不同比例尺下中国水系分维数关系研究

Comparative Study on Fractal Dimensions of River Basins in China at Different Map Scales

应用分形理论,再次验证整个中国水系及各流域水系分形特征的客观存在;通过比较1∶450万及1∶1 200万比例尺计算的分形维值大小及变化规律,表明单一尺度的分形规律在其它尺度下依然存在;大比例尺条件下计算得到的分形维值也大,且各层次不同流域的分维值在不同比例尺条件下的变化也呈现相同的趋势,表明图源比例尺对分维计算值的影响。

Fractal theory, which has already been widely used in various fields, provided new tools in geographical studies especially the scale issues. Fractal theory is used in this paper to study the fractal character of China river basins at 1：4 500 000 and 1：12 000 000 scales respectively, and the relation between the fractal character of the two scales is analyzed accordingly. Some significant conclusions are drawn as follows ： （ 1 ） The objective existence of fractal character of the river basins in China is approved again within larger scale. （2） The calculation and comparison of fractal dimensions of China＇s river basins show that the fractal rule in one scale also exists in other scales. （3） The larger the scale is, the bigger the calculated fractal dimension is, and the same trend is also seen in different hierarchy of river basins at different scales.