中国县域单元生态脆弱性时空变化研究

Spatial and temporal changes of ecological vulnerability per county unit in China

以中国2853个县(市、旗、区)为研究单元,以1980、1990、2000和2010年全国1 km格网土地利用数据和中国县级行政单元社会经济统计数据为基础,通过VSD模型,构建了基于自然和人为共同作用下的生态系统影响力指数和社会经济适应力指数,用以综合表达生态脆弱性空间分异,在此基础上对中国县域单元的生态脆弱性进行定量评价.结果表明:中国县域生态系统影响力指数持续降低,2000年之前呈现由"东北到西南"逐渐降低的趋势,2000年之后,基本呈现"中东部及新疆北部高、西南低"的格局.适应力指数空间分布差异十分明显,表现出东南沿海高于中部,中部又高于西部的格局.从生态系统脆弱性空间分布格局来看,东南部比西部地区更脆弱,从时间变化来看,中国生态脆弱度整体好转,局部恶化;从数量变化来看,1983个县域单元处于高度脆弱区和极度脆弱区,仅有327个县域单元于处于轻度和微度脆弱区.处于极度脆弱区和高度脆弱区的县域单元未来要合理规划土地利用,加强土地利用管理,调整用地布局并严格控制城镇规模扩张;对于轻度和微度脆弱区则应坚持以生态建设和环境保护为主,禁止污染型产业发展,有序引导人口转移,发展生态旅游业和高技术产业.

Based on the statistical data and 1 km × 1 km land use data in the year of 1980,1990,2000 and 2010 in 2853 counties and districts in China,the indexes of ecosystem impact and adaptive capacity of social economy were built through VSD model to reflect and assess spatial differentiation of ecological vulnerability comprehensively and quantitatively. The results showed that the impact index of ecosystem decreased consistently. Before 2000,it decreased from northeast to southwest,while it was higher in mid-eastern and northern Xinjiang province than southwestern after 2000. In addition,adaptive capacity index showed a significant spatial variation,with higher in the southeastern,lower in central,while the lowest in the western. The ecological system was more vulnerable in mid-eastern than western counties and districts. The overall ecological vulnerability improved in most counties and districts. 1983 counties and districts were in the highly and extremely vulnerable zones from 1980 to 2010,while 327 counties and districts were in the mild and little mild vulnerable area. Reasonable land use planning and management,adjustment of land use pattern and control of urban expansion should be taken into consideration in extremely and highly vulnerable zones. Attention should paid on protection of ecological environment,relocation of crowded industry and population,promotion of ecotourism and high technology industry,and banning of polluting industries in the mild and light vulnerability zones.