JOURNAL OF NATURAL RESOURCES ›› 2019, Vol. 34 ›› Issue (4): 785-801.doi: 10.31497/zrzyxb.20190409

• Resource Ecology • Previous Articles     Next Articles

Spatial and temporal variations of rainfall erosivity at each level in Taihang Mountain

LI Wei-jie1(), WANG Jian-li2()   

  1. 1. School of Geography Science, Southwest University, Chongqing 400715, China
    2. Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing 400715, China
  • Received:2018-08-27 Revised:2019-02-19 Online:2019-04-20 Published:2019-04-20

Abstract:

This paper is mainly based on daily rainfall data from 76 meteorological monitoring stations in the Taihang Mountains and its surrounding areas from 1954 to 2016. A simple model is established to simulate the annual rainfall erosivity based on different magnitudes of aggressive annual rainfall. The climatic trend rate, wavelet period analysis, center of gravity model, Co-Kriging interpolation, Mann-Kendall non-parametric trend test and mutation analysis were used to analyze the spatial and temporal variations of rainfall erosivity and their influencing factors. The results show that: (1) The simple model of annual rainfall erosivity in the Taihang Mountains area is y=0.182x11.095+5.463x20.982+9.401x31.017+15.258x4-26.753, and the erosivity of rainfall over years showed a slight upward trend, and it increased by 2.4 MJ·mm·hm-2·h-1·a-1 in 10 years. There is also a major cycle of about 20 a and a small cycle of 6 a, and significant mutations occurred in 1996. The eclipse of moderate rain and heavy rain showed an upward trend in 63 years, while the violent rain and extraordinary rainfall erosivity showed a downward trend. The spring and autumn seasons are mainly affected by moderate and heavy rain erosivity, while summer is mainly affected by excessive rainfall erosivity. (2) The maximum rainfall erosivity of all magnitudes is mainly distributed in the southeastern part of the Taihang Mountains and the Wutai Mountain areas. The minimum is mainly distributed in the northeastern part of the study area. Using the center of gravity model, we found that the gravity center of each magnitude of rainfall migrating migrates to the east and northeast in spring and summer, while that of the autumn and winter seasons migrates to the south and southwest, forming a cycle that is consistent with the control time of the winter and summer monsoons. (3) There was a significant positive correlation between rainfall erosivity and erosive rainfall in different magnitudes in the Taihang Mountains (P<0.01). Heavy rain and extraordinarily heavy rainfall erosivity were significantly negatively correlated with latitude and altitude (P<0.05). This is mainly related to factors such as subtropical high pressure movement, topography, elevation and natural geographical environment.

Key words: rainfall erosivity at each level, center of gravity model, spatial and temporal variations, Taihang Mountains