| Rice Production in the middle-lower yangtze area plays an important role in the Chinese rice Production, but the area is often affected by high temperature, then rice production is damaged. In this study, the impact of high temperature on season rice is researched with the remote sensing crop model in the middle-lower yangtze area. Firstly, the data of MODIS surface reflectance and land use types are used to extract the season rice planting area as the basis for yield display. Secondly, the remote sensing crop model is modified by the relationship which is building with the data from the agro-meteorological sites; Thirdly, the states of high temperature is analyzed in the time scale and spatial scale in the middle-lower yangtze area; Finally, the impact of high temperature on season rice is discussed in the base of yield from the model and the high temperature statues. The main conclusions are:(1) The season rice area extracted from the data of the MODIS surface reflectance and land use types is compared with the provincial statistical data and the coefficient of determination is 0.99, with county scale statistical area, the coefficient of determination R2 reached 0.8188. All of them are through the significant test at 0.01;(2) The rice yield in 2003-2012 is simulated from the improved RS-P-YEC model, and the yield is compared with the county statistical production.The coefficient of determination reaches 0.5578, the root mean square error(RMSE)is 52.64 kg / ha, and the average relative error is 9%. It indicates that improved model can more accurately simulate the impact of high temperature on rice production;(3) The high temperature days of the middle-lower yangtze area is an increasing trend in nearly 30 years and there is no mutation through the analysis of the spatial distribution of high temperature days, the feature of interannual variation, the Mann-Kendall mutation testing, the use of climate trend rate and the temporal changes with the EOF analysis;(4) From the analysis of the high temperature impact on rice yield, it can know that the proportion of rice production reduction rate in each interval is related with the proportion of high-temperature frequency in each interval. In detail, the high temperature frequency in the range 0-5 is corresponding to the rice production reduction rate in the range 0-10%, the range 5-10 corresponding to 10-20%, 10-15 corresponding to 20-30%, 15-20 corresponding to 30-40%, the greater than 20 corresponding to the greater than 40%. When the proportion of high-temperature frequency increases, the proportion of rice production reduction rate will increase at the same time. |
