基于生态安全分析的城市黑臭水体原位治理技术应用研究

原位治理技术在黑臭水体治理工程中应用广泛,但存在治理效果维持时间短,甚至引发二次黑臭的问题。为深入打好黑臭水体治理攻坚战,维护来之不易的治理成效,本研究深入分析几种常见的原位治理技术,归纳总结原位治理技术在应用中存在的局限性或应用误区,点明实施原位修复技术的前提和基础是彻底的控源截污和内源治理,明确各原位治理技术的适用条件,并有针对性地给出对策建议。研究成果可为县级、农村黑臭水体治理工作提供借鉴,推动黑臭水体治理工作向生态、安全、高质量方向发展。     

Scenario simulation of water security in China

Umited water resources, increasing demand, low use efficiency, and serious pollution result in severe water resource difficult in China. The evaluation of addressing water problems and the search for effective countermeasures that ensure sustainable water use are key to China‘ s sustainable development. The “compound water security“ consists of food security, life security, environmental security, and economic security. By establishing a conceptual model, the water security of China has been simulated in terms of four scenarios called BAU(the business-as-usual scenario), TEC(the technology and economics scenario), IVL(the institution, values, and lifestyles scenario) and TSD(toward sustainable development) in this paper. The results indicated that water crises, especially water shortages, are being experienced now and will continue to do so for a relatively long time in China and that it is possible to reach a basic balance between supply and demand of water and grain under the TSD developing pattern by a series of approaches including technological innovation, policy adjustments, and behaviour inducement.     

Succession of aquatic microbial communities as a result of the water quality variations in continuous water

The changes of structural and functional parameters of aquatic microbial communities in continuous water on campus of Tsinghua University, China are investigated by polyurethane foam unit(PFU) method. The measured compositions of the communities include alga, protozoa, and some metazoa (such as rotifers). The measured indicators of water quality include water temperature, pH value, dissolved oxygen (DO), potassium permanganate index(CODMn), total nitrogen(TN), total phosphorus(TP) and chlorophyll- a(Chla). The trophic level, expressed by the trophic level indices(TL/c), is assessed with analytic hierarchy process and principal component analysis (AHP-PCA) method. The changing trends of the structural and functional parameters of aquatic microbial communities, such as Margalef index of diversity(D), Shannon-weaver index of diversity (H), Heterotropy index (HI), number of species when the colonization gets equilibrium(Seq), colonizing speed constant(G) and time spent when 90 percent of Seq colonized in PFU ( T90% ), are also analyzed. The experimental results showed the succession of aquatic microbial communities along the water flow is consistent with the water quality changes, so the parameters of microbial community can reflect the changes of water quality from the ecological view.     

浅水湖泊底泥细菌群落的时空分布特征及主要营养盐驱动因素

为探究富营养化浅水湖泊底泥中细菌群落的结构特征及驱动因素,本研究以安徽八里河湖为例,通过16S rRNA高通量测序手段并结合底泥的营养盐理化性质,分析了底泥细菌群落物种组成和多样性的时空分布特征以及与营养盐的相关性关系。结果显示：(1)在物种组成方面,γ-变形菌纲(Gammaproteobacteria),δ-变形菌纲(Deltaproteobacteria)和拟杆菌纲(Bacteroidia)是八里河湖底泥中的优势菌纲,它们在空间上呈均质性和在季节上有稳定性;(2)在群落结构方面,底泥细菌群落整体上以季节进行聚类,呈现了季节内的相似性和季节间的差异性,且可能来自于鱼类粪便的Clostridia菌纲在八里河湖底泥细菌群落结构差异的塑造上有重要贡献;(3)从四个季节所有样品的整体角度来看,与磷相关的指标(总磷、铁铝结合态磷、钙磷、有机磷)对细菌群落变化的解释最强(r=0.23～0.45,p<0.001),且底泥细菌群落之间的差异性随各磷指标内部之间差异的增大而增大。本研究的发现为认识和理解富营养化浅水湖泊中底泥细菌群落特征及其驱动因素提供了新的信息,对湖泊生态系统健康状态的监测和评...     

水体组分对聚苯乙烯纳米颗粒聚沉行为的影响

微/纳米塑料在环境水体中的团聚和沉降行为是影响其迁移和分布的重要因素.以聚苯乙烯纳米颗粒（PS-NPs）为对象,研究了Na⁺和天然有机质（NOM）两种典型水体组分对其团聚粒径和沉降性能的影响规律,分析了海水、湖水和生活污水等6种水体中团聚、沉降效果及潜在影响因子.结果表明,c（Na⁺） < 80 mmol·L^-1时有利于PS-NPs沉降;反之,则促进其团聚和悬浮.NOM可借助Na⁺在颗粒表面形成多层吸附结构,改变颗粒表面电势和相对密度,进而影响PS-NPs团聚和沉降性能.ρ（NOM） > 10 mg·L^-1时可增强PS-NPs分散和悬浮性能,可能归因于大量附着在颗粒表面的NOM降低了PS-NPs相对密度.环境水体较实验室合成水体更能促进颗粒团聚,这可能与环境水体富含氨基酸和蛋白质等大分子有关.     

改性膨润土对水中磷和藻类的同步去除

为快速去除富营养化水体中的磷和藻类,制备了絮凝剂-镧复合改性膨润土(聚合氯化铝铁-镧复合改性膨润土(PAFC-La)、聚合硫酸铝-镧复合改性膨润土(PAS-La)、聚合硫酸铁-镧复合改性膨润土(PFS-La)、聚合氯化铝-镧复合改性膨润土(PAC-La)),对材料进行表征,通过吸附动力学和等温吸附模型比较4种复合改性膨润土的除磷性能,并探究投药量和pH对复合改性膨润土除磷除藻的影响。结果表明,4种材料吸附磷的过程均能由准二级动力学模型和Langmuir等温吸附模型描述。其中,PAC-La的磷吸附容量最大(44.677 mg/g);投药量为300 mg/L时,总磷(TP)去除率最高的是PAC-La(94.1%),叶绿素a(Chla)去除率最高的是PFS-La(78.2%);在pH为5～10时,PAC-La除磷除藻效果受pH影响最小。实验结果表明,采用絮凝剂-镧复合改性膨润土能够同步去除富营养化水体中的磷和藻类,尤其是采用PAC-La性能最优。     

汾河水体抗生素抗性基因赋存特征

抗生素抗性基因(Antibiotic resistance genes,ARGs)被认为是一种新型污染物,而水环境系统是ARGs释放和传播的重要媒介.为探究汾河水体环境中ARGs的赋存特征及分布特征,选取汾河水体从源头到入黄口的12个位点,对环境因子、ARGs的丰度及多样性,以及二者之间的关系进行研究.结果表明,汾河水...     

稳定塘系统对黑臭水体处理效果的研究

本文以实际工程应用案例为例,研究分析了稳定塘系统对于黑臭水体的处理效果。对项目运营期间监测采样数据的分析结果表明,稳定塘系统对于进水浓度低于20mg/L的COD的去除效果不明显;对NH₃-N、TP和TN均具有一定去除效果,出水水质均能够满足设计出水水质的要求,NH₃-N、TP和TN平均去除率分别为77.28%、76.02%和27.49%。稳定塘系统具有良好的生态环境效益和经济效益,具备较好的推广和应用前景。     

城区富营养化景观水体的生物修复技术

生物修复技术在富营养化景观水体中有其独特的应用价值,本文综述了生物操纵控藻技术、植物控藻技术和微生物控藻技术的研究现状,讨论和展望了不同生物修复技术相互结合在水体修复中的作用.