Effect of Decomposition of Submerged Plants（Vallisneria natans）on Water Quality
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
7 7
Page:
60-67
Column:
Date of publication:
2020-04-01
- Keywords:
- decomposition of? Vallisneria natans ; water quality; high purity water; sediment suspension; mass loss rate; nutrients
- Abstract:
- Submerged plants can effectively control lake eutrophication, but the effects of their periodic decay on lake ecosystems in different water environments can not be ignored. An indoor decay simulation experiment of? Vallisneria natans was carried out for 66 days by using the mesh bag method. The decomposition process and variations in concentration of nitrogen, phosphorus and other nutrients in water under different biomass densities in high purity water and sediment suspension were explored. The decomposition process of? Vallisneria natans with different biomass densities (0.1 g/L, 0.2 g/L and 0.4 g/L) could be divided into two stages including rapid leaching and slow decomposition, and the mass loss rate of each biomass density group in different stages was different, but the overall trend was consistent. In high purity water environment, the nutrient content (COD, TP) of water was positively correlated with biomass (r=0.478 and 0.697, P<0.05). 0.4 g/L of? Vallisneria natans would significantly increase the content of nutrients and destroy the water quality. When it was decomposed, the mineralization rate of phosphorus was faster than that of nitrogen. Under the environment of sediment suspension, the effect of decomposition of? Vallisneria natans on water quality had obvious timeliness and stage difference. TN concentration was significantly positively correlated with DO and pH (r=0.839 and 0.806, P<0.05). Complex adsorption and degradation reactions of nitrogen, phosphorus and other nutrients released by the decomposition of? Vallisneria natans took place at the sediment water interface, and a proper amount of Vallisneria natans could promote the migration and transformation of nitrogen and phosphorus in various forms.
Last Update:
2020-04-01