Study On Cultivated Land Development Intensity Change And Suitability Evaluation In Hunan Province

As the bearing parent of grain production,cultivated land provides the space environment for grain breeding.Whether its development and utilization is appropriate is the focus of attention to ensure China’s food security.In recent years,the shortage of cultivated land area and the problem of environmental restriction become more and more acute,and the replacement of artificial capital by Natural capital has become the main factor restricting the sustainable development of cultivated land,which has become an obstacle to the development and utilization of cultivated land.The development intensity of cultivated land in different regions with different qualifications has different moderate range,which can not only ensure the effective supply of grain,but also maintain the sustainable production capacity of cultivated land.Taking Hunan Province as the main research area,based on the double evaluation system of resource carrying capacity and socio-economic development level,this paper comprehensively measures the spatio-temporal moderate differences of cultivated land development intensity in Hunan Province and analyzes the main active factors resulting in the differences,it can provide reference for the moderate regulation and control of cultivated land development intensity in Hunan Province and all over the country.Firstly,the spatial and temporal variation of cultivated land development intensity in Hunan Province from 1999 to 2017 was explored by using natural break point method and relative change rate method.The results show that:(1)the overall distribution of cultivated land development intensity in Hunan Province is characterized by“High in the middle north and low in the southwest”,which is mainly affected by the topographic gradient and the distribution of water resources in the natural environment,zhangjiajie,Huaihua and Xiangxi Tujia and Miao Autonomous Prefecture are potential areas in the balance of cultivated land development.(2)from 2004 to 2013,Hunan Province mainly benefited from the agricultural policy,which showed the increase period of cultivated land development intensity,and from2014 to 2017,the decrease period of cultivated land development intensity.(3)from the characteristics of temporal and spatial distribution and temporal sequence change,it can be concluded that the width,frequency and depth of cultivated land development lay their primary foundation,tap their natural potential and dominate their temporal and spatial flow respectively.Next,the appropriate range and spatial matching of cultivated land development intensity in Hunan Province are explored.The results show that:(1)52% of counties in Hunan province are of moderate type,26% are of transitional type,and 22% are of low type.(2)in the spatial distribution of cultivated land development intensity in Hunan Province,there is a long-term feature of “East High West low moderate degree”.(3)the moderate level of cultivated land development intensity generally shows the trend of “Regional equilibrium”,but the wuling mountainous area in northwest Hunan is the stable low degree gathering area,and the northern Dongting Lake area is the stable over-gathering area.4.In the integration analysis,it is found that the cultivated land development intensity of Hunan Province tends to “Moderate-excessive”marginal zone,which can be divided into moderate maintenance area,low development area and over-regulation area.The moderate level of cultivated land development intensity at the level of economic sector mostly presents “ Steady-state synchronous fluctuation”.From the estimation of cultivated land development intensity in Hunan Province,it is found that the structure decomposition of cultivated land development intensity should be guided in order to improve the cultivated land development intensity in different regions,the sustainable development of regional cultivated land can be more scientifically implemented.In the process of judging the moderate degree of cultivated land development intensity in Hunan Province,we found that the cultivated land development intensity in Hunan Province is facing the problem of over-development.The main problem is the regional difference of cultivated land development intensity caused by the development inertia,the regional matching of cultivated land development intensity in Hunan Province can be realized by adjusting the scale of economic sector.In general,the intensity and moderation of cultivated land development in Hunan province are mainly controlled by three major factors: long-term natural factors,short-term social and economic factors,and development inertia factors,the city areas of Hunan Province are divided into potential areas,over-development areas and moderate stability areas,and the structural characteristics of cultivated land development intensity in each area are regulated in an orderly manner,first,the cultivated land development breadth should be enough to meet the demand of moderate improvement of cultivated land development intensity,then the cultivated land development frequency should be controlled scientifically and reasonably,finally,the cultivated land development depth should be explored continuously and comprehensively.In addition,the research plan on the moderate regulation of cultivated land development intensity needs to establish multi-level research targets and objects,and plan the research effect expectation of different periods,in order to achieve the appropriate intensity of cultivated land development zoning optimization control purposes.