pH和温度对薏苡植物床去除富营养化水中氮磷的影响

The Effects of pH and Temperature on Removal of Nitrogen and Phosphorus from Eutrophicated Water by Coix Lachryma-jobi.L

采用模拟试验研究了pH和温度对薏苡植物床去除人工模拟富营养化水中氮磷的影响。一组试验在保持不同温度下即10℃、20℃、30℃,另一组试验每2d调节一次pH使其分别保持在4、5、6、7、8、9。结果表明,薏苡植物床对富营养化水中氮磷的去除十分有效,其中在pH4和pH5条件下对总氮的去除率可达到77.75%和78.30%,总磷的去除率达到70.02%和73.52%,高于其他的pH条件;温度为30℃时对氮磷的去除效果要远远好于10℃和20℃。这些结果表明较低pH和较高温度有利于薏苡植物床对水体氮磷的去除,这种植物可作为夏秋季富营养化水体修复的候选植物。

The effects of pH and temperature on removal of nitrogen and phosphorus from eutrophicated water by Coix Lacryma-job were studied by simulation experiments. In one experiment, Lachryma-jobi. L was grown under different temperatures, that is 10 ℃, 20 ℃, 30 ℃ ; in the other experiment, the plants were grown in eutrophicated water with different pH of 4, 5, 6, 7, 8, and 9, respectively. The results from pH effect experiment showed that the removal rate of total nitrogen reached 77.75% and 78.30% and that of total phosphorus reached to 70.02% and 73.52% at pH 4 and 5. And the removal rates of nitrogen and phosphorus at other pH values were lower. From the temperature experiment, we could see that the removal rates of nitrogen and phosphorus under 30 ℃ were much higher than those under 20 ℃ andl0 ℃. These results indicated that more efficient removal of N and P by Coix lacryma-job occur at relative low pH and high temperature, and this plant can be used for phytoremediation of eutrophic water at summer and autumn.