黑龙江省大豆作物系数的确定

摘要

作物系数是计算作物需水量，合理进行灌溉和水分资源调配的重要参数。依据1991—2011年黑龙江10个典型农业气象站大豆农业气象观测记录，运用统计学方法，确定了大豆实际平均生育期，利用FAO推荐的Penman－Monteith公式和根层水分平衡原理，计算出了大豆作物系数，并进一步分析了大豆作物系数的变化规律。结果表明，近20年，黑龙江大豆平均播种时间推迟5 d ，收获时间推迟10 d ，平均生育期为5月1日到9月30日，生育期延长5d。大豆作物系数在生育期内呈现出“单峰”变化趋势，结荚期的作物系数最大，为0．96，其次是开花期，为0．75，苗期和成熟期最小，为0．32；三叶期、分枝期和鼓粒期作物系数分别为0．60，0．62和0．71，全生育期平均作物系数为0．61。大豆的水分敏感期为结荚期和开花期。%Crop coefficient is an important parameter for calculating crop water requirements and reasonable distri-bution of irrigation water and water resources .According to the observated records from 1991 to 2011 in 10 typical agri-cultural meteorological stations of Heilongjiang province ,the average soybean growth stages were determined by using the statistical method ,the crop coefficients of soybean were estimated by using the FAO recommended Penman -Monteith Formula and water balance equation in root zoon ,and the variable rule of crop coefficient of soybean was further ana-lyzed .The results indicated that:In recent 20 years ,the sowing date of soybean was delayed average 5 days ,the harvest date was delayed 10 days ,and the average soybean growing season was from first day of May to last day of September . The soybean crop coefficient displayed unimodal distribution in whole growing season .The average crop coefficient in whole growing season was 0 .61 ,the highest value was 0 .96 at podding stage ,the second was 0 .75 at flowering stage , the lowest value was 0 .32 at seedling and maturing stages .The crop coefficients in three leaves stage ,branching stage and poddring stage were 0 .60 ,0 .62 and 0 .71 ,respectively .The water sensitive period was podding stage and flowering stage .