地震灾区受灾典型小流域景观要素斑块特征——以北川县苏保河小流域为例

The Patch Characteristics of Landscape Elements in Typical Damaged Catchment of Wenchuan Earthquake Affected Area A Case Study in Subaohe Catchment of Beichuan

为了促进小江流域生态恢复和景观生态合理规划设计,运用RS和GIS技术,从景观要素斑块特征的角度,对地震灾后北川县苏保河小流域景观格局和破碎度进行初步研究。结果表明:针叶林、阔叶林、灌丛、草地和农田是苏保河小流域的5种主要景观类型,其面积和周长之和分别占全流域的84.51%和73.98%;各景观类型面积大小顺序与周长大小顺序基本一致,但其各个景观要素内各斑块周长和面积分布极不均匀,尤其以阔叶林、道路和沟道最为明显;经受过自然灾害或受人为干扰强烈的区域景观破碎度明显高于植被覆盖区域景观;不同景观斑块形状不一,道路和沟道的形状最不规则,而光板岩形状最接近正方形。

In order to promote the ecological restoration and the more reasonable designing of landscapes in Subaohe catchment, based on the technology of RS and GIS, the ecology principle of landscape was applied to the preliminary analysis of landscape pattern and characteristics of landscape elements there. The fragmentation in Subaohe catchment from the angle of patch results showed that： coniferous forest, broad-leaved forest, shrub, grass and farmland were five main components in Subaohe catchment. The total area and perimeter proportion of the five landscapes accounted for 84.51% and 73.98% of the total in the district, respectively. Of all the different kinds of landscapes, the order of the area was consistent with the perimeter order, while the distribution of the area and the perimeter elements were very uneven in each landscape especially in broad-leaved forest, road and channel. The fragmentation of the landscape which suffered from natural disasters or human disturbance was higher than that covered with vegetation. Different landscapes had different shape, as road and channel were irregular mostly while back scarp was close to square.