Evaluation Of Arable Land Fragmentation In Typical Areas Of Different Landform Types In Guizhou Province And Study Of The Driving Factors

Food security is a solid foundation for the stable operation of the social economy and an important guarantee for the long-term security of the country.At present,in the face of the new epidemic and international conflicts and the frequent occurrence of extreme weather,it is of great importance to effectively stabilise food production and guarantee national food security.Arable land is the core form of land use,the fundamental guarantee of national food security,and the land resource most closely related to human survival and development.In the Karst region of southwest China,the special topography makes the concentration of arable land low,agricultural mechanisation is hindered,the use of arable land is inefficient,and the reserve resources are poor,so arable land has become the most valuable resource.Arable land has become the most precious resource.With the continuous development of society,people’s demand for land is increasing,while arable land resources are decreasing,and the phenomenon of fragmentation of arable land is serious.The fragmentation of arable land has led to the division of arable land into plots,increasing the cost of farming,low prices per unit of food crops and low productivity,leading to a large-scale increase in the cultivation of cash crops,which has had many negative effects.The fragmentation of arable land has greatly contributed to the non-food and nonagriculturalisation of arable land and has seriously affected national food security.How to reconcile the contradiction between the growth of food demand and resource and environmental constraints,and how to scientifically adapt the fragmentation of arable land to make it beneficial to the sustainable and intensive use of arable land and compatible with the environmental context is the goal of long-term research and practice on the management of fragmentation.Guizhou is a province rich in landscape types and well-known for its mountainous tourism,but along with the complex topography,fragile ecological environment and inefficient use of arable land resources,the fragmentation of arable land is serious.In order to understand the current situation and degree of fragmentation of arable land in different landscape types in Guizhou Province,an evaluation index system for fragmentation of arable land is constructed from three levels: spatial form,ownership status and accessibility of arable land,and a comprehensive evaluation method is used to comprehensively evaluate the fragmentation of arable land in typical areas of different landscapes in Guizhou Province.The driving factors of arable land fragmentation were also studied using a geographic probe.The main research findings are:(1)The amount of fragmentation of cultivated land spatial form varies greatly in different degrees.The degree of fragmentation of cultivated land spatial form varies among different geomorphic types,and the polarization is serious.The spatial fragmentation of cultivated land in different landforms is generally shown as follows: peak cluster depression>non-karst>karst trough>karst basin>karst plateau>karst valley,and the spatial fragmentation of cultivated land in different degrees is generally shown as: moderate>severe>mild;The spatial fragmentation of cultivated land in the study area shows that the north is lower than the south,and the west is lower than the east.(2)There are obvious differences in the number of farmland ownership fragmentation in different degrees,and the degree of ownership fragmentation is relatively high among different geomorphic types.The overall performance of cultivated land ownership fragmentation in different geomorphic types is as follows: karst canyon>karst plateau>karst trough>karst basin>peak cluster depression>non-karst,and the overall performance of cultivated land ownership fragmentation in different degrees is as follows:severe>moderate>mild;The fragmentation of cultivated land ownership in the study area shows that the north is higher than the south,and there is little difference between the east and the west.(3)There is no significant difference in the amount of fragmentation of the accessibility of cultivated land in different degrees,but there is a significant difference in the degree of fragmentation between different geomorphic types.The overall performance of arable land use accessibility fragmentation in different geomorphic types is as follows: non-karst>peak-cluster depression>karst basin>karst trough>karst plateau>karst valley,and the overall performance of arable land use accessibility fragmentation in different degrees is as follows:moderate>mild>severe;The fragmentation of arable land use accessibility in the study area shows that the north is lower than the south,and the difference between east and west is not obvious.(4)The cold spot area of karst canyon and karst plateau area is large,the characteristics of fine fragmentation and accumulation of cultivated land in karst valley and karst basin are not significant,and the peak cluster depression and non-karst area extremely hot spot area are large.Karst canyon area mainly shows extreme cold point and cold point,and the insignificant area is large.(5)The leading driving factors of farmland fragmentation in different geomorphic types are different.The leading influencing factors of farmland fragmentation in karst plateau and karst valley areas are the distance from rural roads,the leading influencing factors of farmland fragmentation in non-karst,karst valley and karst basin areas are the distance from rural homestead,and the leading influencing factors of farmland fragmentation in peak cluster depression areas are elevation.(6)The formation of cultivated land fragmentation is affected by many factors.The same factors have different effects on farmland fragmentation among different geomorphic types,and the interaction between various types of factors has different degrees of enhancement compared with the single factor of farmland fragmentation.