Change Of Grain Yield And Its Influencing Factors In Anhui Province Based On LMDI Model

Food security has become the focus of attention in various countries and regions and a hot topic of scholars'research.After world war II,the world population continued to grow rapidly,and the rapid progress of industrialization and and urbanization led to the continuous reduction and degradation of cultivated land.In addition,global warming and global extreme weather events further aggravated the global imbalance between food supply and demand.China is a country with a large population,food security is not only related to People's Daily life,but also related to national economic development,social stability and national security.In recent years,although China's grain output has been increasing year by year,the self-sufficiency rate of grain has decreased due to the substantial increase in demand,especially the rapid increase in the demand for feed grain and industrial grain.Ensuring that the rice bowl of the Chinese people is firmly in their own hands is an important strategy for agricultural development in the future.It is of great significance for adjusting agricultural policies and maintaining and enhancing grain production capacity to identify the main contributing factors and their contributing degrees to the increase of grain output in China.As one of China's 13 major grain producing provinces,Anhui province is also one of the key regions identified in the national plan for increasing grain production capacity by 50 billion kilograms(2009-2020)and plays an important role in ensuring China's food security.With the advance of the rising strategy of the middle part of China,Anhui province is making great efforts to build the urban belt of the Anhui river.With the acceleration of industrialization,urbanization and the adjustment of agricultural industrial structure,the resource based constraint of cultivated land change on food production is increasingly prominent.How to utilize the existing agricultural resources,improve the grain productivity and optimize the crop planting structure and spatial distribution is of great significance to the agricultural development of Anhui province.This paper consists of five chapters.The first chapter is the introduction,which briefly introduces the research background,research significance,research status,main research methods and technical routes.The second chapter is related concepts and theoretical basis;Chapter three introduces the natural characteristics and agricultural regionalization of Anhui province.The fourth chapter is the main part of this paper,which describes the present situation of grain production in Anhui province and the main factors affecting grain yield increase.Chapter five is the conclusion and prospect.It makes a general conclusion and points out the deficiency of the article.The results showed that the grain yield in Anhui province increased from 2472.01×10~4t in2000 to 3417.4×10~4t in 2016,and increased by 945.39×10~4t between 16a,with an annual average growth rate of 2.39%.From the perspective of crop yield composition,the change trend of rice,wheat,corn and beans was basically consistent with the change trend of grain output,which was the main contributing factor of grain yield increase in Anhui province.On the whole,the contribution of sown area to grain yield is greater than the effect of yield per unit area,and the effect of yield per unit area on grain yield cannot be ignored.From the perspective of crops,the positive effect of sowing area of rice,wheat,corn and beans was significant.The sown area of potato and bean showed negative effect.The yield per unit area effect of rice,wheat and corn were all positive,among which the yield per unit area effect of wheat was the most significant.The yield effect of beans,tubers and grains per unit area was negative.The increase of sowing area of rice,wheat and corn with high yield per unit area is the main contributing factor to the continuous improvement of grain yield in Anhui province.The increase of grain yield is not only affected by the increase of yield per unit area of crops,but also by the compression of sowing area of high-yield crops to low-yielding crops.In terms of spatial distribution,the areas with higher accumulative effect of rice were distributed in the south of Huaihe river.Compared with the accumulative effect of sowing area,the areas with higher per unit yield effect tended to southern Anhui.The spatial distribution of sowing area effect and yield effect of wheat per unit area are basically the same,both of which are concentrated in northern Anhui province.The effect of sowing area and yield per unit area of maize showed a huge spatial difference.The areas with higher sowing area effect are mainly concentrated in northern Anhui.The areas with higher yield per unit area are mainly distributed in southern Anhui.Compared with rice,wheat and corn,beans,yams and cereals had a more significant negative effect on the total grain output in urban areas.Legumes were distributed in the north and northwest of Anhui province.The areas with higher yield per unit area are mainly concentrated in southwest and south Anhui.The negative effect of potato sowing area decreased successively from northwest to southeast,and the positive effect of yield per unit area was mainly found in central Anhui.The effects of grain sown area and yield per unit area were not significant.From the county scale,Anhui county grain production is increasingly concentrated in large counties.The areas with negative grain sowing area effect in counties are relatively scattered,and relatively few are distributed in northern Anhui,while the relatively concentrated areas are mainly in the mountainous areas of southern Anhui.The effect of grain yield per unit area is relatively concentrated in the spatial distribution of counties.The negative effect of grain yield per unit area is mainly distributed in the areas along the Yangtze river plain.