Author(s): Jun-Zheng Liu; Xin-Hua Zhnag
Linked Author(s):
Keywords: Small-medium rivers; Macrobenthos; Habitat quality; Meandering degrees
Abstract: Small-medium size city rivers are confronted with the problem of low flow, water pollution and canalization. Meandering of river shapes is a new restoration method of river topography and geomorphology. However, there are relatively few studies on the influences of the habitat quality of the macrobenthos by different curvatures of meandering rivers. In view of this, this study uses twodimensional numerical model consists of hydrodynamic, sediment movement and bed morphology variation, to establish a habitat simulation model based on the Instream Flow Incremental Methodology (IFIM). A case study was carried out in the Jin-jiang River through Hua-yang town of Chengdu city. In order to evaluate the effectiveness of the model, we also carried out the following studies: (1) field investigation at different river reaches with continuous meandering of the Jin-jiang River to obtain the basic information of the hydraulic conditions, macro-benthos and its habitat. On the basis of these information, the suitability curve of macrobenthos to the key factors including water depth, velocity and sediment was established; (2) the effectiveness of meandering degrees on the habitat quality of the macrobenthos was evaluated subsequently. Through comprehensive analyses, it finally revealed the mechanism of improving habitat quality of macrobenthos in small-medium city rivers by different meandering degrees. Results of this study can provide theoretical and technical supports for the improvement and restoration of hydro-environment and ecological conditions of small-medium city rivers.
Year: 2018