青海省 1961—2018 年侵蚀性降水时空变化特征

利用青海省41个气象站点1961—2018年逐日降水数据，采用常规统计学方法，统计逐年降水量/日数、侵蚀性降水量/日数，分析青海省降水和侵蚀性降水的时空分布特征。结果表明:青海省年降水量、降水日数、侵蚀性降水量、侵蚀性降水日数之间呈显著的幂函数关系,空间分布均从东南向西北逐步减少。从4个生态功能区分布来看，三江源地区年降水量最高，为469.3 mm，柴达木盆地全省最低，为99.4 mm；侵蚀性降水量柴达木盆地最低，为25.1 mm，东部农业区全省最高，为155.5 mm。1961—2018年青海省年降水量和侵蚀性降水量分别以8.1、4.7 mm/10a呈显著增加趋势，年降水日数表现为不显著的减少趋势，侵蚀性降水日数呈显著的增加趋势，变化速率分别为-0.5、0.2 d/10a。侵蚀性降水量和侵蚀性日数突变分别发生在2004年和2001年，突变后侵蚀性降水量和降水日数较突变前分别增加22.4 mm和0.7 d。1961—2018年青海省侵蚀性降水量和侵蚀性降水日数的贡献率平均为32.7%和6.5%，侵蚀性降水量和侵蚀性降水日数的贡献率分别以0.59%和0.21%呈显著增加趋势。

Temporal and spatial variation characteristics of erosive precipitation in Qinghai Province from 1961 to 2018

Based on the daily precipitation data of 41 meteorological stations in Qinghai Province from 1961 to 2018, the precipitation annual/days and erosive precipitation annual/days are counted by using conventional statistical methods to analyze the temporal and spatial distribution characteristics of precipitation and erosive precipitation in Qinghai Province. The results show that a significant power function relationship between annual precipitation, precipitation days, erosive precipitation and erosive precipitation days in Qinghai Province. With the increase of annual precipitation and annual precipitation days, the erosive precipitation (days) follows the power function relationship and increases rapidly. The annual precipitation, precipitation days, erosive precipitation and erosive precipitation days in Qinghai province gradually decreased from southeast to northwest. From the distribution of the four ecological functional areas, the annual precipitation in The three rivers source Region is the highest at 469.3 mm; Qaidam Basin is the lowest in the whole province at 99.4 mm, The erosive precipitation is the lowest in the Qaidam Basin at 25.1mm, and the erosive precipitation is the highest in The Eastern Agricultural Area at 155.5 mm. From 1961 to 2018, the annual precipitation and erosive precipitation in Qinghai Province showed a significant increase trend of 8.1 mm/10a and 4.7 mm/10a respectively, the number of annual precipitation days showed an insignificant decrease trend, and the number of erosive precipitation days showed a significant increase trend, with change rates of-0.5 D/10a and 0.2 d/10a respectively. The abrupt changes of erosive precipitation and erosive days occurred in 2004 and 2001 respectively. After the sudden change, the erosive precipitation and precipitation days increased by 22.4 mm and 0.7d respectively. From 1961 to 2018, the average contribution rates of erosive precipitation and days of erosive precipitation in Qinghai Province were 32.7% and 6.5%, and the contribution rates of erosive precipitation and days of erosive precipitation increased significantly at the change rate of 0.59% and 0.21% respectively.