黑臭水体治理中水生植物腐解特征及水环境影响效应研究

Study on the Decomposition Characteristics of Aquatic Plants and Their Effects on Water Environment in the Treatment of Black and Odorous Water

为研究黑臭水体治理中水生植物腐解特征及水环境影响效应,选取湿地生态系统常见4种水生植物,分析了不同残体腐解周期内营养物的动态迁移规律。在整个试验周期内,各试验组有机质、氮磷营养盐变化趋势相似,最终腐解率存在差异,依次为苦草(51.86%)>菖蒲(29.73%)>美人蕉(26.51%)>芦苇(25.32%)。各试验组水质指标COD、TN和TP浓度均在试验前中期上升,中后期持续下降,腐解结束时高于CK组。Pearson相关性和显著性分析发现,黑臭水环境中残体初始组分含量是影响腐解的重要因素,难溶物含量与最终腐解率显著负相关(P<0.05)。试验结果表明:水生植物腐解对黑臭水体水质、气体环境都会产生较大影响,应在植物腐解前中期进行有效治理,避免加剧水质恶化。

In order to study the decomposition characteristics of aquatic plants and their effects on water environment in the treatment of black and odorous water,four aquatic plants(reed,bitter grass,calamus and canna)were selected to analyze rsidues nutrients dynamic migration processes.The results showed that the changes of organic matter,nitrogen,phosphorus and nutrients in the decomposition processes of four aquatic plants were similar,but the rates were different.At the end of the experiment,the decomposition rates of the four plants were as follows:bitter grass(51.86%)>calamus(29.73%)>canna(26.51%)>reed(25.32%).COD,TN and TP concentrations of test groups all increased in the early and middle stages of the experiment,and then decreased.At the end of the decomposition,water quality indicators of the test groups all were higher than the CK group.Pearson correlation and significance analysis showed that the initial component content in the black odor water environment is an important factor that affects the decomposition,and the insoluble matter contents had a significant negative correlation with the decomposition rates(P<0.05).The results show that the decomposition of aquatic plants will have a significant impact on the water quality and gas environment in black and odorous water.Effective treatment should be carried out in the early and middle stages of plant decomposition to avoid worsening the water quality.