近35年科尔沁沙地生态系统健康诊断研究——以巴林右旗为例

Studies on Diagnosis of Ecosystem Health Nearly 35 Years in Horqin Sandy land——A Case Study in Balinyouqi

干旱区沙地生态系统健康状况不仅决定其所提供生态服务大小,也决定着区域生态安全等级。因此,开展生态系统健康诊断,对摸清生态系统本底值,进而提高生态修复效率具有重要意义。以科尔沁沙地源头巴林右旗为研究对象,运用PSR模型构建生态系统健康诊断指标体系,将熵权法与综合评价法有机结合,确定了研究区生态系统健康指标权重和综合健康状况,并对研究区生态系统健康进行了分级诊断。结果显示:所选指标中围封草场面积的覆盖率熵权值Wj=0.0655为最大值,表明围封草场面积是影响沙地生态系统健康的最主要指标。还发现近35a中有32a科尔沁沙地处于生态系统亚健康状态,1982年、2009年、2010年处于不健康状态。这主要在于生态系统健康和状态指标呈正相关,人类活动可以辅助生态系统健康状态的恢复,同时,过度干扰生态系统的结构状态将影响生态系统的健康状况。

The health condition of arid sandy ecosystem determines not only the size of the ecological services they provide,but also the level of regional ecological security.Therefore,carrying out ecosystem health diagnosis is of great importance to the background value of ecosystem and to the increase of ecological restoration efficiency.We took Balinyouqi of Horqin Sandy Land as research site,used PSR model to construct the index system of ecosystem health diagnosis,and determine the ecosystem health index and overall health condition of the study area with the combination of entropy method and comprehensive evaluation method.And we also diagnosed the ecosystem health of the study area at different levels.The results show that the coverage rate of the enclosed grassland area in the selected index reaches to a maximum（0.065 5）,indicating that the area of enclosed pasture is the main indicator influencing the health of sandy ecosystem.It also finds that in the recent 35 years,the ecological system of Horqin Sandy Land has been in the sub-healthy state for32 years and was in unhealthy state in 1982,2009 and 2010,which results from that the ecosystem health and state indexes are positively correlated.Human activities can assist the recovery of ecosystem health while excessive interference of ecosystem structure will affect the ecosystem health.