Abstract:

The variations of the accumulated temperature and the sunlight hours inMaqu grassland in recent 40 yearswere analyzed by using a non - parameterMann - Kendall testmethod and wavelet analysis. The results show that annual variation of accumulated temperature tended to increase, and the tendency rate of ≥ 0 ℃ accumulated temperature is 59. 5 ℃/10 a, and 33. 7 ℃/10 a for ≥ 10 ℃ accumulated temperature. The period corresponding to high oscillation center of ≥10 ℃ accumulated temperature is two yearsmore than that of ≥0 ℃ accumulated temperature; the low and high frequency oscillation tended to increase at the same time. The annual trend of sunlight hours is also increasing, and the tendency rate is 40. 2 h /10 a. By Spearman’s order correlation analysis, we know that the positive matching characteristic of light, heat and water is remarkable; the synchronous changes p resented inMay to Sep tember forwater and heat, and June to July for light and water. The app rop riate p recip itation, higher air temperature and the adequate sunshine are helpful to pasture’s growth ofMaqu grassland.

Key words: climate environment, characteristic, matching of light, heat and water, Maqu grassland

摘要：

利用趋势分析法、Mann - kendall非参数趋势检验法和小波分析法对玛曲县气象站近40 a的积温、日照时数进行统计分析,结果表明:积温年际变化呈增加趋势, ≥0 ℃积温倾向率为59. 5 ℃/10a, 极值出现在16 a振荡周期的跃变点处; ≥10 ℃积温倾向率为33. 7 ℃/10 a,极小值出现在10 a振荡周期的跃变点处;积温初日日期有提前的趋势,积温终日日期有推迟的趋势; ≥10 ℃积温强振荡中心对应的周期比≥0 ℃多2 a,次强振荡中心对应的周期少5～6 a,低频和高频振荡同时趋向增大;日照时数年际变化呈增加趋势,倾向率为40. 2 h /10 a,极小值发生在16 a振荡周期跃变点左右。Spearman秩相关分析,光、热、水的正匹配特征明显,其中牧草生长季5～9月水热同步变化, 6～7月光水同步变化。牧草生长状况应当从光、热、水三者的匹配关系考虑,降水正常、气温偏高、日照丰富
是最有利于牧草生长的草原气候生态环境。

关键词: 气候生态特征, 光热水匹配, 玛曲草原