基于CI指数的黑龙江省作物生长关键期干旱变化

利用1961—2008年黑龙江省逐日气象观测资料,计算综合气象干旱指数（CI）,分析黑龙江省作物生长关键期（5—8月）气象干旱频率和气象干旱强度变化。结果表明：黑龙江省作物生长关键期干旱频率1960年最大为79%,1980年最小为58%,干旱频发中心位置变化不大,主要出现在松嫩平原西南部,但集中区向北转移。黑龙江省作物生长关键期干旱强度1960年为最强,其次为2000年,干旱强度最大区域基本稳定在松嫩平原西南部和三江平原中东部。2000年以来,作物生长关键期干旱频发且强度加大,北部渐频、渐强,原来较少发生干旱的三江平原干旱也时有发生且强度较大。

Drought changes of critical period of crop growth in Heilongjiang province based on CI index

Based on the daily meteorological data from 1961 to 2008,the meteorological drought comprehensive index（CI）was calculated,and the changes of drought frequency and drought intensity during the critical period of crop growth（from May to August）in Heilongjiang province were analyzed.The results show that the maximum and minimum drought frequencies are 79% and 58% and appear in 1960 and 1980,respectively.The position of drought center seldom changes,and most are located in the southwestern Songnen plains and focus areas move northward.The largest drought intensity occurs in 1960,then in 2000,and the larger areas of drought intensity are steadily located in the southwest Songnen plains and the middle and eastern Sanjiang plains.The drought has been frequent and intensity has increased during the critical periods of crop growth since 2000,especially in the north regions.In the past,drought event is seldom in the Sanjiang plains,but now it occurs from time to time and the intensity is stronger.