青海贵德地区冬小麦冬前热量条件变化分析

Analysis on Heat Conditions Change of Winter Wheat before Winter in Guide Area of Qinghai

对青海贵德地区冬小麦冬前热量条件变化进行了分析。结果表明,近55年来,贵德地区日平均气温≥0℃终日、冬小麦冬前≥0℃积温和9—11月平均气温年际间波动较大,总体线性增长趋势明显。小波分析表明,≥0℃终日的变化周期集中在中低频区,1970年代以前为6年左右周期,1970—1980年代以15年左右周期为主,1980年代末期以后以10年左右周期为主。近5年来,偏早周期已经闭合,偏晚周期已经开始;冬前≥0℃积温,1970年代末期以前以6年周期为主,1970年代末期至1990年代,以9年周期为主,1990年代末期以后以3年左右的短周期逐渐增强。综合分析表明,未来3～5年冬小麦冬前热量仍呈现增加趋势,年际间波动明显,冬小麦播种期应根据气象部门中长期气候趋势预测适当调整。

The heat conditions change of winter wheat before winter in Guide Area of Qinghai were analyzed.The results showed that the interannual fluctuation of daily average temperature≥0 ℃days, ≥0℃ accumulated tempretures of winter wheat before winter and average temperatures in September to November were larger.The overall trend was clearly linear growth. The wavelet analysis showed that change cycle of ≥0℃ days concentrated in the low frequency region,with about 6-years cycle before1970,15-years cycle based in 1970—1980,and 10-years cycle based after the end of 1980. Partial early period has been closed,and late cycle has started in the past five years, ≥0 ℃ accumulated tempretures before winter had 6-years cycle based in the late-1970 s,and had9-years cycle based in late and 1990 s. It had about three years short period gradually increase after the late of 1970 s to1990s. Comprehensive analysis showed that before winter heat of winter wheat in the next 3—5 years was still showing an increasing trend,with significant fluctuations between years. The sowing time of winter wheat should be adjusted according to the meteorological department forecast the long-term climate trends.