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151.
152.
Decline of traditional landscape in a protected area of the southwestern Alps: The fate of enclosed pasture patches in the land mosaic shift 总被引:1,自引:0,他引:1
【Title】
【Author】
【Addresses】1
Traditional landscape elements such as pasture patches enclosed in a forest matrix are progressively disappearing throughout the European Alps. We assessed the land mosaic shift of a protected area located in the western Italian Alps. In particular, the dynamics of pasture patches were studied at both landscape and stand level. Land-cover mapping through object-oriented analysis of historical aerial photographs was used to assess land-cover changes between 1954 and 2000. Spatial statistics were used to quantify landscape patterns, and field samplings within pasture patches were used to explore tree regeneration structure and composition. Our results showed a significant increase in the number of pasture patches caused by their fragmentation following forest expansion. The total surface area of pasture patches decreased by 43% and their core area decreased by 94%. The encroachment of trees on less accessible areas of the pasture patches caused a reduction of patch shape at landscape scale. The gap filling process started 40-50 years ago and began with an early invasion of light demanding species like sycamore maple (Acer pseudoplatanus L.) and common ash (Fraxinus excelsior L.), followed by European beech (Fagus sylvatica L.) and secondarily silver fir (Abies alba Mill.). Traditional land-use and population decline in the Pesio Valley led to a reduction in ecotone areas. A transition to a more homogeneous landscape is expected in the next decades. Given the cultural and productive nature of these mountain meadow-pasture communities, extensive livestock grazing systems could be used to manage their future conservation. 相似文献
【Author】
【Addresses】1
Traditional landscape elements such as pasture patches enclosed in a forest matrix are progressively disappearing throughout the European Alps. We assessed the land mosaic shift of a protected area located in the western Italian Alps. In particular, the dynamics of pasture patches were studied at both landscape and stand level. Land-cover mapping through object-oriented analysis of historical aerial photographs was used to assess land-cover changes between 1954 and 2000. Spatial statistics were used to quantify landscape patterns, and field samplings within pasture patches were used to explore tree regeneration structure and composition. Our results showed a significant increase in the number of pasture patches caused by their fragmentation following forest expansion. The total surface area of pasture patches decreased by 43% and their core area decreased by 94%. The encroachment of trees on less accessible areas of the pasture patches caused a reduction of patch shape at landscape scale. The gap filling process started 40-50 years ago and began with an early invasion of light demanding species like sycamore maple (Acer pseudoplatanus L.) and common ash (Fraxinus excelsior L.), followed by European beech (Fagus sylvatica L.) and secondarily silver fir (Abies alba Mill.). Traditional land-use and population decline in the Pesio Valley led to a reduction in ecotone areas. A transition to a more homogeneous landscape is expected in the next decades. Given the cultural and productive nature of these mountain meadow-pasture communities, extensive livestock grazing systems could be used to manage their future conservation. 相似文献
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在美国加利福尼亚州的莫哈韦沙漠保护区内靠近内华达州界、距离拉斯维加斯约65公里的地方,有一个面积为13平方公里的世界上最大的太阳能热力发电系统,名为“艾文帕太阳能发电系统”(Ivanpah Solar Electric Generating System)。这里每年大约有330-350天都拥有充足的阳光,因而是太阳能发电的理想之所。 相似文献
155.
构建自然保护区特色资源信息系统,对动物、植物、生态旅游等特色资源的有效保护和科学研究具有重要意义。本文在对资源信息特点进行深入分析的基础上,设计了基于GIS的特色资源信息系统,并对数据库设计以及系统实现的关键技术进行了详细阐述。最后以四川省为例,构建了自然保护区特色资源信息系统。 相似文献
156.
针对历史风貌保护区中保护建筑的管理工作,提供文物部门获取基础地理信息的手段,为当地文物保护单位建立起历史风貌保护建筑管理信息系统,并介绍了现代测量技术在文物保护单位数据采集、处理、更新中的应用,分别阐述了现代测量技术在文物保护单位日常管理中发挥的重要作用。 相似文献
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一、保护基本农田的责任追究机制对于占用或破坏基本农田的行为,我国建立了责任追究机制。《土地管理法》第七十四条规定:"违法本法规定,占用耕地建窑、建坟或者擅自在耕地上建房、挖砂、采石、取土等 相似文献