采用基于决策树的分层分类与监督分类相结合的方法,提取关中地区1990年2、000年和2007年土地覆盖信息,并运用生态经济学方法构建研究区3期生态服务价值空间格局。结果表明,3期生态系统服务总价值分别为557.39亿元、507.29亿元和533.77亿元。1990—1998年,由于林地、草地局部破坏严重,区域生态服务功能总价值大幅缩减;1999年之后,随着退耕还林还草及配套政策的落实,区域生态有所好转,尤其是2000年之后,生态服务总价明显回升,但就现状而言,依然不容乐观。3期的生态经济承载指数分别为0.436 9、2.678 4和6.430 2,土地生态压力在逐年增大。加强渭河平原区的耕地保护,稳定和推进渭北高原和秦岭—关山区的生态恢复和建设成果,是未来关中地区土地利用管理中的重要环节。
The exploration and calculation of the eco-environment response to LUCC in Guanzhong area constitute the basis for the study and application of ecological compensation and for the realization of regional sustainable development.In this paper,the method for decision tree-based multi-layer information extraction and supervised classification was employed to extract the information of land cover in Guanzhong area in 1990,2000 and 2007.Then the different kinds of general service values of ecosystems in Guanzhong area in 1990,2000 and 2007 were evaluated respectively using the method of ecological economics.Some conclusions have been drawn: ① In 1990,2000 and 2007,the total service values of Guanzhong area's ecosystems were 55.739 billion yuan,50.729 billion yuan and 53.377 billion yuan respectively,which further demonstrated that the regional service values of ecosystems decreased abruptly due to local serious degradation and deterioration of forest and grass from 1990 to 1998,and were increasing significantly after 1998 due to implementation of returning cultivated farmland to grassland and forest land.② The index of ecosystem's capacity to support economy in Guanzhong area rose from 0.436 9 in 1990 to 6.430 2 in 2007,which indicated that pressure on ecosystem is increasing continuously with the development of economy,and the task of ecosystem restoration and construction remains a key link in keeping the sustainable development of regional economy.