植被浅沟运行效果评价及改进设计研究
发布时间：2018-09-08 14:36
【摘要】：植被浅沟是低影响开发技术中一种良好的生态排水设施，，能够有效削减径流中的污染物含量，同时起到削减峰值流量和调控径流总量的作用。雨量和雨强是影响植被浅沟运行效果的重要因素，但目前的研究结论并未按上述因素对植被浅沟进行效果进行划分。且与传统排水管道相比，植被浅沟占地面积略大，同时还面临着重金属等污染物的积累和溶出风险问题，这也限制了其在城市高密度地区的推广。 本研究针对上述问题，在全面了解国内外研究现状的基础上，对暴雨情况下植被浅沟的运行效果进行了评析，同时利用International Stormwater Best Management PracticesDatabase中所积累的植被浅沟多年运行数据进行了统计分析，并从统计分析和实地监测两方面对植被浅沟内污染物变化规律进行了分析。通过加设渗排管及减小种植土厚度对传输型植被浅沟进行了改良，并分析了堰板和植物型消能坝对其去除效果的影响。考察了深圳牛山公园植被浅沟内种植土污染物的积累状况，并估算了其运行寿命。 主要研究内容和结果如下： （1）与小降雨事件相比，传输型植被浅沟在暴雨条件下的污染物去除效果及稳定性均有所降低，对SS的平均去除效果仅为10%，且硝酸盐有明显的溶出现象，对径流峰值和总量的削减效果也显著下降。 （2）统计分析的结果表明植被浅沟并非对所有污染物的去除效果都与入水浓度相关，其中浅沟对NO3-、TOC、细菌、As及Ni的去除效果与入水浓度均无明显相关性，对TKN的去除效果还与降雨历时和降雨量相关。随着降雨量的增加，植被浅沟对径流的削减效果逐渐降低，当降雨量大于45mm时，植被浅沟很难体现出良好径流削减效果。 （3）植被浅沟对TP、NH4+、COD及SS的去除效果随植被浅沟长度的变化关系符合指数衰减模型，但在不同进水浓度下，其系数有所变化，植被浅沟对NO3-的去除效果不符合该规律。 （4）加装渗排管后植被浅沟的污染物去除效果显著提升，加装堰板后植被浅沟的滞留能力显著提升，但是依然不能有效防止小粒径（40微米）颗粒的再悬浮；与堰板相比，植物型消能坝能够显著控制细小颗粒物的再悬浮。 （5）牛山公园内植被浅沟种植土的特性与周边土壤相比已经发生了显著地变化，其中种植土有机质含量总体上呈降低趋势，且pH在起始端较低，重金属含量略有增高，但仍保持在良好范围内，通过估算，牛山公园内植被浅沟仍可以能够有效运行39年而不超过土壤规范中的含量限值，其中Zn的积累是制约植被浅沟运行寿命的最主要的因素。
[Abstract]:Vegetation shallow gully is a good ecological drainage facility in low-impact development technology, which can effectively reduce pollutant content in runoff, reduce peak discharge and control total runoff. Rainfall and rainfall intensity are important factors affecting the operation effect of vegetation shallow gully, but the current research conclusions do not follow the above factors on vegetation. Compared with the traditional drainage pipeline, the shallow vegetation ditch covers a slightly larger area, and also faces the risk of accumulation and dissolution of heavy metals and other pollutants, which also limits its application in high-density urban areas.
In view of the above-mentioned problems, on the basis of a comprehensive understanding of the research status at home and abroad, the operation effect of shallow vegetation ditches under rainstorm conditions was evaluated and analyzed. At the same time, the operation data of shallow vegetation ditches accumulated in the International Stormwater Best Management Practices Database for many years were used for statistical analysis and practice. The change of pollutants in shallow vegetation ditches was analyzed from two aspects of ground monitoring. The transport vegetation ditches were improved by adding seepage drainage pipes and reducing planting soil thickness. The effects of weir plates and Plant-type energy dissipation dams on their removal efficiency were analyzed. The accumulation of pollutants in planting soil in shallow vegetation ditches of Niushan Park in Shenzhen was investigated. The operating life is estimated.
The main research contents and results are as follows:
(1) Compared with small rainfall events, the removal efficiency and stability of pollutants in shallow ditches with transported vegetation were reduced, and the average removal efficiency of SS was only 10%. Nitrate dissolved obviously, and the reduction effect of peak runoff and total runoff was also decreased significantly.
(2) Statistical analysis showed that the removal effect of shallow vegetation ditch was not correlated with the influent concentration. The removal effect of shallow vegetation ditch on NO3-, TOC, bacteria, As and Ni was not correlated with the influent concentration. The removal effect of TKN was also correlated with rainfall duration and rainfall. When the rainfall is more than 45 mm, it is difficult for shallow vegetation gully to show good effect of runoff reduction.
(3) The relationship between the removal efficiency of TP, NH4+, COD and SS by shallow vegetation ditch and the length of shallow vegetation ditch conforms to the exponential attenuation model, but the coefficient varies with different influent concentration, and the removal efficiency of NO3 - by shallow vegetation ditch does not conform to the law.
(4) The removal efficiency of pollutants in shallow vegetation ditches was significantly improved after adding seepage drainage pipes, and the retention capacity of shallow vegetation ditches was significantly improved after adding weir plates, but the resuspension of small-sized particles (40 microns) could not be effectively prevented. Compared with weir plates, plant-type energy dissipation dams could significantly control the resuspension of fine particles.
(5) Compared with the surrounding soil, the characteristics of planting soil in the shallow vegetation ditch in Niushan Park have changed significantly. The organic matter content in the planting soil is generally decreasing, and the pH value is lower at the beginning, and the heavy metal content is slightly increased, but it is still in a good range. By estimating, the shallow vegetation ditch in Niushan Park can still be effective. Zn accumulation is the most important factor restricting the life span of shallow furrow vegetation.
【学位授予单位】：北京建筑大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV213.9;TU992
本文编号：2230811
[Abstract]:Vegetation shallow gully is a good ecological drainage facility in low-impact development technology, which can effectively reduce pollutant content in runoff, reduce peak discharge and control total runoff. Rainfall and rainfall intensity are important factors affecting the operation effect of vegetation shallow gully, but the current research conclusions do not follow the above factors on vegetation. Compared with the traditional drainage pipeline, the shallow vegetation ditch covers a slightly larger area, and also faces the risk of accumulation and dissolution of heavy metals and other pollutants, which also limits its application in high-density urban areas.
In view of the above-mentioned problems, on the basis of a comprehensive understanding of the research status at home and abroad, the operation effect of shallow vegetation ditches under rainstorm conditions was evaluated and analyzed. At the same time, the operation data of shallow vegetation ditches accumulated in the International Stormwater Best Management Practices Database for many years were used for statistical analysis and practice. The change of pollutants in shallow vegetation ditches was analyzed from two aspects of ground monitoring. The transport vegetation ditches were improved by adding seepage drainage pipes and reducing planting soil thickness. The effects of weir plates and Plant-type energy dissipation dams on their removal efficiency were analyzed. The accumulation of pollutants in planting soil in shallow vegetation ditches of Niushan Park in Shenzhen was investigated. The operating life is estimated.
The main research contents and results are as follows:
(1) Compared with small rainfall events, the removal efficiency and stability of pollutants in shallow ditches with transported vegetation were reduced, and the average removal efficiency of SS was only 10%. Nitrate dissolved obviously, and the reduction effect of peak runoff and total runoff was also decreased significantly.
(2) Statistical analysis showed that the removal effect of shallow vegetation ditch was not correlated with the influent concentration. The removal effect of shallow vegetation ditch on NO3-, TOC, bacteria, As and Ni was not correlated with the influent concentration. The removal effect of TKN was also correlated with rainfall duration and rainfall. When the rainfall is more than 45 mm, it is difficult for shallow vegetation gully to show good effect of runoff reduction.
(3) The relationship between the removal efficiency of TP, NH4+, COD and SS by shallow vegetation ditch and the length of shallow vegetation ditch conforms to the exponential attenuation model, but the coefficient varies with different influent concentration, and the removal efficiency of NO3 - by shallow vegetation ditch does not conform to the law.
(4) The removal efficiency of pollutants in shallow vegetation ditches was significantly improved after adding seepage drainage pipes, and the retention capacity of shallow vegetation ditches was significantly improved after adding weir plates, but the resuspension of small-sized particles (40 microns) could not be effectively prevented. Compared with weir plates, plant-type energy dissipation dams could significantly control the resuspension of fine particles.
(5) Compared with the surrounding soil, the characteristics of planting soil in the shallow vegetation ditch in Niushan Park have changed significantly. The organic matter content in the planting soil is generally decreasing, and the pH value is lower at the beginning, and the heavy metal content is slightly increased, but it is still in a good range. By estimating, the shallow vegetation ditch in Niushan Park can still be effective. Zn accumulation is the most important factor restricting the life span of shallow furrow vegetation.
【学位授予单位】：北京建筑大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV213.9;TU992
【参考文献】
中国期刊全文数据库 前10条
1 王书敏;于慧;张彬;;生物沟技术在城市面源污染控制中的应用研究进展[J];安徽农业科学;2011年03期
2 孙大志;李绪谦;潘晓峰;;氨氮在土壤中的吸附/解吸动力学行为的研究[J];环境科学与技术;2007年08期
3 徐宗学;张玲;阮本清;;北京地区降水量时空分布规律分析[J];干旱区地理;2006年02期
4 李俊奇;王文亮;边静;陈晓君;徐芳;;城市道路雨水生态处置技术及其案例分析[J];中国给水排水;2010年16期
5 车伍;张伟;李俊奇;;城市初期雨水和初期冲刷问题剖析[J];中国给水排水;2011年14期
6 王肖军;;初期雨水调蓄池在城市排水系统中的应用[J];中国给水排水;2012年10期
7 李静静;李云飞;张宁;张进;徐挺;谢继锋;;合肥市经开区路面径流中重金属污染特征分析[J];安徽农业科学;2012年30期
8 田小松;张洪;张进忠;;重庆市典型降雨径流中颗粒物粒径与重金属污染输出特征研究[J];环境科学与技术;2012年11期
9 陈莹;赵剑强;张小玲;胡博;毛鹤群;;西安市道路雨水口截污挂篮试验研究[J];安全与环境学报;2012年05期
10 阮心玲;张甘霖;赵玉国;袁大刚;吴运金;;基于高密度采样的土壤重金属分布特征及迁移速率[J];环境科学;2006年05期
本文编号：2230811
本文链接：https://www.wllwen.com/kejilunwen/shuiwenshuili/2230811.html
