Decomposition of Water Hyacinth in Agricultural Drainage Water
1981
Reddy, K. R. | Sacco, P. D.
The present study was designed to evaluate the nutrient release from decomposing water hyacinths [Eichhornia crassipes (Mart.) Solms.] in agricultural drainage water. In a laboratory incubation study, nutrient release from the decomposing water hyacinths was measured under aerobic and anaerobic conditions at varying levels of water hyacinth additions. In a field study, impact of water hyacinth die-off on drainage canal water quality was evaluated after a herbicide application. In the laboratory study, under both aerobic and anaerobic systems about 21–45% of the added N was lost resulting in low accumulation of inorganic N. At all levels of water hyacinth additions, soluble P release into the water was higher under anaerobic conditions than aerobic conditions. At the end of the 100-day decomposition, chemical oxygen demand (COD) of the water hyacinth treated water was reduced by 42–73% under aerobic conditions, and by 16 to 57% under anaerobic conditions and biological oxygen demand (BOD) of the water was reduced by about 67–85% under aerobic conditions and 20–53% under anaerobic conditions. Electrical conductivity (EC) and K, Mg, and Ca concentration of the water were not influenced by the oxygen status (aerobic or anaerobic conditions) of the water for any level of water hyacinth addition. Under field conditions, water hyacinth die off as a result of a herbicide application resulted in an increased concentration of soluble N and P in the drainage canal water.
显示更多 [+] 显示较少 [-]