凤眼莲腐烂分解对湖泊水质的影响

 在南京莫愁湖生态工程围区内,将凤眼莲(EichhorniacrassipesSolms)压入水下,待其自然腐烂分解,跟踪监测水质变化情况,研究凤眼莲腐烂分解对湖泊水质的影响.结果表明,初冬压入水下的凤眼莲到次年3月中旬左右开始腐烂并对湖泊水体产生一定污染,4月中旬左右达到高峰,到5月中旬左右污染影响明显下降.水质变化呈抛物线状,可划分为4个阶段.由于残体释放量与水体自净力之间存在此消彼长的关系,提高湖泊水体自净能力是降低冬季水生植物死亡污染水体的关键所在.

Effect of Eichhornia craeripes Solms (ECS) decomposing on water quality of lakes

In the ecological engineering enclosure of Nanjing Mochou Lake, ECS was pressed into water to make it decomposing naturally, then the status of water quality change was monitored following the tracks to study the effect of the decomposition on the water quality. ESC pressed into water in early winter began to decompose in the middle ten days of March of next year and polluted definitely the lake water; and reached the peak in the middle ten days of April with marked decrease of pollution effect about middle ten days of May. The process of ECS death decomposition was water pollution through its residual decomposition and lake self-purification ability to purify the waters. The water quality change presented parabola form which could be divided into four steps. Enhancing the self-purifying ability of lake waters was the key for decreasing the water pollution by the death of the hydrophyte in winter.