寒地水稻障碍型冷害指数构建及应用——以辽宁省为例

东北地区水稻障碍型冷害常规评估多采用温度和低温持续天数2个指标,为实现定量化评估和预报,需构建一种基于多因素的综合性障碍型冷害指数。本文基于水稻温度适宜度模型,以温度和低温持续天数为基础,综合考虑三基点温度对水稻生长发育过程的影响,利用辽宁省近50年的日平均温度和水稻发育期数据,构建水稻障碍型冷害指数(RSCDI),并利用该指数对辽宁省水稻障碍型冷害变化规律进行分析和试预报。结果表明：①1961-2010年的50年间,有20年发生了局部轻度冷害,14年发生了局部中度冷害,10年发生了局部重度冷害,未发生区域性及大范围冷害。②冷害发生频率最高的年代为1971-1980年,1981-2000年发生频率呈下降趋势,发生频率最低的年代为1991-2000年,2001年以后发生频率上升、且范围呈现扩大趋势;冷害发生范围主要分布在辽宁西部和东北部地区。随着气候变暖,冷害发生频率和范围虽有一定程度的下降,但辽宁省水稻障碍型冷害发生的不确定性仍存在。③利用RSCDI对2011-2014年辽宁省水稻障碍型冷害进行试预报,结果仅建平县2012年和2014年在开花期发生中度冷害,其他地区无冷害发生。

Construction and application of Rice Sterile-type Cold Damage Index in cold area: A case study of Liaoning Province

Temperature and consecutive cold days are commonly used to evaluate rice sterile-type cold damage in Northeast China. In order to realize quantitative evaluation and prediction, it is necessary to construct a comprehensive index of sterile-type cold damage using multiple factors. Based on a temperature suitability model, temperature and consecutive cold days, and considering the effects of three fundamental points temperature on rice's growing process, this study constructed the rice sterile-type cold damage index (RSCDI) by using the data of daily mean temperature and rice growth period in recent 50 years in Liaoning Province. It then analyzed the occurrence tendency of rice sterile-type cold damage, and forecast cold damage in Liaoning Province with RSCDI. The results are as follows: (1) During the 50 years from 1961 to 2010, local light cold damage happened in 20 years, local moderate cold damage occurred in 14 years, local severe cold damage occurred in 10 years, and there was no occurrence of regional and large scale cold damage; (2) The highest frequency of cold damage was in the 1970s. The frequency decreased from 1981 to 2000, and the lowest frequency of cold damage was in the 1990s. But there was an increasing trend after 2001. Cold damage mainly occurred in the western and northeastern parts of Liaoning Province. With climate warming, the frequency decreased to some extent, but the occurrence of rice sterile-type cold damage was uncertain in Liaoning Province; (3) The forecast of rice sterile-type cold damage in Liaoning Province from 2011 to 2014 using RSCDI shows that cold damage will not appear in most areas, but in Jianping County moderate damage may occur in the flowering period in 2012 and 2014.