Spatiotemporal Variation Characteristics Of Rice Production In Yangtze River Economic Belt

The Yangtze River economic belt consists of nine provinces and two municipalities including Shanghai,Jiangsu,Zhejiang,Anhui,Jiangxi,Hubei,Hunan,Chongqing,Sichuan,Guizhou and Yunnan.Its rice production is of great significance for ensuring national food security.Based on the agricultural production data from 1978 to 2016,the spatiotemporal variation of rice planting area and total production in Yangtze River economic belt in the period mentioned above were studied,meanwhile,changes of comparative advantage and production efficiency of rice production in Yangtze River economic belt from 2004 to 2016(during the period when rice area and yield resumed to increase)were studied,by classical statistics,econometrics,geographic information system and other research methods.The results showed that(1)The Yangtze River economic belt had been the largest rice producing area in China from 1978 to 2016.However,the proportion of rice planting area and total production of Yangtze River economic belt to which in the whole country dropped from nearly 70%to nearly 66.7%.In terms of quantity,rice planting area was reduced significantly,and the total production increased in the fluctuation in Yangtze River economic belt since the reform and opening-up.Meanwhile,the yield level was elevated steadily.Of all the factors increasing rice production,the unit yield contributed more to rice production than plant acreage,of all the factors decreasing rice production,plant acreage was the primary one.In the past 10 years,the contribution rate of rice unit yield was obvious,on the other hand,per unit yield of rice increased slightly,the rice planting area became the main factor affecting the stability of total production and regional pattern change(2)The rice planting area in the lower,middle and upper reaches of the Yangtze River economic belt showed a downward trend,and the total production increased.In terms of spatial pattern,the rice planting area was reduced in eastern regions,expanded in midland and kept stability in western regions.The trend of total production distribution was similar to that of rice area.Due to the influence of scale advantage in midland and the reduction of rice area(especially the area of double harvest rice)in downstream areas,rice production center of gravity moved westward as a whole.However,it remained in the middle and lower area of Yangtze River valley because of the higher yield level of rice production in downstream areas(3)Both the aggregated and scale comparative advantage indices were larger,showing a significant advantage of rice production in Yangtze River economic belt from 2004 to 2016.However,the corresponding efficiency comparative advantage index were relatively small.Compared with other rice producing areas in other regions,including South China,North China,Northeast China and Northwest China,both the aggregated and scale comparative advantage of rice production in Yangtze River economic belt ranked the second,this was mainly influenced by rice planting area.What’s more,rice production in Yangtze River economic belt lacked efficiency comparative advantage,but the index generally showed a slowly increasing trend.As to the region,rice production in midland possessed scale comparative advantage,but lacked efficiency comparative advantage,the difference of aggregated comparative advantage among regions was little.With the improvement of efficiency comparative advantage index,the advantage of rice production in the midland was being expanded.(4)Under the carbon emission constraint from chemical fertilizers,the overall technical efficiency and total factor productivity of japonica rice,early indica rice and late indica rice in Yangtze River economic belt were better than the one nationwide,showing an increasing trend.The increase of rice yield was partly due to green production technology,but mainly due to the input of production factors,especially in the upper and middle reaches.In the midland,the carbon emissions of chemical fertilizers in paddy fields were less,therefore,the increase of rice yield could still rely on essential factors of production.Rice production were limited by natural resources in the upstream areas,and the utilization efficiency of essential factors was better,however,rice production could not be significantly improved by increasing inputs.With more inputs,rice yield in the downstream areas was also much more,nevertheless,the paddy field environment needed to be improved,so the improvement of rice production was changing from relying on inputs to improving total factor productivity.(5)Technological progress became a major source of raising total factor productivity,and technical efficiency improvement played a smaller role in Yangtze River economic belt.The variation of productivity between different varieties of rice in different regions were different,and the index of productivity showed an increasing trend.To further enhanee the total factor productivity of rice production,producers needed to upgrade technology and promote efficiency.(6)Suggestions that planting area should be stable,new production methods should be applied,quality and efficiency should be improved,and green development for rice production should be promoted were put forward to protect and enhance the comprehensive capacity of rice production in Yangtze River economic belt.