A Study On The Spatiotemporal Correlation Between Intensification And Fragmentation Of Cultivated Land In Jiangsu Province

With the rapid advancement of industrialization and urbanization,cultivated land resources are facing a tense trend.In order to better promote the rationalization of land use structure,efficient land use,and protect cultivated land resources,intensive use of cultivated land is the best choice.In the process of the simultaneous advancement of social economy and the intensification of cultivated land use,the problem of cultivated land fragmentation has gradually emerged,which has brought about waste of land resources,increased production costs and hindered use of technology and modern development.Therefore,in order to maximize the social,economic and ecological benefits of cultivated land utilization,this paper uses Jiangsu Province as the research area to carry out the correlation between the intensive use of cultivated land and the fragmentation of cultivated land.This paper,the county area of Jiangsu Province was used as the research unit.Through the analysis of research status at home and abroad,the evaluation index system of cultivated land intensive use and cultivated land fragmentation were constructed respectively,and the time and space development and regional differences of the two systems were measured and analyzed.Using grey correlation and spatial autocorrelation analysis to further analyze the temporal and spatial correlation between cultivated land intensive use and cultivated land fragmentation,the main influencing factors were discussed,and countermeasures and suggestions were put forward.The main research conclusions are as follows:(1)Intensive use of cultivated land in Jiangsu Province had shown an unsteady growth.From the overall level of the province,the average projection value of intensive use of cultivated land in Jiangsu Province during the study period increased from 1.59 in 2000 to 2.12 in 2017,indicating that the level of cultivated land intensive use in Jiangsu Province had been steadily increasing in the past 20 years.In general,the level of cultivated land intensification in Jiangsu Province and the three major regions showed certain phase characteristics.The comprehensive evaluation value of the level of cultivated land intensification in the province and the three major regions from 2000 to 2017 showed that "growth is the mainstay,supplemented by phase fluctuations." This reflected that the intensive use of cultivated land in Jiangsu Province did not show a steady growth trend during this study period.(2)The fragmentation of cultivated land in Jiangsu Province was declining as a whole and increasing in some areas.From the perspective of the whole province as a whole,the degree of cultivated land fragmentation in Jiangsu Province decreased from-0.23 in 2000 to-0.28 in 2017 during the study period.The overall trend was stable and slowly declining,indicating that Jiangsu Province in the past 20 years the fragmentation of cultivated land is steadily decreasing.In general,the fragmentation of cultivated land in Jiangsu Province and the three major regions shows a certain regularity.The comprehensive evaluation value of cultivated land fragmentation in the province,southern Jiangsu and northern Jiangsu from 2000 to 2017 shows "mainly stable,with slow decreased as a supplement" reflected the fact that the cultivated land in Jiangsu Province had been fragmented during the study period and had shown a steady trend of change.It could be seen that the changes in 2000–2005 were small,2005–2015 showed a growth trend,2015–2017 showed a downward trend,and the overall trend was "steady-declining".The fragmentation of cultivated land in central Jiangsu had shown a continuous increase from 2000 to 2017,but the comprehensive evaluation value had always been at the lowest level.(3)The temporal and spatial correlation between intensive use of cultivated land and the fragmentation of cultivated land in Jiangsu Province had continued to increase.1)From the gray correlation analysis of cultivated land intensive use and cultivated land fragmentation,it could be seen that the correlation between cultivated land intensive use and cultivated land fragmentation in Jiangsu Province was not much different.The degree of change relevance was gradually increasing.The analysis showed that the distribution index was the main factor that affects the intensive use of cultivated land,and the output benefit was the main factor that affects the fragmentation of cultivated land.2)From the results of the bivariate global spatial autocorrelation analysis of cultivated land intensive use and cultivated land fragmentation,it could be seen that there were significant positive and negative spatial correlations between the both,and there was a positive spatial correlation in 2010 and 2015,2017 showed a negative spatial correlation.It showed that the intensive use of cultivated land and the fragmentation of cultivated land in the counties and cities of Jiangsu Province in these three periods were not randomly distributed in space,but had a certain degree of dispersion or aggregation.3)From the results of the bivariate local spatial autocorrelation analysis of the intensive use of cultivated land and the fragmentation of cultivated land,it could be seen that with the continuous enhancement of the bivariate spatial correlation,the significant concentration of LISA continued to increase from2000 to 2017.The H-H clusters are mainly distributed in northern Jiangsu,indicating that the intensive use of cultivated land and the level of finely fragmented cultivated land in some counties in northern Jiangsu during this time period are at a high level.The L-L agglomeration area was mainly located in the junction area between central Jiangsu and southern Jiangsu.The L-H agglomeration area was more distributed and showed a trend of increasing distribution every year,mainly in the northern Jiangsu area.The distribution of H-L clusters was less concentrated in southern Jiangsu,where the level of fragmentation of cultivated land was higher due to topographical conditions.The research showed that the development trend of intensive use of cultivated land in Jiangsu Province is increasing,and the change trend of cultivated land fragmentation was not significant.The correlation between the both was gradually strengthened,indicating that the degree of mutual influence between cultivated land intensive use and cultivated land fragmentation continues to deepen.In order to promote the rational use of cultivated land in Jiangsu Province,attention should be paid to improving the level of cultivated land utilization and ensuring the efficiency of cultivated land output;promoting land consolidation and reducing land fragmentation;optimizing the structure of agricultural land and focusing on ecological development of cultivated land;promoting intensive use of cultivated land and coordinating large-scale development etc.