新型生物岛栅中污染物去除的微生物机制研究

生物岛栅是一种新型的原位水质净化技术.本研究在分析植物生长初期生物岛栅系统(ZLT)对污染物去除效果的基础上,分别利用二喹啉甲酸(BCA)蛋白法和荧光素二乙酸(FDA)酶脂活性法测定微生物量及活性,结合PCR-变性梯度凝胶电泳(DGGE)技术研究了系统中微生物的结构特征.结果表明,ZLT系统对污染物的去除率均明显高于传统浮岛系统(ZL)和仅有填料的对比系统(ZT).ZLT系统中各层填料样品的荧光素和蛋白浓度相差不大,其最高浓度分别为277.5μg.g-1和50.8mg.g-1,但根部样品的浓度仅为95.8μg.g-1和18.1 mg.g-1,相差近3倍.另外2个系统的变化趋势与此类似.DGGE图谱多样性指数分析表明,ZLT中随着水深增加微生物的多样性指数从1.66下降到1.23,但这种趋势在ZL样品中并不明显.在植物生长初期,生态浮岛生物膜上的微生物有超过80%属于γ-变形菌或拟杆菌门.

Microbial Mechanism of Pollutants Removal in New Biological Island Grid

Biological island grid is a new in-situ water purification technology.Based on the analyses of water purification performance of biological island grid system(ZLT) in the initial stage of plant growth,the biomass and activity of microbe in the system are measured with bicinchoninic acid(BCA) protein method and the fluorescein diacetate(FDA) activity,respectively.The microbial characteristics are also detected by PCR-denaturing gradient gel electrophoresis(DGGE) technique.Results showed that the removal of various pollutants in ZLT system was significantly higher than that in traditional floating-bed system(ZL) and control system(ZT),which was only filled with filler.There was little difference in the concentrations of the fluorescein and protein among different layers of filler samples in ZLT.The highest concentrations were 277.5 μg·g-1 and 50.8 mg·g-1 respectively,while they were nearly three times lower in root samples,only 95.8 μg·g-1and 18.1 mg·g-1.The trends of the other two systems were similar.Diversity index analysis of DGGE pattern showed that ZLT samples decreased from 1.66 to 1.23 with the increasing of water depth,but this trend was not evident in ZL samples.More than 80% of the microbe on the biofilm carrier and root belonged to Gamma-Proteobacteria and Bacteroidetes in this stage.