Abstract:

The fractal characteristics were discussed according to the fractal analysis of segments in lower Jingjiang River in this paper. The parameter of dimensions are changing between 1078 to 123 and are lower than those of Yellow River, Haihe River and Luanhe River and close to those of plain areas in lower Yellow reaches and upper Yangtze reaches. The result indicates the evolution of segment is mature period, which is disproportional to other segments of this catchment. This is maybe controlled by its geological settings, especially longterm slow subsidence of JianghanDongting Lake plain. After the watercourse is cut off, the fractal value decreases evidently associated with the simplification of watercourse. The curve cutoff of segment generally occurs between 119 and 123 of dimension. Thus the fractal value can be regarded as an early warning parameter.

Key words: watercourse, geomorphologic evolution, fractal characteristic, early warning parameter, Yangtze River, lower Jingjiang segment