Acta Geographica Sinica ›› 2019, Vol. 74 ›› Issue (9): 1803-1820.doi: 10.11821/dlxb201909008

• Climate Change • Previous Articles     Next Articles

Spatial-temporal characteristics of precipitation from 1960 to 2015 in the Three Rivers' Headstream Region, Qinghai, China

LIU Xiaoqiong1,2,WU Zezhou2,LIU Yansui3,ZHAO Xinzheng1,2,RUI Yang1,2,ZHANG Jian2,4()   

  1. 1. The Provincial Key Laboratory of Surface System and Environment Capacity, Northwest University, Xi′an 710127, China;
    2. College of Urban and Environment, Northwest University, Xi′an 710127, China;
    3. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    4. Institute of Silk Road Studies, Northwest University, Xi'an 710069, China
  • Received:2018-05-31 Revised:2019-08-18 Online:2019-09-25 Published:2019-09-25
  • Contact: ZHANG Jian E-mail:zhangjian@nwu.edu.cn
  • Supported by:
    National Social Science Foundation of China(16XGL015);Postdoctoral Science Foundation Special funded project of China(2017T100764);National Natural Science Foundation of China(41661042)

Abstract:

The Three Rivers' Headstream Region in Qinghai Province is the area with the most fragile ecosystem in China, its annual changes of the precipitation in the growing season are the key to the security of the water resources and the sustainable development of the ecosystem in the local area and the lower Lantsang River, Yellow River and Yangtze River. This paper studied the spatial-temporal characteristics of the precipitation in the Three Rivers' Headwater Region during the last 56 years by using the linear regression, Mann-Kendall test, heuristic segmentation algorithm, R/S, and EEMD et al. The results show that there is an obvious difference in the spatial-temporal characteristics of the precipitation with the variation of area and reason. The results are as follows: The precipitation series of study area showed a weak trend of getting-humid, and it increased significantly since the 21st century, the climate tendency rates of precipitation in the three sub-headwaters region are not the same; The annual and seasonal precipitation decreased from southeast to northwest, the summer precipitation of the Lantsang River Headwater Region and the autumn precipitation of the Yellow River Headwater Region decreased weakly, the areas where precipitation reduced weakly spotted in spacial distribution, the order of seasonal precipitation climate tendency rates of the Lantsang River and the Yellow River Headwater Region are spring, winter, autumn and summer precipitation, while the Yangtze River Headwater Region are spring, summer, winter and autumn precipitation(which are all positive); The decadal variation and the climate tendency rates of precipitation are more obvious; The multiple correlation coefficient between the climatic tendency rates of precipitation in spring, summer and longitude, latitude, altitude are significantly higher than that in winter; There was a wet turning signal in the middle and late 1990s, but the catastrophe point of the precipitation time series occurred around 2002; Inter-annual and low-value Inter-decadal prominent period are the main factors which caused the precipitation variation; With the exception of summer precipitation in the Lantsang River Headwater Region, the other seasonal and the annual precipitation changes showed a trend of different getting-humid; By comparison, the precipitation change in the Yangtze River Headwater Region is more representative than the other two regions in climate change of the Tibetan Plateau. Therefore, it is necessary to continue the research with more characterizing methods to further improve the detection accuracy of the variation process of the characteristics of climate series.

Key words: Precipitation series, statistical characteristics, EEMD, spatial and temporal evolution, the Three Rivers' Headstream Region