Assessment of habitats on typical low hills in the Yitong River in Northeast China

Abstract

ABSTRACTThis study investigated the aquatic habitats on typical low hills in the Yitong River in Northeast China by applying the River Habitat Survey (RHS) method. The status of river habitats was evaluated on the basis of Habitat Quality Assessment (HQA) and Habitat Modification Score (HMS). The quality of habitats and the spatial distribution pattern of human disturbances were also analyzed. Results demonstrated that the HQA of 51 sites was between 24 and 66. On the basis of HMS, we found that 7.8% of the reaches are kept natural and 19.5%, 41.2%, 27.5%, and 3.9% of the reaches suffer from slight destruction, distinct degradation, serious degradation, and serious damage, respectively. HQA also exhibited a significantly negative correlation with HMS. HQAs did not evidently differ among upstream, midstream, and downstream habitats along the Yitong River. By contrast, HMS varied significantly. The upstream and midstream habitats were mainly influenced by water conservation structures. The downstream habitat was mainly affected by intensive land development for agricultural and construction purposes and by hydraulic structure construction in river embankments, discharge pipe installation, and bridge construction. Therefore, RHS results can intuitively reveal the conditions affecting river habitats and the factors causing river habitat degradation.