Abstract:

Organic fertilizer replacing chemical fertilizer is an effective way to reduce the probability of nitrogen and phosphorus pollution and to mitigate agricultural non-point source pollution. Now, local governments in China are carrying out measures to combat the ecological pollution, but the conflicting interests among stakeholders make it difficult to achieve the desired result. Aimed at the production and circulation of fertilizers, an evolutionary game model among tripartite stakeholders was constructed in the present study, including local governments, fertilizer manufacturing enterprises and farmers, to explore the impact of initial willingness, reward and punishment policies, costs and benefits on the implementation efficiency of the organic fertilizer replacing chemical fertilizer policy from the perspective of market supply and demand, and then to propose multi-subject collaborative governance paths of agricultural non-point source pollution. It was shown that there were three stable strategies of the model, including (loose supervising, not producing commercial organic fertilizers, not replacing chemical fertilizers), (loose supervising, producing commercial organic fertilizers, replacing chemical fertilizers), and (strict supervising, not producing commercial organic fertilizers, not replacing chemical fertilizers). The profitability of organic fertilizers was the key to get (loose supervising, producing commercial organic fertilizers, replacing chemical fertilizers). The balance of supply and demand in the fertilizer market was the essence for achieving game equilibrium, and the initial willingness of enterprises had a greater guiding effect on the result than that of farmers. The decision-making process of tripartite stakeholders was interest-oriented. Therefore, within the scope of financial support, increasing incentives and penalties could improve the willingness of enterprises and farmers to produce and apply organic fertilizers. Thus, it is suggested that the local governments should take economic benefits as the promotion guide and build up a long-term mechanism for collaborative management through strengthening environmental education and promotion, formulating economic policies rationally, and building technological cooperation platforms.

Key words: agricultural non-point source pollution, organic fertilizer replacing chemical fertilizer, collaborative governance, evolutionary game