巢湖流域社会经济系统氮磷耦合格局及其协同减排机制

The study will depict anthropogenic nitrogen (N) and phosphorus (P) flow dynamics in Chaohu watershed, identify the key coupled flows and their main influence forces, and thus provide policy-makers suggestions on eutrophication mitigation which is caused by huge N and P emissions from socioeconomic system. Firstly, based on the stoichiometry theories, I will develop a method to characterize N and P coupling on both process and flow scales. By integrating the concept of life cycle analysis with the concept of substance flow analysis, I will provide a framework to analyze the N and P flows throughout socioeconomic system, and develop models to quantify these flows within specific human activities associated with N and/or P. I will also set up methods to test the results based on the principles of mass balance. Then we will quantify the pathways of annual anthropogenic N and P flows in Chaohu watershed from 1978 to 2020 and explore the dynamic characteristics of flow patterns. Our data will come from official statistics, field surveys, face-to-face interviews, questionnaires, and on-site environmental monitoring. Uncertainties of the model parameters and their propagations will be evaluated with Monte Carlo simulations. After that, we will select the key coupled flows according to the degrees of coupling and the interannual variations and identify the main decision factors that affect the coupling dynamics by the field survey and the face-to-face interview. Furthermore, we will examine the forces that influence these decision factors and explore how these forces work. These influence forces will include but are not limited to technologies, education, economic development level, and environmental protection requirements. We will determine the relationships among changes of key N and P flows, decision factors and influence forces and build a model to optimize the N and P flows with the objective of minimizing the N and P discharge equivalently into local environment and improving N and P use efficiencies throughout the life-cycle processes with lower operation costs. Finally, suggestions will be provided on the synergistic reduction of N and P discharge based on scenario analysis and cost-effectiveness analysis. The study will advance the understanding of human-driven coupled N and P cycles and provide a solid basis for decision-makers to develop policies for future synergistic reduction of N and P from socio-economic systems, even eutrophication mitigation strategies.

本研究以湖泊流域社会经济系统氮磷高效利用和协同减排为目标，基于生态化学计量学原理建立社会经济系统氮磷耦合表征方法；采用树形分析法梳理人类涉氮涉磷活动类型，运用物质流分析原理构建社会经济系统氮磷循环框架及流核算模型，基于质量守恒原理建立人类活动过程流核算结果校验方法；定量刻画1978-2020年间巢湖流域社会经济系统氮磷循环格局，从结构特征、时间变化、空间分布等方面分析格局演变特征，识别氮磷耦合特征显著（氮磷流强度大且耦合度高等）的人类活动及其对应的主要氮磷流，诊断各主要氮磷流的影响因素并解析其作用过程机制，厘定“涉氮涉磷活动-氮磷流-影响因素-决策因子”之间的响应关系；构建流域社会经济系统氮磷协同减排多目标决策模型，在情景分析和成本有效性分析的基础上，设计巢湖流域社会经济系统氮磷协同减排方案。该成果将为社会经济系统氮磷耦合研究提供定量化方法，为制定社会经济系统氮磷协同减排方案提供科学依据。

本研究建立了基于氮、磷流强度及其摩尔比三个维度的社会经济系统氮、磷耦合表征方法，基于人类活动过程元素质量守恒原理构建了社会经济系统氮-磷循环模型，运用该模型定量刻画了1978-2020年间巢湖流域社会经济系统氮-磷循环格局，从稳定耦合和弹性耦合两个方面阐释了氮、磷耦合机制，针对氮磷耦合特征显著的人类活动及其对应的主要氮磷流，提出了巢湖流域氮磷协同减排方案。该成果一方面为社会经济系统氮磷耦合研究提供了定量方法，另一方面为巢湖流域氮磷控制提供了协同减排方案。依托本项目共发表第一/通讯作者学术论文12篇（SCI收录期刊上8篇），其中Environmental Science & Technology上1篇、Bioresource Technology上2篇、 Resource Conservation and Recycling上1篇、 Journal of Environmental Management上1篇、 Science of Total Environment上2篇、Applied Energy上1篇、Resources, Environment and Sustainability上3篇、湖泊科学上1篇；获软件著作权2件，授权国家发明专利5件、美国专利1件、南非专利1件，其中2项专利成果实现技术转让（31万元）；制定地方标准1项，作为大会主席在南京举办The 25th International Sustainable Development Research Society（ISDRS）年会并受邀担任ISDRS理事会成员，2020年6月创办国际学术期刊Resources, Environment and Sustainability并与陈骏院士一起担任共同主编，依托本项目培养博士生15人（已毕业5人）、硕士研究生28人（已毕业16人）、博士后2名，从丹麦技术大学和清华大学分别引进特任副研究员各1名。领衔开发的物质循环过程虚拟仿真软件被教育部评为国家级一流本科生课程，领衔的环境科学教学团队被评为“江苏省青蓝工程优秀教学团队”，获2022年度高等教育（研究生）国家级教学成果奖（排名第八）、2021年度江苏省教学成果一等奖（排名第三）和2022年度宝钢优秀教师奖。