摘要
首先分析西峰1971～2004年先年7～9月夏闲期降水量与次年冬小麦产量相关关系,进而利用陇东15个气象观测站1971～2004年7～9月降水资料,讨论降水的时空分布特征.结果表明：7～9月降水量与次年冬小麦气象产量通过0.01信度检验,达到显著相关水平;降水量年际最大值出现在2003年,为464.8 mm,最小值出现在1991年,为130.2 mm,最大值是最小值的3.6倍,年际周期以7 a周期最为显著,年代际以13 a长周期最为明显.降水量年代际变化明显,上世纪70、80年代降水正常或略偏多;90年代降水普遍偏少或特少,降水距平均为负值;2001年以来,降水明显偏多.降水总量以正宁为最大值中心,向西及西北分为两支逐渐减少,中部的华亭成为次大值区域,这样的分布特征与陇东的地理和地形条件密切相关.
Based on the example data of Xifeng during July to September from 1971 to 2004, the correlation of precipitation in summer unoccupied with the winter wheat output of next year was obtained. And then the characteristic of space-time distribution was discussed using the precipitation data from July to September of 1971-2004 of 15 weather stations in the east of Gansu. The results showed that the correlation of the precipitation from July to September and the meteorological output of the winter wheat of next year exceeded 0.01 letter degrees and reached the prominent level; The annual precipitation changed obviously between years, the minimum precipitation appeared in 1991, was 130.2 ram, while the maximum appeared in 2003, was 464.8 mm, which was 3.6 times large as that of minimum; there was an obvious planting-year-cycle with seven years and a year-cycle with thirteen years; The precipitation changed obviously in different cycles; the precipitation in 1970s＇ and 1980s＇ was normal or slightly much, while it was generally slightly little or very little in the 1990s＇, it＇s average distance value was negative; since 2001 the precipitation has been obviously too much. The maximum value center of the total precipitation was in Zhengning, and then reduced gradually in 2 directions to the west and to the northwest, Huating was the second large precipitation area, and such distribution characteristic is closely related to geography and topographical condition in the east of Gansu.
出处
《干旱地区农业研究》
CSCD
北大核心
2006年第6期125-128,146,共5页
Agricultural Research in the Arid Areas
基金
科技部科研院所社会公益研究专项"西北农作物对气候变化的响应及其评价方法"(2005DIB3J100)
关键词
陇东
夏闲期降水
时空分布
冬小麦
产量
east of Gansu
Winter wheat
Precipitation in summer unoccupied
output
space-time distribution
