Adding siderophores: A new strategy to reduce greenhouse gas emissions in composting.

Microbial community is the primary driver causing the greenhouse gas emissions in composting. Thus, regulating the microbial communities is a strategy to reduce them. Here, two different siderophores (enterobactin and putrebactin) were added, which could bind and translocate iron by specific microbes, to regulate the composting communities. The results showed that adding enterobactin enriched Acinetobacter and Bacillus with specific receptors by 6.84-fold and 6.78-fold. It promoted carbohydrate degradation and amino acid metabolism. This resulted in a 1.28-fold increase in humic acid content, as well as a 14.02% and 18.27% decrease in CO2 and CH4 emissions, respectively. Meanwhile, adding putrebactin boosted the microbial diversity by 1.21-fold and enhanced potential microbial interactions by 1.76-fold. The attenuated denitrification process led to a 1.51-fold increase in the total nitrogen content and a 27.47% reduction in N2O emissions. Overall, adding siderophores is an efficient strategy to reduce greenhouse gas emissions and promote the compost quality.

Study on the relationship between crisis awareness and medical waste separation behavior shown by residents during the COVID-19 epidemic.

Specific awareness is an important factor that affects individual behavioral decisions. This study explored the relationship between crisis awareness and medical waste separation behavior shown by urban residents during the COVID-19 epidemic in China. The results of a questionnaire survey data (N = 668) were subjected to statistical analyses, regression analyses, and cross-analyses. In terms of medical waste separation, the detection rate was 12.65%, among which, the waste separation behavior by citizens was the highest (24.56%). In terms of the relationship between crisis awareness and medical waste separation behavior, the crisis awareness generated by the environmental situation is significantly related to individuals' participation in the separation of medical waste. In particular, individual spontaneous crisis awareness only had a significant positive correlation with the waste separation behavior for the decision factor. The residents were clustered into "sensitive", "conscious", "passive", and "insensitive" types based on the original crisis awareness characteristics. The "sensitive" group was more actively involved in the separation of medical waste, while the "insensitive" group showed the worst performance for the separation of medical waste. A comparison of the separation behaviors shown by the "conscious" group and the "passive" group confirmed that environment-driven crisis awareness has a higher correlation with the separation of medical waste by residents.