渤公岛水生植物-微生物系统水质净化效应研究

Study on the effect of aquatic macrophytes-microorganism system on purifying water of BoGong Island

目前,由氮、磷等营养盐所引起的湖泊富营养化已成为世界性的环境问题。如何有效利用水生植物-微生物系统去除氮、磷具有非常重要的意义。本实验通过对渤公岛某河段水质和细菌总数的监测,以及对其水生植物荇菜、菹草、着生藻的盖度的统计,来分析其水质动态变化规律,以及水质参数、细菌总数、水生植物盖度之间的相关关系。实验分析得出:总磷(TP)是细菌生长的限制因子。水生植物荇菜吸收氨氮(NH4+-N)的效果比较好,而且促进了细菌的生长;菹草生长时对水体中TP的吸收效果比较好。同时,大量收割衰老菹草也是降低水体营养水平的重要手段。因而研究荇菜、菹草对水体污染的改善作用显得尤为重要,也具有现实的应用价值。而着生藻在生长时可以大量吸收氮、磷等营养盐,但也抑制了微生物的生长,不利于营养盐的分解,抑制了其它水生植物的吸收。因而利用水生植物和藻类富集氮、磷是治理、调节和抑制湖泊富营养化的有效途径。

In the present, eutrophication of lakes induced by nutrient of nitrogen and phosphorus becomes most environmental problem in the world. How to effectively use macrophytes-microorganism system to purify water is very important. In the experiment, nutrient and total number of bacteria in the reach of BoGong Island were measured, and quantity plants of Potamogeton crispus, Nymphoides pehatum and algae in sampling spots were estimated. With these data, change rules of nutrient in waterbody and correlativity of them were analyzed. The resuhs showed that TP was the limitation factor of bacteria; the effect of Nymphoides pehatum absorbing NH4^＋-N was preferably, and this plant promoted the growth of bacteria; the effect of Potamogeton crispus in the growth period absorbing TP was preferably. Moreover, harvesting Potamogeton crispus was also an important way of decreasing nutrient level of waterbody. Algae could absorb a great deal of nutrient when it grew, but it also restrained growth of microorganism and decomposition of nutrient. As a resuh, use macrophytes and algae enrich nutrient is effective to government, adjust and control lake eutrophication.