Research On Transformation Of Cultivated Land System Based On Dominant Form And Implicit Form

The research is carried out from the two angles of dominant and recessive forms of cultivated land.The recessive form lies in the function of cultivated land,while the dominant form lies in the spatial change.Firstly,the general situation of agricultural policies and farmers in Guizhou Province after 1978 was sorted out,and an evaluation index system of farmland function was established.Then,entropy weight method was used to calculate the index weight and its function value,and the farmland multifunction was classified and evaluated.The functions of farmland in different social and economic conditions in the whole province and various states and cities were compared,and the differences and reasons were analyzed.Secondly,through comparative analysis of typical research areas,using ARCGis,ENVI,Fragstas4.2 and other software to divide land use types,calculate transfer matrix,dynamic attitude and other indicators,landscape pattern index and other methods,comparative analysis of the impact mechanism of cultivated land transformation under different economic conditions of different landforms in Guizhou Province,the research shows that:(1)The function of cultivated land in Guizhou Province is on a downward trend.The function transformation started around 2006.There are certain differences among different states and cities.The regions with faster economic development have been transformed ahead of schedule around 2004,while the regions with slower economic development will be transformed around 2012.There are differences in spatial distribution of cultivated land functions,which are mainly related to the combination of regional cultivated land pressure and economic development degree.The cultivated land function value with low cultivated land pressure and high GDP(such as Zunyi and Liupanshui)is the highest,followed by high cultivated land pressure and high GDP(such as Guiyang City),followed by high cultivated land pressure and low GDP(such as Anshun and other regions),and the low cultivated land pressure and low GDP(such as Qiannan and other regions)are the lowest.(2)The spatial change of cultivated land in the study area is the most severe from 2010 to 2016.The cultivated land in Ba district and county is shrinking,and the transfer direction is mainly to residential areas,construction land and garden plots,as well as a small amount of abandoned land for grassland irrigation.The cultivated land in mountainous counties has obviously expanded,mainly from irrigated grassland and woodland.Cultivated land in mountainous areas is also mainly used for residential areas and construction.The guiding mechanism of cultivated land layout gives priority to dam land resources,followed by mountain valleys.When there is no good terrain resources,market economy factors are dominant,and cities and towns are the center to expand from the periphery to the periphery.(3)The recessive form transformation in the study area is greatly influenced by social and economic conditions and capital conditions,while the dominant form transformation is greatly influenced by cultivated land conditions,topography and location conditions.(4)The recessive form of cultivated land is a sufficient and unnecessary condition for the dominant form.When the recessive form(function)remains unchanged,the dominant form(form)will remain unchanged,while when the recessive function changes,the dominant form may remain unchanged.The combination of explicit and implicit changes determines the intensity of cultivated land transformation.