Study On Sichuan Province Crop Production Potential Based On Climate Change

China is a country with a low per capita resources, and it is difficult to reverse the situation. Food security is related to social harmony and stability which needs to pay attention all the time. Only on the basis of knowing the current situation of crop production potential could we develop long-term measures to ensure food security is not shaken.This paper summarizes the research progress of crop production potential at home and abroad, introduces the common methods of calculation, and analyzes the main factors which affects the crop production potential. Choosing rice, wheat, corn and sweet potato to study the crop production potential is based of the combination of the actual planting conditions in the study area.Take counties (cities, districts) as basic assessment unit, and use the AEZ model (Agro-Ecological zones project) to calculate the thermal production, use the improved H.L.Penman formula to calculate crop evapotranspiration, determining the climatic production potential step by step. Compared with the original production potential, analysing the annual change and the relative change. Using ArcGIS10.1 to describe the spatial distribution of crop production potential in the study area, and then use quantitative and qualitative analysis to analyse the regional differences, simulate the changes of crop production potential under different temperature and precipitation changes finally. Combining the theoretical climate production potential with the actual production of unit area in the area, analyses the utilization degree of agricultural climate resources of different crops in 21 cities (states) in Sichuan Province. The main conclusions are as follows:(1) The production potential of major grain crops in Sichuan province showed significant growth, but the growth rate varied with the region and the crop. The growth of crop climatic production potential in hilly area of Sichuan basin is the most significant, followed by the basin region, the whole production potential growth of the crop is corn, followed by sweet potato, rice, wheat. The trend of the relative variability of crop climatic production potential and elevation trend of regional division are the same direction. That is, the lower the altitude, the terrain is flat, the relative change rate is smaller; the elevation is higher, the terrain is complex, its relative change rate is bigger.(2) The main food crops in Sichuan Province, rice, corn and sweet potato production potential generally is the North South high-low distribution. Because of the growing season of wheat and other three kinds of differences, the spatial distribution of climatic production potential and other three kinds of crops were slightly different, genenally lower in the south and higher in the north.The climatic production potential of wheat in the hilly region of the basin, the region of the basin and the Chengdu plain, reached 11421 kg/hm2, 10863 kg/hm2, and 10705kg/hm2 respectively. The thermal production potential of rice, corn and sweet potato in mountainous regions of Southwest Sichuan were the largest, which reached 21437 kg/hm2,30104 kg/hm2 and 35472 kg/hm2 respectively. The maximum thermal peoduction potential of wheat in mountainous canyons area of Western Sichuan, the average value reached 19249kg/hm.In Sichuan Province, the main food crop production potential by water attenuation degree from high to low are wheat, corn, sweet potato, rice, and the main reason is wheat’s growth season precipitation are not, and the other three kinds of crop growth periods are the most vigorous periods of natural precipitation every year. The thermal production potential in the northwest of Sichuan is larger than that of Sichuan Province, but its climatic production potential is much lower than the average level of the province. Because of the crop growth periods of the natural precipitation deviate too much from the crop growth periods of water demands and less precipitation in the thermal production potential of attenuation of, so that it becomes a climate production potential’s low value zone. The result shows that the lack of rainfall is one of the main factors restricting the Northwest Sichuan Plateau area’s crop production potential.(3)The effect of temperature on the variation of crop production potential in different regions of the specific performance when the temperature rise or fall at 1 centigrade, the area with the biggest change range is the region with lower annual temperature, and the annual average temperature is relatively small. The influence of the change of natural precipitation on the crop production potential is mainly reflected by the relationship between the water demands and the natural precipitation in the growing periods. When the natural precipitation is less than the crop water demands, the climatic production potential will be affected by the attenuation of the water coefficient. When the natural precipitation is greater than the demand for water of crops, climate production potential will decay. Crop’s climatic production potential can only reach the maximum when the amount of natural precipitation is equal to the crop water requirement or the disparity is not large.(4) Based on the analysis of the main grain crops agricultural climate resources in Sichuan Province, the utilization rate of rice climatic resources was the highest, followed by wheat and maize, and the utilization rate was 46.29%,38.05% and 28.22%, respectively. Corn’s average climatic production potential is high, which reached 18482 kg/hm2, but the utilization rate of agricultural is low. We can improve the corn’s utilization ratio of agricultural climate resources and increase the yield of maize by adopting the superior variety and the improvement of the cultivation level.This paper gives some suggestions on the research of crop production potential in Sichuan Province under climate change, but there are still some shortcomings. Due to the limitations of a variety of conditions, I have not use the most accurate mechanism model. But I hope that in the future research, the mechanism model can be used to update accurate crop production potential of the study area.