Strong correlation existed between ROL and nitrogen removal rates, but weaker correlations were found between ROL and
removal rates of other nutrients (Table 2). Correlations between ROL and nutrient removal rates were stronger in C. flabelliformis
wetland than in the other wetlands. Significant correlation between ROL and photosynthetic rate was tested in C.
flabelliformis wetland. There was no significant correlation between ROL and root activity in all the wetlands