitable for landscape monitoring. Little land-use change occurred in the first half of the century, but political decisions and technological developments led to considerable change later. Metrics showed a similar pattern with almost no change between 1912 and 1944, but dramatic changes after 1944. Nonparametric statistical methods were used to test whether metrics differed between river valleys and plains. Significant differences in the metrics for these regions were found in the early maps (1912, 1944), but these differences were not significant in 1973 or 1989. These findings indicate that anthropogenic influences created a more homogeneous landscape.  相似文献   
395.
森林旅游资源的开发与利用是当今各国森林公园建设所面临的一个重要问题。本文就如何克分利用森林旅游资源,发挥森林景观优势开展多种旅游项目,提出了自己的看法与对策,为发展我国旅游业提供了理论依据。  相似文献   
396.
Incorporation of aesthetic considerations in the process of landscape planning and development has frequently met with poor results due to its lack of theoretical basis, public involvement, and failure to deal with spatial implications. This problem has been especially evident when dealing with large areas, for example, the Adirondacks, Scenic Highways, and National Forests and Parks. This study made use of public participation to evaluate scenic quality in a portion of the Niagara Escarpment in Southern Ontario, Canada. The results of this study were analyzed using thevisual management model proposed by Brown and Itami (1982) as a means of assessing and evaluating scenic quality. Themap analysis package formulated by Tomlin (1980) was then applied to this assessment for the purpose of spatial mapping of visual impact. The results of this study illustrate that it is possible to assess visual quality for landscape/management, preservation, and protection using a theoretical basis, public participation, and a systematic spatial mapping process.  相似文献   
397.
The factor of scale in ecosystem mapping   总被引:2,自引:0,他引:2  
  相似文献   
398.
There are a number of reasons why planners should take a more positive approach towards the natural economy of the city, and this paper rehearses the arguments in favour. The author takes the view that much publicly owned land is manicured and excessively stocked with exotic species so that they are relatively poor in wildlife. An alternative to the generally held view that dormant land in urban areas is unsightly and encourages vandalism, is that such sites offer opportunities for visual interest, education and recreation. The paper concludes by outlining a number of courses of action which, it is suggested, may come to dominate environmental planning.  相似文献   
399.
为探讨沈阳市棋盘山水库湿地保护地近30年生态系统演变规律,文章运用3S技术和景观格局指数,分析了保护地1986~2015年生态系统时空变化及景观格局演变特征。结果表明:1986~2015年间,由于人类活动的干扰,保护地景观破碎度和空间异质性不断增加,水库周边建设用地围绕水库向南部、北部不断扩张,不利于生态系统服务功能的保护和提升,但总体上看,2000~2015年人类活动强度低于1986~2000年,说明该时期生态保护工作取得一定成效。为提升保护地景观质量和生态系统服务功能,提出了保护地生态系统服务可持续管理对策。  相似文献   
400.
融雪剂对园林植物种子萌发的影响   总被引:1,自引:0,他引:1  
李芳  张俊民 《环境科技》2009,22(5):22-24
使用融雪剂是高纬度城市冬季除雪的主要措施之一,但融雪剂中含有的盐类物质可以对园林植物造成伤害。在此研究了融雪剂对刺(Robinia pseudoacacia)、万寿菊(Tagetes erecta)、矮紫薇(Lagerstroemia indiea’Petite pinkie')、草地早熟禾(Poa pratensis)、侧柏(Platycladus orientalis)种子发芽率和相对受害率的影响。试验结果表明:5种植物种子的发芽率随融雪剂浓度的升高而降低.相对受害率则随融雪剂浓度升高而增大。其中草地早熟禾种子时融雪剂最敏感,可以用草地早熟禾种子萌发为指示,间接检验融雪剂对植物的伤害程度。  相似文献   
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