松花江流域(哈尔滨段)景观格局脆弱性高程分异

以松花江流域(哈尔滨段)为研究区域,对研究区域按高程划分分带,在完成2005、2010和2015年3期景观类型提取的基础上,统计研究区域各高程分带景观类型面积,计算研究区各高程分带3期景观格局脆弱性,分析研究区域各景观脆弱性随时间及高程的变化特征。结果表明:1)从2005年到2015年间,研究区域整体景观格局脆弱性呈现先增加后减小的变化。2)不同景观高程分布特征变化明显。耕地、建设用地和未利用地主要分布在低、中高程分带,水域主要分布在低高程分带,林地主要分布在高高程分带。随着高程的增加,耕地、水域和未利用地分布比例大体上逐渐减少,林地、建设用地分布比例增加。草地景观按高程分带并未呈现出规律性的变化。3)从2005年到2015年,低高程分带景观格局脆弱性逐渐降低,中、高程分带景观格局脆弱性均为先增加后降低。随着高程的增加,景观格局脆弱性呈现先增加后减小的变化,中高程分带3期景观格局脆弱性均值最大,为2.2505,高高程分带3期景观格局脆弱性均值最小,为1.9097。

Elevation Differentiation of Landscape Pattern Vulnerability in Songhua River Basin(Harbin Section)

Taking the Songhua River Basin(Harbin Section)as the research area,the study area is divided into three elevation zones according to the elevation,which is the basis for completing the three stages of landscape type extraction of the study area in 2005,2010,and 2015.On the basis of statistics,the areas of landscape types in the elevation zone of each period were calculated,and the vulnerabilities of landscape patterns in the elevation zone of three periods were calculated through the construction formula of landscape pattern vulnerability index.The change characteristics of landscape types and landscape vulnerability over time and elevation in the study area were analyzed.The results show that:(1)From^2005 to 2015,the vulnerability of the overall landscape pattern in the study area increased first and then decreased.(2)Distribution characteristics of different landscape elevation changed obviously.The cultivated land,construction land,and unused land are mainly distributed in the low and middle elevation zones,while waterbody and forest land are mainly distributed in the low and high elevation zones,respectively.With the increase of elevation,the proportion of cultivated land,waterbody,and unused land decreases in general,and the proportion of landscape distribution of forest land and construction land increases gradually.Grassland landscapes divided by elevation did not show regular changes.(3)From^2005 to 2015,the vulnerability of low-elevation zoning landscape pattern gradually increased.The vulnerability of landscape pattern in middle and high elevation zoning landscape pattern increased first and then decreased.In general,with the increase of elevation,the vulnerability of landscape pattern increases first and then decreases.The average vulnerabilities of landscape pattern of three stages in middle and high elevation zones have the maximal and minimal values of 2.2505 and 1.9097,respectively.