[Continuous-rain hazard of transplanting and direct-sowing rice in Sichuan Basin, China]

Continuous rain disaster is a kind of complex disaster with high frequency in the Basin area of Sichuan Province. Continuous rainy weather may appear in every growing stage of rice, with consequences on the yield and quality. Based on the meteorological data of 105 meteorological stations between 1981 and 2019, combining the observation data of rise production, agricultural statistics and the basic geographic information, we quantitatively evaluated and compared the continuous-rain disasters in the whole growth period and the four growth stages (sowing-jointing, jointing-booting, booting-early filling, mid-late filling-maturity) between transplanted rice and direct-seeded rice in the basin area of Sichuan Province. The results showed that the disaster index of continuous-rain for rice was higher in the sowing-jointing stage and the mid-late filling-maturity stage, higher in the northern and southwest edges of the basin, and lower in the middle, western and southern basin. The area with high-risk was relatively limited, which concentrated in the northern edge of the basin and scattered in the southern region of the basin. The low-risk area was the most widely distributed, which concentrated in the western and central parts of the basin. The total area of high-disaster areas for transplanted rice was 2.4 times as large as that for direct-seeded rice.