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Seeing that Shanghai implemented mandatory household waste sorting system (referred as Shanghai Model) in 2019 and achieved remarkable improvements, the study focuses on how to localize it in second-tier cities. Specifically, by applying system dynamics method, a qualitative Basic Model and a quantitative Shanghai Model simulating residents' waste related behavior are built. Combined Theory of Planned Behavior and the Split-Core Model are adopted. Data of Zhengzhou is inputted and simulated to representatively deliver policy implications to second-tier cities. The result shows that improving transactional context can lift the weight of willingness and depress the weight of opportunism in behavior decision makings. Shanghai Model significantly improves the legal transaction context of waste sorting which make residents actively sort the wastes under the promotion of willingness. For second-tier cities of China, improving transactional context to reduce opportunism and conquering the short board of willingness to promote active participation are indispensable. And, waste reducing measures like the unit pricing system are recommended to make up the shortage of the Shanghai Model. The study puts forward a synthetic analyzing framework of waste related behaviors and builds a portable policy analyzing system of waste management for both China and other developing countries. • Basic model combing Theory of Planned Behavior and Split-Core Model is built. • Waste generation, reducing, recycling, and sorting system dynamics model is built. • Shanghai Model can improve household waste sorting and recycling. • Zhengzhou is recommended to improve facility level before adopting Shanghai Model. • The study provides a policy making tool for household waste management. [ABSTRACT FROM AUTHOR]

• Models for household recycling behaviour in high-rise buildings were evaluated. • The used of recycling facilities can be predicted by physical setting. • The use of informal recycling sectors can be predicted by housing type. • Implications for public design in high-density residential areas are provided. • It provides insights into public design in high-rise residential areas. Recycling strategies and waste management for the source separation of recyclables are still in their infancy in China and many other developing countries. Unlike formal recycling systems with strictly regulated management in high-income countries, waste management and recycling activities in low-income and middle-income countries are predominantly informal. Formal recycling systems often have very small amounts of recyclables in comparison to informal recycling systems. Considering the Chinese case of urban Guangzhou, where formal and informal recycling systems coexist, this study investigated household recycling behaviour and explored the sociodemographic and contextual factors that affect this behaviour. Based on data collected through questionnaire surveys and interviews, a model of the use of public recycling facilities (UPRF) and a model of the use of informal recycling sectors (UIRS) were evaluated using correlations and multiple regression analyses. The findings indicated that the use of public recycling facilities can be significantly predicted by the launch of a source separation scheme, the physical setting and satisfaction with public recycling facilities. The sociodemographic variables did not significantly predict the use of public recycling facilities but did significantly predict the use of informal recycling sectors. This study's findings have implications for researchers and policymakers and shed light on public designs for sustainability. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are widely detected in wetlands as emerging pollutants of global concern. Co-occurrence of MPs and trace metals in wetlands is common and the vector effects of MPs on other environmental pollutants have been increasingly reported. However, the interaction of different MPs and trace metals under environmentally realistic conditions is not well understood. Here, we investigated the adsorption capacity of MPs for metals under simulated conditions of Poyang Lake wetlands in Jiang Xi, China, a Ramsar site of international importance for conservation and sustainable use. ICP-MS was used to quantify the amount of adsorbed metals onto different types of MPs. SEM-EDS and micro-FTIR were used to examine the morphological and chemical characteristics of MPs before and after metal adsorption. The influence of internal (polymer types and particle sizes of MPs) and external factors (water pH values, organic matters, ion strength, and sediment) on metal adsorption was systematically investigated. Metal adsorption equilibrium was most achieved at 72 h. The adsorption capacity of MP types to metal ions tended to decrease as PP > PE > PS, and the amount of adsorbed metals decreased as Cu > Pb > Cd. The amount of adsorbed metals generally decreased with the increase of particle size of MPs. With the increase of water pH and K+ strength, the adsorption of metals by MPs showed an increasing and then decreasing trend; the adsorption capacity of MPs increased with the increase of fulvic acid. Under the simulated sedimentary conditions, the adsorption of different metals by MPs also tended to be Cu > Pb > Cd, which was mainly determined by metal concentrations in the sediments collected in situ. The results of this study improve our understanding of metal-MP interaction under simulated environmental conditions, shedding new light on the environmental behavior of MPs and metals in wetlands. [Display omitted] • Metal adsorption by MPs is studied under simulated Poyang Lake wetland conditions. • Particle size and polymer type of MPs significantly affect metal adsorption. • PP MPs show higher adsorption capacity for metals than PE and PS MPs. • Water pH, ionic strength, organic matter, and sediment influence metal adsorption. • The knowledge of metal-MPs interaction in natural wetlands is still limited. [ABSTRACT FROM AUTHOR]