Study On The Spatial Correlation Of Cultivated Land Quality And Landscape Pattern

Since 21st Century,along with the accelerating process of urbanization and industrialization in China,the problem of food security is becoming more and more serious due to the serious degradation of cultivated land,the shortage of water resources and the increasingly harsh climate.At the same time,the composition and spatial pattern of cultivated land landscape have changed greatly.There are a series of problems such as the deterioration of land ecological environment,the aggravation of land pollution load and the decline of land quality.The shortage of cultivated land resources and the problem of cultivated land ecological security are becoming increasingly prominent.The previous evaluation of cultivated land quality did not involve the ecological security function of cultivated land,lead to the fact the quality of cultivated land has not been fully explained.This paper tries to evaluate the quality of cultivated land from the angle of multifunction of cultivated land,and by finding the coupling relationship between the quality of cultivated land and the landscape spatial pattern of cultivated land,provides a theoretical reference and realistic reference for the quality grading and evaluation of cultivated land,the optimization of cropland compensation pattern and the trinity protection of quantity,quality as well as ecology of cultivated land,so as to ensure national food security and cultivated land ecological safety.Firstly,based on the theory of cultivated land multifunction,the connotation of cultivated land quality is defined,with the evaluation index system of cultivated land quality is constructed,then the multilevel and deep level evaluation of cultivated land in the study area is carried out.Secondly,the characteristics of the quality distribution of cultivated land under the influence of geographical factors such as altitude,road,river and village are analyzed,following the landscape pattern index of cultivated land under the influence of different geographical factors is calculated,to analyzed the characteristics of the landscape spatial pattern change of cultivated land.After that,the spatial autocorrelation analysis of cultivated land quality and cultivated land landscape pattern index was conducted from village scale.Finally,the geographically weighted regression model is applied to analyze the correlation between cultivated land quality and cultivated land landscape pattern index at village level,in order to explore the coupling between cultivated land quality and cultivated land landscape pattern.The main results are as follows:(1)Along with the elevation of elevation,the distance from rivers,roads and villages increased,and the quality of cultivated land decreased.There was a trend of decreasing dominance degree,increasing fragmentation degree and decreasing aggregation degree of cultivated landscape pattern;(2)The quality of cultivated land and cultivated land landscape pattern index itself has a certain degree of global positive correlation,while the quality of cultivated land,PLAND,LPI,MNN and IJI showed a more obvious phenomenon of agglomeration;(3)The quality of cultivated land and PD,PLAND,LPI,MNN,IJI are higher degree of spatial correlation,and the correlation coefficient is higher area for the poor quality of cultivated land area;(4)There is a certain degree of coupling between cultivated land quality and landscape pattern index.On the one hand,it is feasible to identify the quality level of cultivated land by landscape pattern index,especially for identifying cultivated land with poor quality.On the other hand,it indicates that adjusting and changing the spatial pattern characteristics of cultivated land has positive effect on improving the quality of cultivated land.Therefore,it is of great practical significance to introduce the landscape pattern analysis of cultivated land to the assessment of the quality of cultivated land,the balance of cultivated land,and the compilation of land renovation planning.