Analysis and Regionalization of Rice High-Temperature Harm Risk in Hubei Province Based on Disaster Risk Theory
High-temperature heat damage is one of the main meteorological disasters in the Yangtze River Basin,and scientific assessment of heat damage risk is the basis for disaster prevention and reduction.This study is utilising meteorological observation data from the past 60 years to analyse the spatiotemporal distribution characteristics of high-temperature heat damage in Hubei.Based on the basic theory of natural disaster risk,a high-temperature heat damage risk assessment model is established,which includes factors such as the heat damage intensity that affects the critical period of rice seed setting rate,the actual exposure of the disaster bearing body during the disaster occurrence,and the vulnerability of the disaster.Risk analysis and zoning are conducted.The results show that the period with a high probability of high-temperature weather occurrence is late July,with the 6th pentad in July being the highest.From the perspective of the high-temperature heat damage risk index,the heat damage risk of rice heading and flowering in the third pentad of July is the highest,and thereafter,the heat damage risk decreases over time.The current heading and flowering period of one season mid season rice in Hubei is at a high-risk period,and delaying it for 5 days can reduce its heat damage risk index by about 20%;delaying for more than 15 days reduces the heat hazard risk index by more than 50%.The southeastern and northwestern regions of Hubei are high-risk areas for high-temperature heat damage.For the southeastern region of Hubei,it is recommended to postpone the sowing period by about 15 days or choose more heat-resistant varietals to reduce the impact of high-temperature heat damage.Heat resistant varieties should be selected in the northwest of Hubei to reduce the risk of high-temperature and heat damage,and it is not advisable to postpone the sowing date to avoid the impact of autumn rain in western China on the rice harvest period.Due to the inferior water resource conditions compared to the Jianghan Plain in northern Hubei,and the frequent occurrence of high-temperatures accompanied by drought,it is recommended to choose heat-resistant varieties and moderately control the rice planting area in the northern Hubei rice region.Regenerated rice should try to choose some heat-resistant varieties and strengthen farmland management to cope with high-temperature and heat damage.