【作者】 凌云；

【导师】 徐亚同；

【作者基本信息】 华东师范大学 ， 环境科学， 2007， 博士

【摘要】 人工湿地是由人工建立的具有湿地性质的污水处理系统。它利用湿地生态系统中的物理、化学和生物的三重协同作用,来实现污水的净化,有高效率、低投资、低能耗、低运行费用、易维护管理等优点,已在污染水体的生态修复中有所应用。作为苏州河环境综合整治成果的集中展示,苏州河梦清园水系依据生态学的原理,采用了生态重建技术,充分发挥水生生态系统各种组分的功能来净化水质和优化景观效果。在整个技术应用中,芦苇湿地是整套水系的重要一环。本文依托上海863项目上海城市水环境质量改善技术与综合示范(编号2003AA601020)子课题——景观水体微生物与酶强化净化技术研究,以上海市梦清园芦苇湿地系统为主要研究对象,研究了强化的微生物处理措施对于苏州河水在芦苇湿地中的净化效果,同时结合梦清园的实地运行情况,研究了强化植物作用和底栖动物作用所可能产生的效果。此外,论文对生物净化的机理也进行了一定的研究,为人工湿地在受损生态系统修复中的应用提供技术依据和理论指导。主要研究结论如下:1)本文考察了现有的多种商品菌剂对苏州河水C、N、P污染物的去除效果并驯化培养适合苏州河水体的高效菌剂。结果表明现有菌剂对提高有机污染物的去除有一定作用。经过3周左右的进一步驯化培养,得到的复合菌剂在12小时内对苏州河水的COD去除率可高于空白1倍,对氨氮去除率最高可达到88.4%。2)在芦苇湿地围隔内进行的强化微生物作用试验表明,经过处理,苏州河水的多项指标均有好转,加菌组和空白组氨氮的年平均去除率分别为30%和20%,总氮年平均去除率为24%和20%,总磷为23%和20%。加入菌剂后对氮磷处理效果明显。3)对于植物的强化作用研究结果表明,芦苇根际的泌氧作用使根际土壤的氧化还原电位(ORP)一直维持在+100mV左右,而非根际的ORRP一直为负值。从4月到7月,根际土壤呼吸强度从0.55CO2mg/g·d增加到0.76 CO2mg/g-d,而非根际土壤则在0.50CO2mg/g·d左右波动,且根际土壤呼吸强度与微生物数量有显著负相关。由于根际泌氧和营养作用,微生物数量的根际效应十分明显,异养细菌、真菌和放线菌的根际/非根际比值(R/S值)分别为11.8、11.9和11.7;反硝化细菌、硝酸细菌和亚硝酸细菌的R/S值分别为14.1、17.3和22.4。芦苇的存在对于微生物的生长有显著作用。4)梦清园芦苇对氮磷的净化效果研究表明,芦苇地上部生物量在10月底11月初达到最高值,2980.8g/m2。芦苇地上部分含氮量在秋季最高,达1.64%,而后含氮量逐渐下降,芦苇地上部分磷含量变化与氮类似,在秋季最高,达0.23%。综合芦苇地上生物量和氮磷含量考虑,10月底11月初进行芦苇收割是一个最佳时期,此时通过收割去除的氮可达到485.7kg/hm2,磷的去除可以达到67.9kg/hm2。5)对于底栖动物(螺蛳和蚌)的强化净化作用效果研究表明,静态试验中螺蛳和蚌可以明显降低苏州河水浊度。试验组最快可在4个小时内将水体浊度下降到稳定状态,螺蛳的净化效果优于蚌。动态试验中,在相同的HRT条件下,试验组的平均浊度去除率在66.0%-83.2%,优于空白对照组。在HRT为2.5h的情况下,螺蛳密度在400～800个/m2时浊度去除率可达35%以上。综合成本考虑,400个/m2是系统最佳的投放量。而在800个/m2的螺蛳投加密度下,最佳停留时间为6h,去除率可达68%。6)对梦清园湿地中微生物群落结构变化进行的研究表明,芦苇湿地不同采样点的根际微生物数量均高于非根际,在夏秋季节,异养细菌数量可高于2个数量级。而酶制剂和生物促生剂的加入使得非根际和根际的微生物数量和酶活都得到提高,明显高于对照组,为污染物的降解创造了有利条件。7)对湿地系统的氮磷季节分布研究表明,藻类固氮在梦清园湿地中的作用很小,进水输入是系统主要的氮来源。而湿地主要的脱氮方式依然是硝化反硝化脱氮,最高可达71.86g/m2,占春季系统脱氮量的76.41%;其次是植物对氮的吸收作用,最高可达34.57g/m2,占夏季湿地脱氮量的39.38%。底泥对氮的吸附作用较弱,更多依靠底泥沉积带入氮素,占脱氮总量的约10%。在磷的去除中,基质的吸附是系统除磷的主要方式。一直保持在50%以上。春季可达92.08%,而秋季最低也占去除率的57.81%。植物的吸收量随季节变化比较明显,在夏、秋、冬三季,植物的磷吸收量可以占到总磷去除比例的20%以上。更多还原

【Abstract】 Constructed wetland as a kind of dirty water treatment system is an artificial building which has wetland properties. Physical, chemical and biological degradation are the ways to purifying the dirty water. Due to benign eco-friendliness, energy-saving and low operating costs, it is attracting attention in the bioremediation of polluted water.As a crystallization of synthesized treatment of Suzhou River, Mengqing Garden based on the ecological rules. Ecological restoration technique and aquatic ecosystems are used to improve the water quality and the landscape. As one of the key parts in the Mengqing Garden, the constructed wetland was studied in this text. This work is subproject of "Improvement technology and case study of Shanghai city water environment" （Project No: 2003AA601020）. The augmentation of bioremediation of the microbe, reed and zoobenthos were studied in the work, as well as mechanisms of the bioremediation studied. The conclusions are the technical basement and theory reference to the applying of the constructed wetland in bioremediation, which were drawn as follows:1) The degradation effect of C, N and P in the Suzhou River by different commercial inocula were studied. The result indicated the inocula are efficiency to the pollutions. High solution microbes to the Suzhou River were achieved after 3 weeks Culturing and the ability to degradation the COD of Suzhou River is one times higher than the controlled group in 12h, the remove ratio of the ammonia could be 88.4%.2) In mesocosm experiment, the degradation rate of ammonia is 30% in test group and 20% in controlled group per year while the TN and TP have 24%, 23% in test group and 20%, 23% in controlled group, which indicated the affective of the inocula.3) With the contribution of root oxygenation, the soil oxidation-reduction potential （ORP） maintained at the +100mV in rhizosphere, while the non-rhizosphere maintained negative. The respiration intensity in the rhizosphere decreased from 0.76 CO₂mg/g·d to 0.55 CO₂mg/g·d from April to July in the rhizosphere while non-rhizosphere maintained at 0.50 CO₂ mg/g·d. By the contribution of root oxygenation, the rhizosphere effects of microorganism are obviously. The ratio of bacteria, fungi and actinomyces in the rhizosphere and non-rhizosphere （R/S） are 11.8, 11.9 and 11.7. The R/S ratio of nitrobacteria, Nitrosomonas and denitrifying bacteria were 14.1, 17.3 and 22.4. The result proved the reed had positive affect to the development of the microorganism.4) Study of biomass and nutrition contents of the reeds showed that the aboveground part of the reeds grown from March to November, the maximum biomass was 2980.8g/m² which showed in the end of October. The nitrogen content of the aboveground reached the maximum in autumn, which was 1.64%, The phosphors content of the aboveground was similar to that of the nitrogen, which have reached the maximum 0.23% in autumn. According to the biomass of aboveground and the nitrogen and phosphors contents, the best time for the harvest was in the end of October. By then, the removing of the nitrogen will reach 485.7kg/hm² and 67.9 kg/hm² of phosphors with the harvest of the plants.5) The batch test of the turbidity degradation on zoobenthos （spiral shell and mussel） shows that spiral shell and mussel could significantly reduce the turbidity of the Suzhou River. The test group could reduce the turbidity to the stable state in only 4 hours. The degradation effect of spiral shell was better than that of the mussel. The result of the dynamical test shows that the average turbidity degradation rate was 66.0%-83.2% of the test group under the same HRT condition, which was better than the controlled group. When the HRT was 2.5h and the density of spiral shell was 400-800/m², the turbidity degradation rate could be above 35%. The density of the spiral shell of 400/ m² could be the best for the system considering the cost of the project. When the density of the spiral shell was 800/ m², the best HRT was 6h and the turbidity degradation rate could be 68%. he results shows that the spiral shell could play a big role in the Mengqin Garden.6) The result of the microbe’s community structure shows, the microbe quantity of the rhizosphere is higher than the non-rhizosphere, and the bacteria quantity could be 100 times more than the non-rhizosphere in summer and autumn. The use of inocula increased the microbe quantity of the mesocosm, obviously higher than the controlled group.7) The research of the seasonal distribution of nitrogen and phosphorus in wetland system indicates that the nitrogen fixation of algae doesn’t play an important role in the wetland of Mengqing Garden. It also indicates that influent is the major nitrogen resource of the system. Nitrification-denitrification is the main path of denitrogenation in the wetland. And it removed 71.86g/m² N, which was 76.41% of total denitrogenation in spring. The reeds remove 34.57g/m² which were 39.38%. The adsorption of sediments is the weakest, which takes about 10%. In the removal of phosphorus, the adsorption of the sediments is the main path of phosphorus removal which remains more than 50% constantly. The highest is 92.08% in spring, and lowest is 57.81% in autumn. The absorption of plants changes apparently as the seasons. It takes more than 20% of the removal of total phosphorus in summer, autumn and winter.更多还原