小流域地下水与地表水微生物组成结构差异及其成因分析

对中山大学滨海水循环综合试验基地的河道水和地下水进行采样,运用16S rRNA基因分析方法,研究微生物的群落组成、结构,同时,通过Mothur软件分析不同采样点的系统发育多样性和文库稀释曲线.结果表明,上下游河道水和地下水均以变形菌(Proteobacteria),厚壁菌(Firmicutes),古菌(Archaea)为优势种群,变形菌在上游堰、下游堰、R1、R2、R3分别占各自总数的29.7%、30.3%、28.1%、20.9%、14.2%;厚壁菌在上游堰、下游堰、R1、R2、R3分别占各自总数的9.7%、20.3%、19.8%、8.6%、39.6%;古菌(不可培养的泉古菌和广古菌)在上游堰、下游堰、R1、R2、R3分别占各自总数的14.2%、12.3%、11.7%、12.1%、3.5%.表明地下水、地表水微生物组成结构有一定的趋同性.另一方面,酸杆菌(Acidobacteria)、硝化螺旋菌(Nitrospira)、拟杆菌(Bacteroidetes) 和Candidate division OPx等在不同采样点的丰度各异,不同埋藏条件下的地下水和地表水多样性指数与稀释曲线有所不同,揭示小流域的微生物组成、结构具有空间差异.研究显示,受周围水文地质条件、补给差异等影响,微生物种群随之演化,微生物特征与水文地质、化学离子密切相关.

Cause on the differences of microorganism between small watershed surface water and underground water

The surface and underground water of Sun Yat-sen University water cycle experiment base was sampled and analyzed by 16S rRNA gene analytical methods to acquire the data of microorganism communities’ distribution,then,the rarefaction curves and richness/diversity estimators were calculated and compared by Mothur software.Microbiological communities in groundwater were similar to those in surface water,with the predominant group of Proteobacterium,Firmicutes,Uncultured Archaeon(uncultured Crenarchaeote and Euryarchaeote).Proteobacteria made up 29.7%、30.3%、28.1%、20.9%、14.2% of the microbial communities from Shangyouyan,Xiayouyan,R1,R2,R3,respectively.The same samples from Shangyouyan,Xiayouyan,R1,R2,R3 also consisted of 9.7%、20.3%、19.8%、8.6%、39.6% Firmicutes and 14.2%、12.3%、11.7%、12.1%、3.5% Archaea,respectively.On the other hand,the data of richness and diversity estimators such as Chao1,Ace,Shannon,and Simpson indicated that microorganism diversities were different in groundwater and surface water,which showed the difference among those microorganism’s characteristics.The study concluded that microorganism evolves in response to the change of the hydrogeological and ionic conditions that are influenced by the water environment and the recharging of water resources.