生态浮床植物选择分析

我国植物资源众多,但由于各种植物的生活习性、处理水质效果以及生长形态不同,导致在选择生态浮床植物时缺乏一个较为完善的系统。在总结前人研究的基础上,将生态浮床植物按一定的方式进行了分类,并对各种植物对氮、磷、重金属物质的水处理效果进行了总结,提出了各种植物之间选择、配比原则以及方案。

不同类型浮床对水质的净化效果研究

生态浮床作为一种环境友好型的水污染治理方法,相对物理化学方法具有较大的优势,自提出以来越来越被广泛关注.目前,生态浮床技术在理论和应用方面都有较深入的研究,但主要集中在植物选择、污染物的去除效果和机理,以及各种创新型浮床,并未将生态浮床作为一个完整的微生态系统进行研究.本文根据植物和微生物的空间分布,模拟设置植物—微生物复合生态浮床系统,研究植物-微生物复合生态浮床、植物浮床和微生物对水质的净化效果,复合生态浮床内部植物和微生物间的相互作用、相互影响.结果表明,不同类型浮床对TP具有较好的去除效果.植物浮床和复合浮床对TP的去除效果均高达90%.复合浮床、植物浮床、微生物处理对水体TN的去除率分别为55.3%、31.2%、31.1%.植物、"植物+微生物"、"植物+空白载体"处理组对植物株高和地径的影响依次变大,主要原因是微生物在富集和形成初期,与植物之间存在养分竞争,影响植物的生长.

浮床植物收割策略及资源化制取生物炭吸附重金属

为了准确制定生态浮床植物收割策略并寻求收割后植物的资源化途径,首先监测浮床中不同植物的茎叶和根系中氮、磷含量的历时变化,然后将收割植物组织在高温限氧环境下裂解制备生物炭,用于废水中重金属的去除并解析其机理。结果表明,浮床植物中菖蒲和千屈菜的茎叶应在每年10月下旬—11月上旬进行收割,而鸢尾和铜钱草无需收割。另外,优选出菖蒲茎叶在400℃下裂解制取的生物炭用于去除废水中的重金属,其对Pb^(2+)、Cu^(2+)、Ni^(2+)和Mn^(2+)的饱和吸附量分别可以达到256.189、52.538、49.141和43.463 mg/g,而且吸附过程符合单分子层吸附的Langmuir模型;除了吸附作用外,生物炭和重金属之间的阳离子π作用以及碱性条件下重金属的沉淀作用也有助于废水中重金属的去除。

Characteristics of Phytoplankton and Its Correlation with Water Environment in SFTWs

[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton＇s community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index＇s range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration.