2018-12-15
Decomposition of aquatic plant litters is an important process in ecological system, which will significantly affect the water environment and internal organisms. In this study, cattail litter was added into surface flow constructed wetland (SFCW) system to utilize as the additional carbon source for denitrification process. The adding method for the litter was determined by evaluating the influence of different adding methods on the water environment (pH, dissolved oxygen) and the litter utilization efficiency. Then, the change of effluent organic concentration (total organic carbon, TOC) and nitrogen removal efficiency of the system was investigated after the litter addition, meanwhile, the microbial community change was analyzed by high-throughput sequencing. The results showed that cattail litter should be added in batches to the SFCW system with the dosage of 0.1?g?L?1 d?1, and the TN removal and loading of the system were significantly increased without obvious increase of the effluent TOC. After the litter addition, summer had higher increasing level of the denitrification efficiency of the system, which was lower in winter. This study could provide suitable method for cycling utilization of aquatic plant litters, and improve the denitrification effect of SFCW system.
text link:https://www.sciencedirect.com/science/article/pii/S0959652618327501