孝妇河表层沉积物中重金属赋存形态与微生物群落组成

分别采用BCR法和磷酸脂肪酸(PLFAs)分析法测定了孝妇河表层沉积物中Cu、Cr、Pb、Ni的形态分布特征和微生物群落组成,并采用多种统计分析方法研究了2者之间的关系.结果表明,在孝妇河表层沉积物中,Cu、Cr、Pb、Ni均以结晶态为主,其次为可氧化态,酸溶态和可还原态所占的比例较低;孝妇河表层沉积物中微生物群落结构的空间差异性较大;重金属Cu、Cr、Pb、Ni的含量及其不同的化学形态对微生物群落组成的影响不同,其中重金属的总量对微生物量、真菌、总细菌及G+菌均具有抑制作用;而重金属的各化学形态对微生物各类群的影响则各不相同.

Relationship between heavy metals speciation and microbial community structure in surface sediments of Xiaofu River

BCR method was used to study speciation of heavy metal in surface sediment of Xiaofu River. The results indicated that Cu、Cr、Pb、Ni existed mainly in sediment for crystallization and oxidation, little for weak acid extraction and reduction. The microbial community structure and its distribution characteristics in surface sediment of Xiaofu River were studied through phospholipid fatty acids analysis, which indicated that the microbial community structure was different among various sampling sites. The correlation between the heavy metals speciation and microbial structure were analyzed by various statistic methods at the same time. The results indicated the various speciations of heavy metals had different impacts on microbial community structure, in comparison with the total element content. That is, there was a negative relationship between the total content of heavy metals and biomass, fungal group, total bacterial group or the gram-positive group; but for the various speciations of heavy metals, the role metals played in influencing microbial communities was apparently complex and paradoxical.