Based on the laboratory and simulation experiments, Guo Changcheng and his group proved that the
potamogeton had good purification effect for the polluted river water from the sewage of inferior Ⅴ class
mainly in the dry fall and winter. Tong Changhua used aquatic plants to control the pollution of
eutrophicated water [13]. The results showed that aquatic plants had a higher ability to remove TN, TP
and nitrate nitrogen. Among them, foxtail alga and grain leaf pondweed could effectively remove TN
(83.84% and 77.54%), TP (91.3%) and nitrate nitrogen (95.85% and 90.65%), but had no significant
effect on removing ammonia nitrogen (only 14% to 70%).