基于典型村落的山—坝系统土地利用演化时空分异特征OA北大核心CSTPCD

As a typical eco-vulnerable area of rocky desertification in karst mountains of Southwest China,Guizhou Province is characterized by a large number of mountains and hills,and a scarcity of basin land and high-quality cultivated land.Consequently,the contradiction between large human need and small farmland acreage is increasingly prominent.In this study,we selected three typical villages-Shuiyuan village,Manyu village and Haohuahong village in Haohuahong town,Huishui county,Guizhou Province as the study areas.Shuiyuan village is located in a remote mountainous area with a large number of barren sloping farmlands.This village is mainly developing the agricultural economy.Manyu village is a typical of low hills and gentle slopes,distributed with both sloping farmlands and basin land.This village is mainly developing the breeding industry.Haohuahong village is characterized by the flat terrain,with rich farmland resources and high degree of agricultural mechanization,and it is a typical model village of modern agricultural development in Huishui county.These three villages have jointly formed a mountain-basin system. On the basis of the regional characteristics of mountain-basin system,we explored the spatial-temporal differentiation characteristics of the coupling evolution of rural population,farmland and homestead in these three villages from 1990 to 2018. We acquired the data of depopulation,farmland and rural homestead in these three villages by participatory rural appraisal,analyzed the spatial-temporal evolution of population,farmland and homestead from the village gradient perspective,and further divided the functions of farmland and rural homestead.The results show as follows:(1)The degree of rural depopulation is different.Population outflows are severe in mountainous areas with marked depopulation.There are less population outflows in basin areas,with depopulation.Population outflows are very common with prominent depopulation in the intersected areas between mountains and basins.(2)Regional differences of farmland abandonment are obvious.Farmland abandonment is the most severe in mountain areas,followed by the areas intersected between mountains and basins,and farmland abandonment in basin areas was less severe.Abandonment or transformation of farmland has caused the changes of utilization types and functions of the farmland.(3)From the perspective of homestead use,the number of homesteads increased and the space of homestead expanded to outside but was deserted inside.Structures and functions of homestead changed noticeably.(4)Rural depopulation drove the change of land use,which was mainly driven by socio-economic change and regional population migration from rural to urban areas.Various factors affecting the changes of land use and the processes of these changes are interdependent and restrict each other,which has constituted a dynamic coupling phenomenon. To sum up,the spatial-temporal variation characteristics of land use evolution in mountain areas,intersected areas between mountains and basins and basin areas are different in different periods.The research results are helpful to guide the rural farmland utilization and protection,homestead activation and utilization in mountain-basin systems with different geographical conditions,socio-economic development levels,traffic conditions and geological backgrounds in Guizhou Province.It is of reference value for us to realize the sustainable development of society and economy in terms of mountain-basin system.