黑龙江省玉米生长期冷害与干旱混合发生对产量的影响

基于1981-2016年黑龙江省玉米农业气象观测站资料,利用国家气象行业标准中≥10℃积温距平、水分亏缺指数(KCWDI)指标分别判识玉米出苗-抽雄期冷害、干旱,规定同一站点同一年份内冷害、干旱均有发生为2种灾害混合发生,分析其时空分布特征,以逐步回归方法构建积温距平、KCWDI与玉米单产的关系,并探讨2种灾害混发逆境对玉米产量的影响。结果表明:1981-2016年间,研究区玉米出苗-抽雄期≥10℃积温距平对气候变暖具有明显响应,呈显著增加趋势(P<0.01),空间上呈北低南高特征;KCWDI随时间呈波动式下降变化(P>0.05),空间上表征为西多东少趋势,较好反映研究区水分资源配置特征;在分析期内,各站玉米出苗-抽雄期冷害、干旱混合发生年数为2~12年,研究区累计发生94年,两种灾害混合发生随时间呈减少趋势,1990年代中期以前密集发生,之后发生频率下降,空间上,两种灾害混合发生表现为由西至东减少趋势,松嫩平原西部为频发区;玉米出苗-抽雄期≥10℃积温距平、KCWDI与玉米单产存在显著或极显著的相关关系(P<0.05或P<0.01),≥10℃积温距平下降、KCWDI增大,玉米产量呈下降趋势;玉米出苗-抽雄期冷害与干旱混发逆境对玉米产量以负效应影响为主。

Effect of Hybrid Occurrence of Cold Damage and Drought on Maize Yield in Heilongjiang Province

Based on the data of corn Agrometeorological Observatory in Heilongjiang Province from 1981 to 2016, the accumulated temperature anomaly (>10 C) and water deficit index ( K CWDI ) in the national meteorological industry standard were used to distinguish the cold injury and drought during the period of maize emergence and tasseling. It was stipulated that the cold injury and drought occurred in the same station in the same year should be a mixture of two disasters. The relationship between accumulated temperature anomaly, K CWDI and maize yield was constructed by stepwise regression analysis, and the effects of mixed disaster adversity on maize yield were discussed. The results showed that during 1981-2016, the accumulated temperature anomaly of Maize at Seedling-heading stage (>10 C) in the study area responded significantly to climate warming, showing a significant increasing trend ( P <0.01), showing the characteristics of low in the north and high in the south in space. K CWDI fluctuated with time ( P >0.05). Spatially, K CWDI tended to be more in the West and less in the east, which better reflected the characteristics of water resources allocation in the study area. During the analysis period, the number of years of cold injury and drought mixed occurrence in Maize emergence-heading period was 2-12 years. The cumulative occurrence of the two disasters in the study area was 94 years. The mixed occurrence of the two disasters tended to decrease with time. It occurred intensively before the mid-1990s and then decreased in frequency. Spatially, the mixed occurrence of the two disasters decreased from west to east. Less trend, the western Songnen Plain is a frequent area;the accumulated temperature anomaly of Maize at Seedling-heading stage (>10 C), K CWDI and maize yield have significant or extremely significant correlation ( P <0.05 or P <0.01),(>10 C accumulated temperature anomaly decreased, K CWDI increased, maize yield showed a downward trend;the cold injury and drought mixed adversity at Maize Seedling-heading stage. The negative effect of environment on maize yield was dominant.