RBF_NH4+
The 20-month sand column experiment was divided into three stages according to influent columns type and experimental purposes, i.e. 1 6-month microbial cultivation, surface water (SW) used as influents for CBlank(C5), CCtrl(C7/8), and CTret(C9/10); 2 6-month NH4+-N adaptation, SW used as influents for CBlank and CCtrl, SW + NH4+-N (2 mg/L) used as influents for CTret; 3 8-month OMP exposure experiment, SW used as influents for CBlank, SW + 128 OMPs (100 ng/L of each) used as influents for CCtrl, SW with the addition of 128 OMPs (100 ng/L of each), and NH4+-N (2 mg/L) used as influents for CTret.