Taking the annual mean runoff of Huayuankou section of the Yellow River in the period of 1953~2002 as time series data and based on G-P algorithm,the paper calculates the steady estimate of correlation dimension and Kolmogorov entropy by using the least-squares method.

It is believed that forests use more water than grasslands and hence reduce average annual streamflow; however,the spatial distribution of vegetation restoration and its impacts on annual streamflow,espe-cially on the regional scale,are poorly known.

Multi-scale analysis of annual average streamflow at Hongjiadu Hydropower Station based on HHT method;