Hirokazu Haga

RIVER ENVIRONMENT EVALUATION USING MULTIVARIATE ANALYSIS WITH INTEGRATED WATER QUALITY AND RIVER FLOW TYPE INDICES BASED ON FISH DATA

It is necessary to evaluate the characteristics of river environment for planning river works and for setting an environmental target of preservation and improvement of habitats. Therefore the technique to analyze the relation between the distribution of living things and physical, chemical and biological environments of river habitats is required. In this paper, we presented an integrated water quality index and an integrated river flow type index. The latter was based on results of principal component analysis applied to the factors involved in HIM (Morishita, 1998). The integrated indices were used as criterion variables for a multiple regression analysis of fish data and some indicator species were presented. The multiple regression model was used for the estimation of integrated index values of verification rivers and showed good performance.