Professor, Department head of Construction & Environmental Engineering, Graduate School of Science and Technology for Innovation, Yamaguchi University, Japan

Masahiko SEKINE started his research carrier on river water quality modelling, and he earned a Doctoral degree in Engineering from Kyoto University in 1991. After that, he has been mainly focusing on assessing the influence of human activities on living organisms, and conducted researches on coastal fish production modelling, aquatic toxicity assessment, fish preference modelling, river habitat simulation, river restoration and nature conservation projects, etc. He also served as a president of Austral/Asia chapter of the International Society for Ecological Modelling, a director of Ecology and Civil Engineering Society and Japan Society on Water Environment, and many committee members and secretaries in civil and environmental engineering field.

Speech Title: Seeking a simple and easy-to-use fish habitat evaluation procedure for river restoration

Abstract: Our group had been working around fish preference models to predict fish production, to estimate fish evacuation success from lethal environmental deterioration, to evaluate river habitat improvement works, to detect migration path through river drops and fishways, etc. In the initial stage of our research, we proposed a fish preference formula which allowed us adding / removing environmental factors without affecting other parameters. The first model handled environmental factors such as velocity, depth, turbidity, food, existence of plants, and population density. Later we added more physical factors such as air content, sound pressure, turbulence; chemical factors such as salinity and DO; biological factors such as home range, behavioral mode, rheotaxis. These researches had revealed that our preference model could explain the fish behaviour and distribution quite accurately. However, river authorities didn’t want to use our model for their restoration project since it seemed too complicated for practical use. Recent years we have been focusing on finding out a simple index to describe fish habitat condition for multiple fish species at once, and we reached EED (Eco-Environmental Diversity). EED is an environmental diversity index coupled with preference of multiple fish species. Through field observations, we revealed that EED has positive relationship with the number of fish species. We also developed a free software DHABSIM to calculate EED only from physical flow condition in a river. DHABSIM allows users to estimate EED before actual construction. In this presentation, I will describe our research history and theoretical background of EED.