博斯腾湖西岸人工湿地水体净化及土壤改良效果研究

发布时间：2018-05-09 14:23

本文选题：博斯腾湖西岸 + 人工湿地　；参考：《新疆师范大学》2017年硕士论文

【摘要】：人工湿地是为了处理污水,模仿天然湿地而建造的工程化的湿地除污系统。这种湿地通过人工设计,在具有一定长宽比的洼地中由砾石、土壤等材料组成混合的湿地床上种植植物。污水从湿地床体一端流进,经过植物、微生物等的协同作用从另一端流出进而达到除污效果。作为一类新型的污水处理技术,与传统的二级、三级等处理技术相比具有成本低、工艺设备简单、系统各要素配置可塑性强、高生态效应等优点,因此被广泛应用于农村、中小城市污水处理、农业面源污染控制及湖泊综合治理。我国人工湿地多建于南方,且各地区人工湿地建设情况均不相同,本文以博斯腾湖西岸人工湿地为研究对象,探索了干旱区人工湿地在运行过程存在的问题及污染去除效果等问题。博斯腾湖是第三纪末期新构造运动下形成的断陷湖泊,作为蒙新湖区典型的内陆淡水湖泊,近些年来随着当地人口的大规模的增长、工业、农业的发展,人们对淡水资源进行掠夺式的开发利用,使得入湖污染负荷增加并严重破坏了湖滨湿地、面临着生态容量降低、水体矿化度增加、生物量减少,部分区域芦苇已经不能自然生长等问题。为改善湖泊生态环境,在各级政府的大力支持和帮助下及大量文献阅读和参观实体人工湿地、反复实验论证。由博斯腾湖县金海育苇有限责任公司牵头,新疆师范大学主动参与理论研究并共同建设博斯腾湖西岸人工湿地。本文依托课题项目,2015年4~(-1)0月连续7个月在该人工湿地各期工程的进水口、出水口进行水样采样,对比分析人工湿地4~(-1)0月及沿程水体污染物的变化规律。2015年4月、6月、8月在人工湿地内、外采集土壤样品,对比分析人工湿地内、外土壤盐分、养分变化情况。得出以下结论:(1)通过对博斯腾湖西岸人工湿地水样4~(-1)0月份及沿程不同样点的监测结果显示,2015年4~(-1)0月人工湿地的进、出水中TN、NH_3~-N、NO_3~--N、NO_2~--N浓度平均消减量分别为7.94 mg·L~(-1)、4.85 mg·L~(-1)、1.19 mg·L~(-1)、0.61 mg·L~(-1)。进水口,氮浓度在8月份最高,10月份最低;出水口,氮浓度在9月份出现最大值,6月份出现最小值。TN、NH_3~-N、NO_3~--N、NO_2~--N浓度在进、出水处均表现为先上升后下降。去除率分别为55.39%、62.96%、71.72%、74.10%,TN、NH_3~-N的去除率表现为先上升后下降趋势,NO_3~--N和NO_2~--N则表现为去除率呈现为先下降后上升再下降的态势。人工湿地水体中NH_3~-N对TN的去除贡献最高,贡献率为61.16%。博斯腾湖西岸人工湿地对水体污染物去除效果显著,水质改善明显。人工湿地进水口到出水口的沿程变化中TN、NH_3~-N、NO_3~--N、NO_2~--N浓度沿程逐渐降低,在人工湿地前端的消减量较大,平均消减量达到90%以上。(2)对博斯腾湖西岸人工湿地中磷浓度监测结果显示,2015年4-6月,进出水口中TP浓度消减量为1.66 mg·L~(-1),去除率为67.36%。去除率最大值出现在7月,为91.6%,TP的去除率表现为先上升后下降的态势,去除效果较好。人工湿地沿程水体中TP浓度由1#到7#样点逐渐降低。其中,1#-3#样点浓度降幅最大,降幅为3.92 mg·L~(-1),消减贡献率超过90%。(3)有机物以BOD_5和COD为代表,对博斯腾湖西岸人工湿地水体监测显示,2015年4-6月BOD_5和COD进出水浓度平均消减量分别为3.79 mg·L~(-1)、22.34 mg·L~(-1),去除率分别为57.85%和40.12%,有机物去除率效果较差。沿程变化中BOD_5、COD浓度在1#-4#样点变化趋势相似,呈现缓慢下降态势,4#样点之后BOD_5有小幅上升态势。(4)对比人工湿地及对照组土壤养分指标发现人工湿地和其对照组中土壤各养分指标差异明显,人工湿地中土壤养分高于对照组,各样点显示土壤养分指标中有机质含量较为丰富,其他养分含量较贫乏,说明人工湿地的运行提高了土壤养分含量。土壤中盐分含量变化表现为随土层深度增加各盐分离子含量不断减少,呈现明显的表聚型,其中阴离子以SO_4~(2-)为主,阳离子则以Na~++K~+含量最大。(5)运用主成分分析法和相关分析法分析博斯腾湖西岸人工湿地水体和土壤主要污染主导因子,结果显示,水体中主要污染因子为COD、NH_3~-N、NO_2~-N。土壤盐分主导因子为SO_4~(2-)、Na~++K~+、HCO~(3-)。相关分析显示,SO_4~(2-)与Na~++K~+呈现显著正相关关系,BOD_5和植物密度、水体温度呈现显著正相关。
[Abstract]:Constructed wetland is an engineered wetland decontamination system built to treat sewage and mimic natural wetlands. This wetland is artificially designed to plant plants in a mixed wetland bed with gravel, soil and other materials in a low-lying land with a certain length and width. Sewage flows from one end of the wetland bed, through plants, microbes and so on. As a new type of sewage treatment technology, as a new type of sewage treatment technology, compared with the traditional two grade and three grade treatment technology, it has the advantages of low cost, simple process equipment, high plasticity and high ecological effect, so it is widely used in rural areas, small and medium urban sewage treatment, agricultural non-point pollution. The construction of artificial wetland in China is different in the south, and the construction of artificial wetlands in various regions is different. In this paper, the problems in the operation process of artificial wetland in the arid area and the effect of pollution removal are explored in this paper. Bosten Lake is a new structure at the end of the third period. As a typical inland freshwater lake in the Mengxin Lake area, as a typical inland freshwater lake in the Mengxin Lake area, in recent years, with the large-scale growth of the local population, the development of industry and agriculture, the exploitation and utilization of fresh water resources make the pollution load of the lake increase and seriously destroy the Lakeside wetland, and the ecological capacity is reduced and the water body is reduced. In order to improve the ecological environment of the lake, in order to improve the ecological environment of the lake, with the support and help of the governments at all levels, a large number of literature reading and visiting the solid constructed wetland have been proved repeatedly. It is led by the Jinhai reed limited liability company of Bosten Lake County, and the master of Xinjiang Normal University. The research and construction of artificial wetland in the West Bank of Bosten Lake. This paper is based on the project. In 2015 4~ (-1) 0 months, the water sample was sampled at the inlet of the constructed wetland and the outlet of the constructed wetland for 7 months. The changes of the 0 month and the water body pollutants in the artificial wetland 4~ (-1) were compared and analyzed in April, June and August. In the wetland, the soil samples were collected, and the changes of soil salt and nutrients in the artificial wetland were compared and analyzed. The following conclusions were obtained: (1) through the monitoring results of 4~ (-1) in the West Bank of Bosten Lake in 0 months and the different points along the path, the concentration of TN, NH_3~-N, NO_3~--N, NO_2~--N in the effluent of 2015 4~ (-1) 0 months The average attenuation was 7.94 mg. L~ (-1), 4.85 mg. L~ (-1), 1.19 mg. L~ (-1), 0.61 mg. L~ (-1). The nitrogen concentration was the highest in August and the lowest in October; the concentration of nitrogen appeared in September and the minimum value appeared in June. The removal rates of 55.39%, 62.96%, 71.72%, 74.10%, TN, and NH_3~-N were first increased and then descended, while NO_3~--N and NO_2~--N showed that the removal rate was first descended and then decreased. The contribution of NH_3~-N to TN was the highest in the artificial wetland water, and the contribution rate was the water pollution of the artificial wetland on the West Bank of Bosten Lake in 61.16%.. TN, NH_3~-N, NO_3~--N, NO_2~--N concentration decreased gradually along the range of the inlet of the constructed wetland to the outlet, and the decrease in the front-end of the constructed wetland was more than 90%. (2) the monitoring results of phosphorus concentration in the artificial wetland on the West Bank of Bosten Lake showed that 4-6 months of 2015, The elimination rate of TP concentration in the inlet and outlet is 1.66 mg. L~ (-1). The maximum removal rate of 67.36%. removal rate appears in July, which is 91.6%. The removal rate of TP is shown to rise first and then descend, and the removal effect is better. The concentration of TP in the artificial wetland is gradually reduced from 1# to 7# samples. Among them, the 1#-3# sample point concentration is the largest and the decline is 3.92 mg. L~ (-1), the reduction contribution rate is more than 90%. (3) of organic matter represented by BOD_5 and COD. The monitoring of water body in the West Bank of Bosten Lake shows that the average elimination of BOD_5 and COD in 2015 is 3.79 mg. L~ (-1), 22.34 mg and 40.12% respectively. The removal rate of organic matter is 57.85% and 40.12%, and the removal efficiency of organic matter is poor. OD_5, COD concentration was similar in the 1#-4# sample point, and showed a slow downward trend. After 4# sample, BOD_5 had a small upward trend. (4) compared with artificial wetland and control group, the soil nutrient indexes of artificial wetland and its control group were obviously different. The soil nutrients in artificial wet land were higher than those of control group, and the soil nutrients were higher than those in the control group. The content of organic matter in the nutrient index is more abundant and the other nutrient content is poor, which indicates that the operation of the artificial wetland improves the soil nutrient content. The change of the salt content in the soil shows that the content of the salt ions in the soil decreases continuously with the depth of the soil layer, and shows the apparent aggregation type. The main anions in the soil are SO_4~ (2-), and the cation is Na~++K~+ (5) principal component analysis and correlation analysis were used to analyze the main pollution leading factors of water and soil in the West Bank of Bosten Lake. The results showed that the main pollution factors in the water body were COD, NH_3~-N, NO_2~-N., SO_4~ (2-), Na~ ++K~+, HCO~ (3-). The correlation analysis showed that SO_4~ (2-) was presented with Na~++K~+. There was a significant positive correlation between BOD_5 and plant density, and there was a significant positive correlation between water temperature and water temperature.

【学位授予单位】：新疆师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X703

【参考文献】