MA Wei, PENG Jing, PENG Wenqi, HUANG Wei and LUO Huihuang

China Institute of Water Resources and Hydropower Research, Beijing 100038, China

Abstract: River habitats have many important characteristics such as multi-scale, multi-level, patch distribution and dynamic changes. The quality of river habitats is generally evaluated by the fitness functions of key environmental factors related to river habitats. This paper starts from research on velocity and water depth of stream habitats both in China and overseas, as well as the local stream fishes' preference of velocity, water depth and water temperature, and then takes the Hemibarbus labeo, a fish preferring slow cur-rent, as the indicator to analyze key environmental factors in its habitat of Oujiang River southwest of Zhengjiang Province, China. In view of the natural environment features and aquatic biodiversity in Oujiang River, the fitness curves of key environmental factors, such as velocity, water depth, water temperature and water quality, are discussed. This paper uses the fitness curve of key environmental factors as four determinants to define the graded evaluation standard of river habitats and to grade the quality of river habitats into optimum, good, moderate and bad. The results can provide scientific support for river habitat quality evaluation and ecological adaptive management.

Key words: river habitat; fitness curve; graded evaluation standard; Hemibarbus labeo; Oujiang River

Published in: Journal of China Institute of Water Resources and Hydropower Research, No. 1, 2016