河川開発と環境保全のコンフリクト存在下における意思決定システムに関する研究

抄録

In case a water resources development would result in bad influences on basin environment in recent years, this development plan yields various stakeholders and conflicts. So, it has become important to make a decision based on not only design flood discharge or safety of water utilization but also consciousness of related stakeholders. However, the past approaches for evaluating stakeholders' consciousness, such as CVM, TCM, and Alternative-Matrix method, have some demerits when we answer questionnaires or make discussion. The purpose of this paper is to make pluralistic evaluation of effects to stakeholders. Moreover, the method suggested in this paper enables comparison between one stakeholder's effect and another's one. This method makes a trigger for constructive argument and consensus building by presenting the result to stakeholders. For this purpose, we take the following two steps.
Firstly, the new approach for making the “satisfaction function” of a stakeholder is developed. This function means the degree of satisfaction corresponding to the stakeholder's criteria, and enables us to compare different criteria, such as flood control and environmental conservation. So-called “value function” resembles “satisfaction function”, but Keeney and Raiffa's conventional approach for making a “value function” has some problems about consistency between stakeholders. So, we propose the new approach for making “satisfaction function” by dividing a stakeholder to many groups who have different degree of necessity for improvement and evaluating each groups' degree of necessity.
Secondly, this process is applied to the Yoshino River movable weir problem as a case study. In this case, we set two stakeholders, one is about flood control and another is about ecosystem. Then their satisfaction functions are constructed. Finally, we evaluate each group's satisfaction degree of each alternative with “factor-profile method”. The result shows the trade-off relationship between flood control and environmental conservation, and the groups that easily suffer from harm. In this way, the model and method proposed in this paper enables us to evaluate fairly the value of water resources development and environmental conservation, and to know the effects that alternatives have on stakeholders.