生活垃圾分类回收是解决“垃圾围城”困境，促进“城市矿产”开发的有效途径。城市生活垃圾分类回收系统包含居民、企业和政府等多个主体，且主体间的相互作用机制较为复杂。目前，我国生活垃圾分类回收管理效果欠佳，政府在制定政策时缺乏对各利益相关主体的综合考虑。面对各地成功的管理政策方案，由于地区差异存在，需对实施效果进行预判。因此，研究城市生活垃圾分类回收系统中各主体的行为决策因子和交互作用机制，系统评估预判政策实施效果以选择有效的管理方案，是城市生活垃圾分类回收管理中的两个关键问题。本文首先通过对居民生活垃圾处理行为的社会调查，运用结构方程统计分析和离散选择模型方法，构建了居民垃圾处理行为决策模型；构建了企业主体行为决策利润函数，探讨了分类回收系统中各主体行为交互作用机制。在此基础上，采用多主体仿真建模方法，开发了城市生活垃圾分类回收系统多主体行为模拟模型，用以模拟政策刺激加入后系统中居民、资源回收企业、环卫企业等微观主体的行为响应和系统宏观演化过程；运用开发的模型对生活垃圾计量收费、增加宣传教育渠道、资源回收补贴和新型回收模式推广等政策的实施效果进行了预测模拟和定量化评价。研究发现，居民垃圾处理行为选择是4个主观因素和7个外部因素共同作用的结果，且外部因素对居民垃圾处理行为的综合影响是个体主观因素的近2倍。比较分析五种政策的实施效果表明：垃圾计量收费、资源回收补贴和增加宣传教育渠道三种政策组合实施，可有效调控居民、再生资源回收企业等微观主体行为，使得宏观系统涌现最优；情景模拟一年后，“不分类”居民由185万人减少到25万人，减少86%，“分类投放”居民由128万人减少到108万人，减少约16%，“分类交售”居民由105万人增长到281万人，增加约63%；人均垃圾日产生量由1.21 kg下降到1.04 kg，实现垃圾减量14%；资源回收率由33.4% 增加到66.5%。其他四种政策的实施效果比较排序为：新型回收模式推广情景 > 计量收费情景 > 资源回收补贴情景 > 增加宣传教育渠道情景。对居民主体实施垃圾计量收费、对回收企业主体给予资源回收补贴的经济激励政策，可有效促进两类主体形成良性互动。同时，建议加强城市分类回收配套设施规划建设，开展垃圾分类与资源回收系统融合发展，并因地制宜地推广新型回收模式。
Classification and resource recycling of urban household solid waste (HSW) is an effective way to solve the social dilemma of “garbage-sieged city” and promote the exploitation of “urban mineral resources”. The classification and recycling of the HSW is a complex system and comprised of several principal agents, including residents, enterprises and the government and so on, and their interactions are also influential and inevitable. Currently, the management of the classification and recycling of the HSW in China is ineffective in that the government has not comprehensively considered the interests of each involved agent when formulating relevant policies. In the presence of the success of the policy implementation nationwide and the existence of regional disparities, there should be a prediction made for the evaluation of the implementation effects. Therefore, the decision making in the management of the HSW would lie in two crucial elements, namely behavioral decisions and interactions between each main agent in the system and effective management policies selected for the evaluation of the implementation effects.In this paper, the decision making model for residents' garbage disposal behavior is constructed by by means of social investigations, structural equation modeling (SEM) and discrete selection modeling, and the decision making models for enterprise agents are proposed based on benefit maximization theory. Meanwhile, the mechanism of interactions between main agents in the HSW classification and recycling system is discussed. Based on the above research, one multi-agent based behavior simulation model has been developed for the classification and recycling of the HSW using multi-agent based simulation and modeling (MABMS) technique, which can simulate micro behavioral responses of each agent and macro evolution process of the system. Furthermore, by using this designed model, we have conducted a quantitative evaluation on the implementation effects of the metering charge of the HSW, subsidies of the recycling, improved education program and promotion of new designed recycling models.It is found that the behavioral selection has been closely related to four subjective factors and seven external factors and the combined effects of the latter ones is nearly two times that of the individual subjective factors. The results of the comparative analysis on the implementation effects of five policies have illustrated that three policies combination of the waste metering charge, recycling subsides and enhanced promotion devices can effectively regulate the micro behavior of the residents and resource recycling enterprises and optimize the macro system meanwhile. One year after the implementation of the simulation, the number of “unclassification” residents has dropped from 1.85 million to 250 thousand decreased by 86%; the number of “classification” residents has declined from 1.28 million to 1.08 million, reduced by 16%; the number of “classification and selling” residents has risen from 1.05 million to 2.81 million, increased by 63%; the daily waste output per capita has decreased from 1.21 kg to 1.04 kg, reduced by 14%; the recovery rate of resources has been raised from 33.4% to 66.5%. The implementation effects of the other four policy scenarios have been ranked as follows: the new designed recycling model promotion > the metering charge > the recycling subsides > the enhanced education program. Concerning the metering charge and the recycling subsidies, they can benefic positive interactions encouraged by such economic stimulus. At the same time, it is suggested to strengthen the planning and construction of supporting facilities for urban classification and recycling, to push forward the integration of the classification and recycling of the HSW, and to promote the new recycling mode according to local conditions.
