【摘要】 为了解内蒙古阴山北麓农牧交错带的风蚀气候侵蚀力变化特征及规律,在收集多年风速、降水、气温、相对湿度和沙尘暴气象站观测数据的基础上,计算了典型区域风蚀气候侵蚀力。引入MHF小波函数,对该时间序列进行小波分析,揭示了区域风蚀气候侵蚀力变化的多时间尺度的复杂结构,分析了其在不同时间尺度下的周期性和突变诊断点。结合沙尘暴发生日数的观测资料,进一步分析风蚀气候指数与沙尘暴发生日数的尺度变化关系。研究表明:内蒙古阴山北麓农牧交错带风蚀气候侵蚀力具有明显的阶段性特征,以16 a的周期振动最强;在整个时间域上,区域风蚀气候侵蚀因子与沙尘暴日数的变化具有较好的对应关系,即风蚀气候指数偏大期对应沙尘暴日数偏多期,风蚀气候指数偏小期对应沙尘暴日数偏少期;并预测在未来一段时间内风蚀气候侵蚀力较大时间尺度变化处于增强的偏小期,但较小尺度表现出由大到小的过渡。更多还原

【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.更多还原