基于GIS的北京市北部城郊绿地景观格局梯度分析

Gradient analysis of urban-suburb green space landscape pattern in Beijing city based on GIS

在GIS技术支持下,基于2009年北京市昌平区2m分辨率的GEOEYE-1遥感影像,采用梯度分析与景观指数相结合的方法,定量分析城郊绿地总体景观格局及大中小斑块类型的景观格局。结果表明:随着城市化强度的降低,城郊绿地斑块整体增加,破碎化程度降低,边界简单化,连通性增大。同时随着城市化强度的降低,小型斑块减小,破碎化程度降低,形状先简单后复杂;中型斑块先增多后减少,破碎程度先增大后减小,边界简单化;大型斑块整体增多,破碎化程度先高后低,边界简单化。随着城区到乡村的转变,绿地结构由小型斑块占优经中型斑块逐步转变为大型斑块为主。另外,所选用的景观格局指数多在城市化边界区出现急剧变化,表明城市化进程对绿地格局有显著影响。

Based on the images from 2009 GEOEYE-1 satellite located in Changping district Beijing and with GIS, the gradient analysis in combination with landscape index was made to study the landscape pattern of urban-suburb green space and large, small, medium-sized patches of green space. The result showed that as the degree of urbanization decreased, patches of urban- suburb green space increased, degree of fragmentation decreased, edge simplified and connectedness amplified. The number and fragmentation degree of small patches decreased as the degree of urbanization decreased; medium patches number and degree of fragmentation increased at first then decreased obviously, edge simplified; the large patches were different from the above. Landscape indices changed fiercely at the boundary of urbanization, which indicated that urbanization could affect the pattern of green space significantly.