Decomposition of young water hyacinth leaves in lake water

• Published in: Hydrobiologia 1996-10, Vol.335 (1), p.33-41
• Main Authors: Gupta, M K, Shrivastava, P, Singhal, P K
• Format: Article
• Language: English
• Subjects: Eichhornia crassipes; Freshwater
• ISSN: 0018-8158; 1573-5117
• DOI: 10.1007/BF00013680

The rates of weight loss and nutrient release during the decomposition of water hyacinth Eichhornia crassipes leaves in lake water were determined under laboratory conditions. Water hyacinth leaves were decomposed solely by physical leaching during the initial 4 d phase under laboratory conditions and later by microbial processes. The largest part of weight loss and nutrient release by physical leaching occurred during the first 4 hours of incubation and then the decomposition rate declined. Leaf decay was significantly higher with microbial processes than by physical leaching. The loss in dry weight by physical leaching based on relative amounts was related inversely and based on the release of nutrients directly to the amount of leaf material in lake water. Dissolved inorganic and organic nutrients were released mainly by abiotic processes, the release being significantly higher during the initial phase compared to the later phase. Microbes utilized only a small portion of nutrients released during leaf decomposition. The percentage of various elements released from decaying leaves was in decreasing order, potassium, phosphorus, carbon, sodium and nitrogen.