晋南低温与霜冻发生规律及其对棉花生产的影响

Effects of Low Temperature and Frost to Cotton Production in Southern of Shanxi Province

温度是影响棉花生长的重要因子。研究了晋南主产棉区——运城市棉花生育期气温变化的特点,结果表明,近年来运城市的终霜冻有20%的年份晚于4月1日(正常年份为3月上旬),早霜冻有27.3%的年份早于10月5日(正常年份为11月上中旬);在播种出苗期,气温不稳定,有66.6%的年份在最低气温10℃稳定通过3 d以后,又出现10℃以下的低温3 d左右;从苗期到吐絮期出现对棉花发育不良的气温均有10%以上的概率。

Temperature is one important factor for cotton. The air temperature is analyzed in cotton production area in south- ern of Shanxi Province during cotton growth stages.In recent years, occurrence probability of final frost day after April 1 was 20%, which occurred during the first ten days in March in normal years; 27.3% for early frost day before Oct. 5 which occurred during the first and middle ten days in November in normal years. 66.6% probability of low temperature years happened when air minimum temperature stably pass through 10℃- for three days and subsequently occurrences below 10 ℃ for three days during sowing and seedling stages. 10% more probability of disadvantage temperature occurred during the tatat growth stages.