基于当量积温对寒地水稻生长季低温冷害年的判定

Identification on Cold Damage Year Based on Accumulated Equivalent Temperature during Rice Growth Season in Cold Region

基于水稻生物学性质,根据气温昼夜节律和水稻温强系数研究成果,从热量影响水稻发育的多种角度出发,设计当量积温、负当量积温、热量匹配累积指数三种水稻生长季热量表征指标,研究寒地水稻低温冷害的判识方法。采用21a滑动平均法,获得黑龙江省1971-2016年水稻生长季各热量指标的距平百分率,分析其对低温冷害的判识能力。结果表明:各热量指标距平百分率取值越低,对冷害的指示能力越高;利用加权隶属度模型构建三者综合距平百分率冷害判定模型,距平百分率>-5%为无冷害,-10%<距平百分率≤-5%为轻度冷害,-15%<距平百分率≤-10%为中度冷害,距平百分率≤-15%为重度冷害;综合距平百分率能够判识水稻生长季的低温冷害,且能反映冷害程度,对典型冷害年的判识准确率达100%;黑龙江省冷害群发性特征非常明显,如1971、1972、1976、1981、1983、1992、2002和2009年典型冷害年,不仅冷害发生区域广,且冷害程度较重;1986、1987、1989、1993、1995和2003年为轻度或局地冷害年。

Based on rice biological characteristics, circadian temperature rhythm and temperature coefficient, taking accumulated equivalent temperature, negative accumulated equivalent temperature and heat matching index as index,the identification method for cold damage year was studied. By using moving average method on 21 years, departure percent was obtained for three factors in Heilongjiang province from 1971 to 2016, and the identifiable ability was analyzed. The results showed that identification ability was stronger, when the departure percent of every factor decreased more. This identification model for cold damage based on integrative departure percent was established by using weighted membership model. When departure percent was above-5%, named as zero cold damage year, when departure percent was above-10% and below-5%, named as slight cold damage year, when departure percent was above-15% and below-10%, named as moderate cold damage year, and when departure percent was below-15%,named as severe cold damage year. Integrative departure percent could indicate cold damage during rice growing season, and could reflect different degrees of cold damage, and totally indicated typical cold damage years. Cold damage performed a feature of outbreak in Heilongjiang province, for example in 1971, 1972, 1976, 1981, 1983,1992 and 2009. In these years, cold damage extended over extensive regions, and the damage degree was more severe, the other damage year was slight degree or regional damage, including 1986, 1987, 1989, 1993, 1995 and2003.