Abstract: The Peiyang Park campus of Tianjin University is a pilot project of sponge campus construction. This paper focuses on the pollutants variation of the water and sediments in a artificial water system in the Peiyang Park campus, and the pollutants correlation between water and sediments are also analyzed by examining the correlation coefficients and multiple regression determination coefficients of the monitoring data. The results show that the water pollutants concentration are mainly determined by pollution sources and water mobility, with a low level observed in summer and a high level in winter. Most of the monitored water contaminants are nitrogen (total nitrogen from grade IV to worse than grade V and ammonia nitrogen from grade III to V) and chemical oxygen demand (COD from grade IV to worse than grade V). The sediment contaminants have no significant seasonal concentration fluctuation observed in this study, and their major components are nitrogen (total nitrogen content of 0.1-17.1 mg/kg and ammonia nitrogen content of 0.6-4.7 mg/kg) and chemical oxygen demand (COD content of 26.9-190.4 mg/kg). In addition, the sum of the determination coefficients of contaminant concentration in water and sediment is larger or smaller than the coefficient of the whole water system (i.e. contaminant concentration of water plus contaminant concentration of sediment). This indicates that the contaminants in the man-made water system are affected by the water and sediment together and significant correlations exist between the water contaminants and sediment contaminants.

Key words: sponge campus, man-made water system, water quality, sediment, correlation