黑龙江水稻孕穗期障碍型冷害及其对产量的影响

以连续3d以上日均气温≤18℃为指标判定障碍型冷害，利用黑龙江省稻作区1961—2006年每年7月中-下旬逐日平均气温和水稻产量资料，采用气候统计方法分析水稻孕穗期障碍型冷害的发生特征，在此基础上利用多元线性回归方法分析水稻实际单产与孕穗期障碍型冷害期间平均温度和低温持续时间的关系。结果表明：1961—2006年，黑龙江省稻作区水稻孕穗期障碍型冷害呈现不规律的时间变化特征，共有17a发生，发生范围大、持续时间长、平均气温低的年份有1964、1971、1990和2006年，20世纪80年代发生最多，为7a，20世纪90年代发生最少，为1a。研究期间，孕穗期障碍型冷害的发生频率在地域上呈现由北向南、由东向西减少的趋势，北部最多，西部最少；在同一冷害年内，孕穗期障碍型冷害的发生具有明显的区域差异，冷害的发生程度在区域上表现为东部重于西部，北部重于南部。水稻实际单产与孕穗期障碍型冷害期间平均温度和低温持续时间具有极显著的相关关系（P〈0．01），孕穗期障碍型冷害期间平均温度每下降1℃，水稻单产降低1234．177kg／hm^2，孕穗期障碍型冷害持续时间每延长1d，水稻单产下降104．208kg／hm^2。

Sterile Type Cool Injury of Rice during Booting Stage and its Impacts on Rice Yield in Heilongjiang Province

Based on the observation data of the daily air temperature from mid July to late July, and rice yield in 1961- 2006 in the rice planting areas of Heilongjiang Province, the temporal and spatial characteristics of the sterile type cool injury of rice were statistically analyzed. The relationships between rice yield and the daily mean air temperature, the duration of low temperature during occurrences of sterile type cool injury during rice booting stage were investigated by using the linear regression methods. The daily air temperature below 18℃ with three consecutive days during rice booting stage was regarded as the index to determine if the sterile type cool injury occurred. The results showed that the spatial characteristics of sterile type cool injury occurrence were irregular in the rice planting area in Heilongjiang Province from 1961 to 2006. There were seventeen years cool injury occurred. The years with the large scope, long duration and low daily air temperature were 1964,1971,1990 and 2006. During the 1980s,there were seven years the sterile type cool injury took place, which occurrence rate was the most frequently, while during the 1990s there was only one year the sterile type cool injury took place. The frequency of sterile type cool injury showed a decreased trend from the North to the South and from the East to the West of the Province, the largest was in the northern part and the least was in the western region. In the same year,sterile type cool injury occurred with a clear regional differences during rice booting stage, the degree of sterile-type cool injury was more serious in the eastern part than in the western part, and it was more serious in the north than in the south. Further investigation results showed that official rice yield was very significantly correlated to the daily air temperature and duration of low temperature during sterile type cool injury （ P 〈0.01 ） , the average air temperature dropped 1℃ , rice yield reduced 1234. 177kg/ha, and sterile type cool injury sustain