松花江流域哈尔滨段景观生态风险评价

以松花江流域哈尔滨段为研究区域,通过景观易损度指数及景观类型面积比重结合层次分析权重赋值法构建景观生态风险指数,对区域进行景观生态风险的时空变化特征及空间自相关关系进行研究.结果表明:①20年间,松花江流域哈尔滨段景观生态风险整体上呈现先增加后减小的变化,高风险区和较高风险区面积先增加后减少,低风险区、较低风险区和中等风险区面积先减少后增加;②三期景观生态风险全局自相关莫兰指数分别为0.512 5、 0.555 2和0.605 5,表现为较强的正相关,土地生态风险呈聚类模式的空间分布;③20年间,区域景观生态风险高-高聚集、低-低聚集分布区域并未发生较大变化,但逐渐表现为较分散的分布;④三期景观生态风险空间相关性主要受结构性因素影响,且影响程度逐渐加深.

Landscape ecological risk assessment of Harbin section of Songhua River basin

In this paper, the landscape ecological risk index was firstly constructed by combining the landscape vulnerability index and the proportion of landscape type area with the weight assignment method of analytic hierarchy process. Taking the Songhua River Basin (Harbin Section) as the research area, on the basis of completing the three stages of landscape type extraction of the research area in 1995, 2005 and 2015, the research area was divided into 4000-meter and 6000-meter grids, and the grid landscape ecological risk index was calculated. Quantitative methods such as cold hot spot and spatial variation function were used to study the spatial-temporal variation characteristics and spatial autocorrelation of landscape ecological risk in Songhua River Basin (Harbin Section). The results showed that: (1) from 1995 to 2015, the landscape ecological risk of Songhua River Basin (Harbin Section) increased first and then decreased; the area of high-risk area and high-risk area increased first and then decreased; the area of low-risk area, low-risk area and medium-risk area decreased first and then increased; (2) from 1995 to 2015, the global autocorrelation Moran index of land ecological risk in the study area was 0.5125, 0.5552 and 0.6055 respectively;(3) from 1995 to 2015, the high-high-aggregation and low-low-aggregation areas of ecological risk in the study area did not change significantly, but gradually showed a more dispersed distribution;(4)the spatial correlation of landscape ecological risk in the study area was mainly affected by Structural factors ,and the impact of structural factors on landscape ecological risk is deepened.