关键词: 土地利用, 空间结构, 景观指数, 生态风险, 动态变化

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