基于土地利用变化的桂林市区生态风险评价

Ecological risk assessment for Guilin urban district based on land use change

基于桂林市区1986和2006年TM影像,提取2个时相土地利用类型数据,构建综合生态风险指数;通过系统采样和普通克吕格插值,编制生态风险空间分布图,定量评价桂林市区生态风险的时空变化特征。结果表明:20年间,桂林市区生态风险整体呈上升趋势,高及较高生态风险区范围不断扩大,较低和中生态风险区域持续减少;生态风险的空间差异显著,整体呈北高南低、中间高四周低,高风险区由零散分布趋向于集中连片分布的格局特点;林地、草地和水域分布的区域以低生态风险和较低生态风险为主,耕地以中生态风险为主,建设用地以较高生态风险和高生态风险为主,其中林地的生态风险等级最低。研究结果可为桂林市区环境管理和生态风险决策提供科学参考。

Based on TM image data of Guilin city urban districts taken in 1986 and 2006, the land use data of Guilin city in each year were extracted, an ecological risk index was constructed; the distribution map of spatial distribution of ecological risk was gained by system sampling and general Adalbert Krueger interpolation, thus the ecological risk characteristics of temporal and spatial changes in Guilin city urban districts were quantitatively evaluated. The results show that the total ecological risk in Guilin city increased in past 20 years,othe areas of extremely high and high ecological risk were expanding, while the areas of low and moderate ecological risk were decreasing; the spatial differences of ecological risk was significant, ~ ecological risk was higher in the north and lower in the south, and higher in middle area than in peripheral area, and the distribution of high ecological risk tended to be centralized from scattered distribution; the majority of the woodland, grassland and water body belonged to the extremely low and low ecological risk areas and the cropland belonged to moderate ecological risk areas, whereas the construction land belonged to the high and extremely high ecological risk areas; the level of ecological risk of woodland was the lowest among land use types. The results can provide scientific references for environmental management and ecological risk decision-making of Guilin city.