Cyanobacterial bloom control in Taihu Basin: Analysis of cost-risk analysis framework based on cooperative game

Cyanobacterial bloom has posed a serious threat to the sustainable development of Taihu Basin. All basin stakeholders could not make an agreement on pollution solution. During decision-making, they insist on “gross domestic product (GDP) only” rather than a sustainable development preference. This paper establishes a new cost-risk decision-making system from the sustainable perspective. Contrary to the work carried out by others, water rather than money is taken as management cost here. With grey water footprint concept, pollution in water can be measured by converting into water. Due to emission reduction space limitation, some basin areas suffer the vicious circle of “management after pollution”. Management responsibility allocation alone cannot combat the pollution management due to the mismatch between responsibilities and reduction space, which should be optimized. Therefore, it is suggested that each agent, with the purpose of cost (water) saving, selects responsibility allocation schemes and cost allocation institutions through mutual negotiation. It is found that a grand coalition in any scheme or institution can achieve the minimum management cost, with approximately 24.05 billion m³ water being saved. In the grand coalition, Changzhou has the largest discharge reduction space with small management responsibility, so the other five cities may transfer their responsibilities to it by inside compensation. However, to achieve fairness and stability inside the grand coalition, Nash-Harsanyi institution in the Emission Sharing is the most optimized scheme, which can ensure a sustainable full-cooperative pollution management in Taihu Basin. In short, this paper provides a new decision-making plan to pollution management in Taihu Basin.