流域尺度山区景观格局垂直分异研究

On Landscape Pattern Vertical Differentiation in Mountainous Area at Watershed Scale

本文选取山东省栖霞市内一个典型流域作为研究区,通过选取典型等高线提取附近的景观类型来研究山区景观垂直分异特征,避免以往利用高程带或坡度带进行山区景观格局分析时造成的斑块分割;同时采取坡度分级说明坡度对景观格局分布的影响。研究结果显示:在0-6°坡度范围内,水域和建设用地占据主导位置,在>25°主要景观类型为未利用地,这两个坡度带的景观聚集程度最高,景观类型多呈现连片分布;6-25°坡度带为草坡地、林地、园地和耕地主要分布区域,且这个区域的景观破碎化程度最高;228m等高线附近的景观类型破碎化程度最高、形状最为复杂,是人类活动为主导影响向自然因素为主导影响的过渡区域。在海拔较低区域,由于人类不断对景观格局的优化,景观表现出一定的聚集性和规则化。

Landscape patterns in mountainous area are stratified for the impacts from topologic factors, this paper selected a typical watershed in Qixia City, Shandong province as a case to study the vertical differentiation of landscape pattern by selection and subdivision using contours （138m, 188m, 228m, 308m, 400m, 520m） on the principle of sampling and slope belts （0-6°, 6-15°, 15-25° , 〉25° ） respectively. The results showed that, water body and construction land dominate 0-6° elevation, which have close relation with the development mechanisms of the two landscape types. And AI values both at class and landscape levels show aggregation of landscape pattern in the two belts. The belts between 6°and 25° are dominated by arable land, grassland, orchard and woodland, and corresponding metrics manifest fragmentation. Landscape near contour of 228m shows greatest fragmented than that near lower and higher contours, and the shapes of patches are more complex than other areas, which suggest a transition area from natural factors driving mechanism to human activities driving mechanism that dominates the configuration and development of landscape pattern locally. From the results it also can be seen that, because the optimization of landscape pattern of lower areas, corresponding landscape metrics manifest similar traits as higher areas, which are less impacted by human activities.