Wang Chuan, Liu Shuangyuan, Zhang Yi, Liu Biyun, Zeng Lei, He Feng, Zhou Qiaohong, Wu Zhenbin
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, No. 7 Donghu South Road, Wuchang District, Wuhan, 430072, China.
University of Chinese Academy of Sciences, 19 A Yuquan Rd., Shijingshan District, Beijing, 100049, China.
Microb Ecol. 2017 Aug;74(2):278-288. doi: 10.1007/s00248-017-0951-9. Epub 2017 Mar 2.
Submerged macrophytes play an important role in aquatic ecosystems, which has led to an increase in studies on vegetation recovery in polluted lakes from which submerged macrophytes have disappeared. The comparison of microbial communities in sediment cloned with planted and naturally growing submerged macrophytes is an interesting but rarely studied topic. In this investigation, Maojiabu and Xilihu, two adjacent sublakes of West Lake (Hangzhou, China), were selected as aquatic areas with planted and naturally growing macrophytes, respectively. Sediment samples from sites with/without Vallisneria natans were collected from both sublakes. The results showed that sediment total nitrogen and organic matter were significantly lower in the plant-covered sites than that in the non-plant sites in Maojiabu. Additionally, the sediment microbial community characterized by 16S ribosomal RNA (rRNA) sequencing differed more significantly for Maojiabu than for Xilihu. The relative abundances of microbes involved in C, N, and S elemental cycling were significantly higher in the sediments with plants than in those without. Results from both fatty acid methyl ester analysis and 16S rRNA sequencing indicated that vegetation significantly influenced the sulfate-reducing bacteria (SRB). Thus, the gene copies and composition of SRB were explored further. The relative gene abundance of SRB was 66% higher with natural vegetation colonization but was not influenced by artificial colonization. An increase in dominant SRB members from the families Syntrophobacteraceae and Thermodesulfovibrionaceae contributed to the increase of total SRB. Thus, macrophyte planting influences sediment nutrient levels and microbial community more than natural growth does, whereas the latter is more beneficial to sediment SRB.
沉水植物在水生生态系统中发挥着重要作用，这使得对受污染湖泊中沉水植物消失后的植被恢复研究有所增加。比较种植和自然生长的沉水植物所在沉积物中的微生物群落是一个有趣但很少被研究的课题。在本研究中，分别选取了杭州西湖相邻的两个子湖茅家埠和西里湖作为种植和自然生长大型植物的水域。从两个子湖中有/无苦草的位点采集沉积物样本。结果表明，茅家埠有植物覆盖的位点沉积物总氮和有机质显著低于无植物位点。此外，茅家埠以16S核糖体RNA（rRNA）测序表征的沉积物微生物群落差异比西里湖更显著。参与碳、氮和硫元素循环的微生物相对丰度在有植物的沉积物中显著高于无植物的沉积物。脂肪酸甲酯分析和16S rRNA测序结果均表明，植被显著影响硫酸盐还原菌（SRB）。因此，进一步探究了SRB的基因拷贝数和组成。自然植被定殖时SRB的相对基因丰度高出66%，但不受人工定殖的影响。互营杆菌科和嗜热脱硫弧菌科等优势SRB成员的增加导致了SRB总数的增加。因此，种植大型植物比自然生长对沉积物养分水平和微生物群落的影响更大，而自然生长对沉积物SRB更有益。
