Pb^(2+)污染对凤眼莲根系微生物的影响

Effects of Pb^(2+) Pollution on the Micro-organisms of Eihhornia Crassipes Roots

研究系列浓度铅污染对凤眼莲根系的细菌、放线菌、霉菌和酵母菌等的活菌数和相应水样的DO(溶解氧量)、COD(化学需氧量)的影响.结果表明,Pb2+对凤眼莲根系微生物的数量及水样DO值和COD值的影响具有时间和浓度上的双重效应.细菌为凤眼莲根系微生物的优势类群,当Pb2+高于0.25 mmol.L-1时会减少细菌的数量,影响其净化水体的能力.DO值和COD值与凤眼莲根系微生物的数量增长存在密切关系.

The effects of Pb2＋ pollution on the amount of the Bacteria,Actinomycosis,Streptomyces and Yeast of the Eichhornia Crassipes root cultivated in the water with various concentration of Pb2＋ ranging from 0 to 2.0 mmol·L-1 were studied,accompanied with monitoring DO,COD from corresponding sample water.The results shows that the amount of those micro-organisms of Eichhornia crassipes root and the value of DO,COD influenced by Pb2＋ depend on both treating time and concentrations of Pb2＋.Bacteria is dominant kind of these micro-organisms.The number of Bacteria decrease under the pollution stress of Pb2＋ with higher than 0.25 mmol·L-1,which would decrease the capability of Eichhornia crassipes to clean water body.There exists a close relationship between DO,COD and the growth of micro-organisms in water body.