| 生态沟渠-生物滞留池组合控制农村径流污染 |
| 摘要点击 1489 全文点击 480 投稿时间：2021-08-10 修订日期：2021-10-05 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 生态沟渠 生物滞留池 农村径流污染 载体碳源 干湿交替 |
| 英文关键词 ecological ditch bioretention pond rural runoff pollution carrier carbon source alternating wet and dry period |
|
| 中文摘要 |
| 生态沟渠和生物滞留池因其良好的径流污染控制能力和生态效益，日益受到广泛关注和应用，但单一的生态沟渠或生物滞留池在农村径流污染控制中常存在氮磷去除效果不稳定和基质易堵塞等问题.将两者串联构建组合系统，利用生态沟渠预处理去除部分污染物，可降低生物滞留池污染负荷和减轻基质堵塞；同时在生物滞留池中设置淹没区并添加天然载体碳源提升系统脱氮效果.研究了载体碳源、降雨强度和干湿交替等条件对生态沟渠-生物滞留池组合系统控制农村径流污染的影响.结果表明，投加稻草和木屑两种天然载体碳源分别将生物滞留池段的TN去除率提升19.9%和20.4%.模拟降雨强度从小雨增至大雨时，外加碳源组合系统COD、NH4+-N、TN和TP去除率平均下降17.0%、16.8%、20.4%和17.2%，其中生态沟渠段对4种污染物的去除贡献平均降低16.3%、13.0%、24.2%和22.1%.干湿交替运行可提高系统的污染物去除效果，相较连续进水，干旱3周后木屑组TN平均去除率提升12.3%.微生物群落分析结果显示，木屑组和稻草组生物滞留池样品的α多样性高于对照组；投加载体碳源的生物滞留池淹没区中硫杆菌属（Thiobacillus）丰度显著高于对照组.研究结果有望为组合系统在实际工程中的应用提供技术支撑. |
| 英文摘要 |
| Ecological ditches and bioretention ponds have received widespread attention and application due to their runoff pollution control capabilities and ecological benefits. However, a single ecological ditch or bioretention pond often has problems, such as unstable nitrogen and phosphorus removal and substrate clogging in rural runoff pollution control. Thus, we connected the two facilities in a series to construct a combined system, using the ecological ditch to pretreat, therefore reducing the pollution load of the bioretention pond and mitigating substrate clogging. At the same time, the submerged area was set and an external natural carrier carbon source was added in the bioretention pond to improve the nitrogen removal. The effects of the carrier carbon source, rainfall intensity, and alternating wet and dry conditions on the control of rural runoff pollution by the combined system were explored. The results showed that adding straw and sawdust as carrier carbon sources could increase the TN removal of the bioretention pond by 19.9% and 20.4%, respectively. When the simulated rainfall intensity increased from light rain to heavy rain, the removal efficiencies of COD, NH4+-N, TN, and TP in the combined system with external carbon source decreased by 17.0%, 16.8%, 20.4%, and 17.2% on average, respectively. The contribution of the ecological ditch to the removal of the four pollutants decreased by 16.3%, 13.0%, 24.2%, and 22.1% on average. Alternating dry and wet operation can improve the pollutant removal. Compared with continuous inflow, the average TN removal of the sawdust group increased by 12.3% after three weeks of drought. The results of microbial community analysis showed that the α-diversity of the bioretention pond in the sawdust group and the straw group was higher than that in control group. The abundance of Thiobacillus was significantly higher in the submerged area of bioretention ponds with carbon sources than that in the control group. These research results are expected to provide technical support for the practical application of the combined system. |
|
|
|
