Evaluating Ecological Health of Small and Medium Sized Rivers in Rizhao by Index of Biotic Integrity Based on Fish
As the important components of fresh water ecosystem,small and medium sized rivers often produce great effects on regional environment quality.The ecological health was evaluated by index of biotic integrity based on fish(F-IBI)for Chaobai Rvier,Futuan River and Xiuzhen River,the small and medium sized rivers in Rizhao.6 core metrics were identified,which included species richness,proportion of omnivorous individuals,proportion of sensitive individuals,proportion of epipelagic eggs spawning individuals,proportion of special spawning mode individuals,fish catch by one sampling.Then the assessment criteria were proposed.Results showed that most reaches were in sub-healthy or fair state,which indicated that ecosystem structure and function of the reaches might have been impaired.Middle reaches of Chaobai Rvier and Xiuzhen River were in better health state than the lower and upper reaches,while that of Futuan River showed a descending trend from upstream to downstream.The Pearson's correlation analysis showed that the F-IBI value was significantly negatively correlat-ed with permangamate index(p<0.05).Discriminability test together with Mann-Whitney U test showed that the metric sys-tem for F-IBI was effective and could be regarded as a useful tool in health evaluation and health management for the small and medium sized rivers of this region.
small and medium sized riversriver health evaluationindex of biotic integrityfish community structure