Abstract: With the support of GIS and statistical analysis method, six landscape metrics reflecting the land use spatial structure were selected to build and calculate the ecological risk of Yunnan Province and its 16 prefectures using land use/cover maps of 100 m×100 m grid in 1980s, 1990, 2000 and 2005. The spatial and temporal variations of ecological risk was mapped and analyzed. Results showed that 1) The ecological risk of Yunnan Province was in the medium level with high risk in the northeast and southwest and low risk in the northwest and southeast from the view of spatial distribution; during the study periods, Diqing, Nujiang, Lijiang, Dali, Kunming, Yuxi, and Wenshan were all at a low risk level, while Lincang, Zhaotong and Qujing were in high risk areas. 2) The distribution of each prefecture’s ecological risk did not change obviously in 2005, compared with that in the 1980s. Most prefectures’ ecological risk level stayed the same level. 3) The ecological risk of each prefecture presented a trend of increasing in 1980s?1990 and 1990?2000. However, most prefectures experienced risk decrease in 2000?2005. 4) From 1980s to 2005, more than eighty percent of prefectures’ the ecological risk remained at their original level. The results can provide a scientific basis for ecological construction and regional ecological planning.

Key words: land use, spatial structure, landscape metrics, ecological risk, dynamic change

摘要： 利用1980s, 1990, 2000及2005年4期100 m×100 m土地利用栅格数据, 在GIS的支持下, 利用地统计分析方法, 基于6种反映土地利用/覆被空间结构的景观指数, 构建生态风险指数并进行空间制图, 分析云南省及其16个市(州)生态风险的时空变化。结果表明: 1) 云南省整体生态风险处于中等水平, 空间上呈西北及 东南低、东北及西南高的格局, 迪庆、怒江、丽江、大理、昆明、玉溪和文山生态风险一直较低, 临沧、昭通和曲靖一直处于高风险区; 2) 与1980s相比, 2005年各市(州)生态风险水平分布变化不明显, 大部分市(州)生态风险等级保持不变; 3) 在3个评价时段内, 1980s?1990年和1990?2000年各市(州)生态风险呈增加趋势, 2000?2005年绝大多数市(州)生态风险有所下降; 4) 1980s?2005年间, 81.25%的市(州)生态风险维持在同一等级。研究结果可为该区域的生态规划和生态建设提供科学参考。

关键词: 土地利用, 空间结构, 景观指数, 生态风险, 动态变化