[Comparison of drought risk between transplanting and direct-sowing rice in the Sichuan Basin, China]

The quantitative evaluation and comparison of drought risks at each development stage and the whole growth period between transplanting rice and direct-sowing rice in Sichuan Basin can provide a scientific basis for the transformation and promotion of rice production technology in various regions. Based on the theory of natural disaster risk and the formation mechanism of rice drought risk, we evaluated and compared the drought risk in the whole growth period and the four development stages (sowing-jointing, jointing-booting, booting-full heading, full heading-maturity) between transplanting rice and direct-sowing rice, analyzed the vulnerability of disaster bodies, the sensitivity of disaster environment and the capacity of drought disaster prevention and reduction of rice drought in Sichuan Basin, using meteorological data in Sichuan Basin from 1961 to 2017, the observation data of rise production, agricultural statistics and the basic geographical information. The drought risk assessment model for Sichuan Basin was established, which was used to classify the results of evaluation. The results indicated that the drought risk of rice in Sichuan Basin was higher. The medium-risk areas in terms of the two planting methods were both the most widely distributed areas. The spatial-distribution characteristics of drought risk for the two kinds of rice were generally the same which was high in the middle and east of the basin, low in the southwest of the basin, and decreased from east to west and from the center to the surroundings. For the two planting methods, the greatest difference of rice drought risk appeared at the sowing-jointing stage. The drought risk of the direct-sowing rice at the sowing-jointing stage was significantly lower, and the distribution range was smaller than that of the transplanting rice. The distribution of the slight-low drought risk area of the direct-sowing rice was wider, but the high-risk area was slightly smaller.