四川省单季稻高低温致灾因子危险性分析

开展单季稻高低温致灾因子危险性分析,可为四川省单季稻生产防灾减灾提供理论支持.基于1981年-2012年四川省26个气象台站单季稻观测资料和逐日气象资料,利用水稻高、低温灾害指标,从灾害发生频率、次数和强度等方面定量分析了四川省单季稻生育期内高温和低温致灾因子的危险性.结果表明:1981年-2012年四川省单季稻秧田期低温和灌浆结实期高温的发生频率较高,大部地区超过60%;秧田期低温和灌浆结实期高温的发生次数较多,大部地区在26~50次;秧田期低温和灌浆结实期高温的发生强度较高,大部地区分别为4~12天/次和6~9天/次.近30年来,四川省单季稻秧田期的低温发生次数和强度呈减少趋势;开花期高温发生次数基本不变,发生强度呈现降低趋势;灌浆结实期高温发生次数和强度呈增加趋势.四川省不同区域和不同生育阶段单季稻高温和低温致灾因子的危险性存在差异,需要因地制宜地应对气象灾害带来的不利影响,保障单季稻的安全生产.

Analysis of High and Low Temperature Hazard Risks for Single Cropping Rice in Sichuan

Analysis of high and low temperature hazard risks for single cropping rice can produce important theoretical support for regional disaster prevention and mitigation. Based on the rice observation data and meteorological data during 1981-2012 collected from 26 meteorological stations in Sichuan, the high and low temperature hazard risks for single cropping rice were quantitatively analyzed according to disaster frequency, disaster time and disaster intensity. The result showed that frequency of low temperature during the nursery period and high temperature during the seed-filling and ripening period were more than 60% in most of the study regions for single cropping rice in Sichuan. The times of low temperature disaster during the nursery period and high temperature disaster during the seed-filling and ripening period in most regions were 26-50 times. The intensity of low temperature disaster during the nursery period and high temperature disaster during the seed-filling and ripening period in most regions were 4-12 and 6-9 days/time, respectively. In the 30 years (1981-2012), the time and frequency of low temperature disaster during the nursery period for single cropping rice decreased, the time of high temperature disaster during the flowering period did not change significantly, and the intensity was decreasing, and the time and frequency of high temperature disaster during the seed-filling and ripening period increased. Large differences existed in high and low temperature hazard risks in different regions and different rice growth stages in Sichuan. Therefore, we need to address the negative impacts of meteorological disasters according to the local conditions so as to ensure rice production safety.