浙江省土地利用格局时空变化及生态风险评价

基于1990~2015年浙江省6期的土地利用数据，分析土地利用的时空变化，构建生态风险指数，对不同时期的浙江省土地利用生态风险进行了评价。结果表明：（1）浙江省土地利用变化表现为耕地大量减少而建设用地剧增；土地利用转移方向主要为耕地、林地、水域向建设用地转移；其中以2000~20005年和2010~2015年土地利用动态度最高；（2）浙江省生态环境质量下降。中生态风险区是区域的主导类型，较高、高生态风险区向外扩张，高值区主要分布在杭州湾附近，沿海区域，杭州西南部、衢州和金华三市接壤区域。低等级生态风险区分布在相邻高等级生态风险区的周围，大致成圈层状向外扩散;（3）土地利用生态风险等级转换差异较大。生态风险转移主要是由低向高等级转换，且其生态风险等级年均转换速率呈上升趋势，生态风险转换主要发生在城市、沿海区域如杭州湾附近、温州、台州沿海等经济发展活跃的地区;（4）浙江省各地级市生态风险值时空分异较大。各市生态风险值主要呈上升趋势，宁波市生态风险变化最大，衢州市变化最小。空间分布上，杭州市生态风险值最高，远大于其他地级市，舟山市生态风险值最低。

Spatial and Temporal Changes of Land Use Pattern and Ecological Risk Assessment in Zhejiang Province

Based on the land use data of the 6th period of Zhejiang Province from 1990 to 2015, the temporal and spatial changes of land use are analyzed, and the ecological risk index is constructed to evaluate the ecological risk of land use in Zhejiang Province in different periods. The results show that: (1) The land use change in Zhejiang Province is characterized by a large reduction in arable land and a sharp increase in construction land; the direction of land use transfer is mainly the transfer of cultivated land, forest land, and water areas to construction land; of which, the land use dynamic degree is the highest from 2000 to 20005 and from 2010 to 2015; (2) The quality of ecological environment in Zhejiang Province has declined. the moderate ecological risk area is the dominant type of area, and the high and the extremely high ecological risk areas expand outward. The high value areas are mainly distributed in the vicinity of Hangzhou Bay, the coastal area, and the areas bordering the southwest of Hangzhou, Quzhou and Jinhua. The low-grade ecological risk areas are distributed around the adjacent high-level ecological risk areas and generally spread out in a circular pattern. (3) Land use ecological risk grade conversion varies greatly. The ecological risk shift is mainly from low to high level, and the annual average conversion rate of its ecological risk level is on the rise. Ecological risk conversion mainly occurs in cities and coastal areas such as Hangzhou Bay, Wenzhou, and Taizhou coastal areas where economic development is active. (4) The ecological risk values in the cities of different levels in Zhejiang Province differ greatly in time and space. The city’s ecological risk values mainly show an upward trend, Ningbo’s ecological risk changes the most, and Quzhou City has the smallest change. In terms of spatial distribution, Hangzhou has the highest ecological risk value, which is much higher than other prefecture-level cities. Zhoushan has the lowest ecological risk value.