Potential removal of particulate matter and nitrogen through roots of water hyacinth in a tropical natural wetland.

摘要

A natural shallow, eutrophicated wetland receiving an influx of domestic sewage and agricultural run-off, heavily infested with water hyacinth (Eichhornia crassipes), and located in Ujjain city, Madhya Pradesh, was studied to determine the role of water hyacinth in the removal of particulate matter attached to the root system and nitrogen as contained in the roots attached to particulate matter (RAPM) and in plant tissues. The recorded water hyacinth density was 79 plants/m2, with 1.549 kg dry plant tissue, which adsorbed 663 g RAPM (about 42% of dry plant tissue), thus potentially removing it upon the mechanical harvest of the plants. In addition to the significant amount of RAPM, water hyacinth harvesting also brought about removal of 1.396 g/m2of organic matter, 0.536 g of total nitrogen, 0.482 g of ammoniacal nitrogen, and 0.338 g of nitrate nitrogen. This amounted to nitrogen removal of 37.32 kg/ha through the plant tissue + 5.36 kg nitrogen/ha in the RAPM, besides 6630 kg/ha of particulatematter through RAPM.