临汾市冬小麦生育期降水对产量的影响分析

Impact of Precipitation during the Growth Period on Winter Wheat Yield in Linfen City

冬小麦产量的变化主要受降水、温度、光照等气象要素的影响,其中,以降水尤为明显。冬小麦全生育期对降水量的需求不尽相同,拔节—抽穗期和抽穗—乳熟期是冬小麦需水最大的时期,降水对产量的影响也最大。临汾市冬小麦生育期降水量的变化是影响冬小麦产量的主要因素。1985—2008年冬小麦产量和降水的对比分析发现:4月份(拔节—抽穗)降水量的多少对冬小麦产量影响很大,降水量与小麦产量呈正相关,在适宜的范围内,降水量偏多的年份为增产年,降水量偏少的年份为减产年;在冬小麦全生育期,临汾市多年平均降水量小于冬小麦生育期需水量;在春季降水异常的年份中,降水量偏少比降水量偏多对冬小麦减产影响明显;在冬小麦生育后期,降水因素(降水量与降水日数)是影响冬小麦产量的主要因素。

The winter wheat yield is mainly affected by changes of precipitation,temperature,light and other major meteorological elements,in which precipitation is particularly evident.Demand for precipitation is very different in whole growth period of winter wheat,and at jointing-heading stage and heading-ripeness stage water demands are the largest,and the impact of precipitation on yield is maximal.In Linfen,the precipitation during the growth period is the main factor to winter wheat yield.Compared the winter wheat yields with rainfall from 1985 to 2008,the results were： 1,In April（jointing-heading） the impact of rainfall on winter wheat yield was large and showed a positive correlation with the yield.In the appropriate range,the years with more precipitation were years of production increasing;those with less precipitation were the production reducing years.2,For the whole growth period,the average annual precipitation in Linfen was less than the water demand during the growth period.3,In the years of spring precipitation anomalies,the impact on production reducing of less precipitation was more obvious than that of more precipitation.4,In the late growth period of winter wheat,precipitation elements,precipitation and precipitation days,were major factors to winter wheat yield.