喀斯特地区土地利用变化的生态服务功能价值响应

Economic Response of Ecosystem Service Functions to Landuse Changes in Karst Region

以地处喀斯特石山区的广西省河池市为例,以研究区单位面积农田生态系统在1988,1998和2003年提供的食物生产服务经济价值为基础,对研究区生态服务功能价值进行估算,并对照3个年份土地利用变化与生态服务功能价值的变化,找出了不同时段土地利用结构变化所引起的生态服务功能价值响应与变化特征。研究结果表明,1988—2003年河池市土地利用变化产生了较大的生态响应,生态服务功能价值总体上呈增长趋势;1988—1998年除了农田生态系统服务功能价值增长仅14.6%外,其它各类生态系统增幅都在25.9%以上;1998—2003年增幅明显减趋缓,草地生态服务功能价值则呈现急剧下滑状态,变化特征基本上与土地利用变化一致。河池市土地利用方式还需要进一步改善,尤其对面积广大的未利用地的生态改造和石漠化地区的生态恢复将会带来更大的生态效益。

By taking Hechi City of Guangxi Province in karst mountainous region as an example, the economic value of ecosystem service functions was estimated. The economic values of food production per hectare of cropland ecosystem in 1988, 1998, and 2003 were used as a base of the study. Then the economic values in the three years were contrasted with the landuse situations in corresponding years so as to find out the features of economic value changes of ecosystem service functions induced by landuse changes in different periods. Results showed that during the years from 1988 to 2003, the ecological responses to landuse changes were obvious. Economic values of ecosystem service functions were improved in general. From 1988 to 1998, except the 14.6% increment of economic value for farmland ecosystem, the increments of economic value for other ecosystems were all above 25.9%, while from 1998 to 2003, the increments became slow evidently and negative economic value for grassland ecosystem even appeared. Landuse changes were almost accordant with the changes in ecosystem economic value. These facts prove that the local landuse manner needs to be reformed. Especially, reconstruction of wider unused land and ecological restoration of stony desertification land may bring very significant ecological benefits.