Influential factors affecting the generation of kitchen solid waste in Shanghai, China

The influential factors of the generation of kitchen solid waste (KSW) are vital to design policies that target effective KSW reductions and achieve sustainable KSW management, but has not been extensively studied. The study aims at the first step of KSW management only, i.e., generation, which is the first KSW analysis survey in Shanghai to comprehensively investigate the characteristics and influential factors of KSW generation (KSWG). The data were collected from August to October 2019, which resulted in a total of 433 usable questionnaires regarding KSWG in Shanghai, China. The average rate of KSWG is 6.038 kg/household/week or 0.265 kg/person/day. The average per-person number of KSWG bags is 0.295. The regression results show that the characteristics of KSWG are related to household size, household income, the habit of ordering takeout, district of residence, and meticulous consumption culture. Some interesting findings are observed in the present study. Firstly, there is a nonlinear relationship between KSWG and household size, which can be explained by "common consumption". Secondly, there is a nonlinear relationship between KSWG and household income, which can be explained by the Engel coefficient, which also provides supporting evidence for the environmental Kuznets curve (EKC) hypothesis. Finally, the habit of ordering takeout, district of residence, and meticulous consumption culture are all influential factors of KSWG. The results of the study can improve public awareness and knowledge of KSWG, and suggestions on the minimization of KSWG are put forward, thus will serve as a new reference for the sustainable KSW management of other cities, especially cities in developing countries.Implications: In the practice of sustainable waste management, KSWG is a complex issue that requires a broad analytic approach that considers several factors simultaneously. From a practical perspective, policy decision-makers should pay attention to at least four important actions to reduce KSWG: Firstly, compared with urban areas, rural areas are important areas for reducing KSWG, which should be given sufficient attention. Secondly, compared with low-income households, high-income households are the focus of KSWG reduction and should be considered. Thirdly, meticulous consumption culture plays an important role in promoting the reduction of KSWG, and this culture should be promoted and cultivated in the formulation of actual waste management policies. This is also an important way to reduce KSWG and should be fully considered. Finally, in the pilot process of domestic waste separation in Chinese cities, 3 R (Reduce, Reuse, and Recycle) waste management concept and method in circular economy can be applied to KSW treatment, and adequate financial support is necessary. Through strengthening the management of KSW, the potential value of KSW can be further developed, so as to realize KSWG reduction and resource utilization.