关键词: 风蚀, 气候侵蚀力, MHF小波, 多时间尺度, 农牧交错带

Abstract:

The study focused on the climatic erosivity time series of past long years in agro-pastoral ecotone of northern foot of Yin Mountain, Inner Mongolia, China, based on the meteorology data of wind speed, precipitation, temperature, humidity and so on. The temporal-frequency multiscaling variations and abrupt change features of climatic erosivity were analyzed by the MHF wavelet method which contributes to reveal the multi-scale variations characteristics of climatic erosivity, as well as the periods and abrupt change points of climatic erosivity series in different time-scale. Meanwhile, the relationship between the sandstorm phenomenon and the wind erosion climatic erosivity was obtained in the meteorology. The results showed that there were obvious staggered features about the variations of climatic erosivity in agro-pastoral ecotone of northern foot of Yin Mountain. Furthermore, it is found that approximate 16-year period-oscillation of climatic erosivity variations is the strongest. In addition, the sandstorm is more frequent where the larger wind erosion climatic erosivity is. Finally, the wavelet coefficients patterns exhibit a strongly reducing trend in climatic erosivity in the future years in long-term, but in short-term, there is a transition from larger climatic erosivity to smaller one.

Key words: wind erosion, climatic erosivity, MHF wavelet, multi-time scale, agro-pastoral ecotone