泾河流域土地利用变化驱动力及其政策的影响

Land-Use Change Dynamics, Driving Forces and Policy Implications in Jinghe Watershed of Western China

本文对泾河流域土地利用变化驱动力及其土地利用政策的影响进行了深入的探讨。泾河流域属于中国西北偏僻山区,是西北干旱地区和中部半干旱地区的过渡带,也是下游灌溉水资源的重要发源地。本研究从泾河流域选取了3个县作为研究区域,并利用地理信息系统和遥感影像技术对该区土地利用变化的驱动力进行考查;调查问卷用于调查影响土地利用变化的因素;转移矩阵和SPSS统计分析软件用于定量分析1980至2003年间土地利用的变化情况;加权平均指数分析方法用于对当地农民的认知情况进行排序。结果表明,林地和草地变幅较大;农地、草地和林地之间的变化交替发生;农业政策、市场需求、个人意愿以及环境保护则是引起这些变化的最重要的驱动力。因此,本研究认为,为了更全面地理解土地利用方式的变化,社会经济因素应给予充分考虑。政府政策和试图影响农民土地利用活动的农业环境项目在适合当地条件的情况下,其获得成功的可能性较大。但是,这些政策和项目必须在非常具体的计划和实施的条件下才能获得成功。

This paper provides an insight into the land-use changes, driving forces and policy implications in the upstream of the Jinghe watershed, a remote mountainous and human dominated rural landscape in northwestern China, and a land link and detour between arid marginal regions of the northwestern part and those of the semi-arid middle part of the country, and an important irrigation water source for the down streams. Three representative counties were selected for the study. Spatial and temporal GIS database interpreted from Remote Sensing Imagery were used to investigate the dynamics of land-use change. A structured questionnaire survey was conducted to investigate factors affecting land-use changes. A transition matrix and SPSS software was used to make quantitative comparisons of the land-use changes between discrete time periods extending from 1980 to 2003, and farmers’ perceptions were analyzed by construction of weighted index. The results show that wooded and pastures land was the predominant land-use change; a continuing ‘exchange’ of land area occurs between agricultural land-use and grass and wooded categories that could improve the long-term ecological and economic condition of the area. Agricultural policies, market demand, and personal willingness are the prioritized driving forces causing such changes. It is highlighted from this study that socio-economic factors must be taken into consideration to fully understand patterns of land use change in human-dominated landscape. Governmental policies and agri-environmental programs aiming at influencing farmers’ land-use activities have a higher chance of success if they are adapted to local conditions, but they should be planned and implemented on a more concrete and specific level.