岷江上游日径流过程分维分析及其生态脆弱性表征

The fractal analysis of the streamflow hydrographs and ecological vulnerability in the upper reaches of Minjiang River

运用分形理论的计盒维数原理,采用网格法研究了岷江上游日径流过程线的分形特征.通过计算紫坪铺站、姜射坝站、桑平站的日径流过程分形维数,发现各测站间的分维数变化上存在很大的联系,日径流过程分维数的变化趋势基本一致.将姜射坝站日径流过程线分维数与岷江上游生态脆弱性结合进行分析,分维在一定程度上还可以是生态脆弱性的表征.因此分形分维理论为水文学和生态学研究提供了新思路.

The grid technique of Box-counting methods is applied to fractal dimension of daily streamflow hydrograph in the upper reaches of Minjiang River. Analyzing the fractal dimension of the daily streamflow hydrographs at Zipingpu station, Jiangsheba station and Sangping station, we find the fractal dimensions in these stations are closely related. It shows that the interannual variation of fractal dimension obtained from the hydrology stations located in the same catchment is roughly consistent. Employing linear regression model, the fractal dimension of daily streamflow hydrograph at Jiangsheba station slightly increases with ecological vulnerability of five counties in the upper reaches of Minjiang River.