Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization of Ministry of Agriculture of China, Guangdong Provincial Key Laboratory of Fishery Ecology and Environment, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, PR China.
Guangzhou Haiwei Aquatic Science and Technology Co., Ltd, Guangzhou, PR China.
Microbiologyopen. 2019 Aug;8(8):e00802. doi: 10.1002/mbo3.802. Epub 2019 Feb 7.
To understand the impacts of peanut worms Sipunculus nudus on the prokaryotic community composition in a tidal flat, an onsite investigation was conducted in Suixi in the Beibu Gulf (109.82E, 21.35N) in the burrow sediments, non-burrow sediments and the sediments without peanut worm disturbance (control). The16S rRNA gene Illumina MiSeq sequencing was used to investigate the microbial communities and their response to bioturbation by S. nudus in a sandy tidal flat. A total of 18 bacteria phyla were detected, and Proteobacteria and Cyanobacteria constituted the majority of the prokaryotic community in the samples. The distribution of the relative abundances of genera showed that approximately 6.99%-17% of the reads in the samples were classified into 25 known genera. Sulfate-reducing bacteria (Desulfococcus and Desulfosarcina) were the most abundant taxa, followed by Thermodesulfovibrionaceae LCP-6, indicating that sulfate reduction is the main process in the sandy tidal flat. The abundances of Desulfococcus, LCP-6 and Cyanobacterium in the non-burrow sediment were greater than in the burrow sediment, suggesting that the anoxic condition is more suitable for Desulfococcus and LCP-6 when the activity of S. nudus is absent. The biomass of Cyanobacterium was decreased by the feeding bioturbation of S. nudus. Meanwhile, the relative abundance of the Bacteroidetes Luteimonas in the burrow sediments was significantly greater than in the non-burrow sediment, and there was a strong relationship between S. nudus bioturbation and increased in oxygen contents and oxidation-reduction potentials in the burrow sediment. The abundances of Desulfococcus and LCP-6 were greater in the middle layer (20-30 cm) than in the top layer in the non-burrow sediment. However, the middle and bottom layers (20-30, 30-40 cm) had higher abundances of these genera than did the upper layers (0-10, 10-20 cm) in the burrow sediments. The abundances of the Fusobacteria Propionigenium and the Spirochaetes Spirochaeta were greater in the middle and bottom layers (20-30 cm, 30-40 cm) than in the top layers (0-10, 10-20 cm) in the burrow sediment, but this phenomenon was not found in the non-burrow sediment. This study demonstrates that bioturbation by S. nudus plays an important role in reshaping the bacterial community composition in intertidal regions.
为了了解沙蚕（Sipunculus nudus）对潮滩中细菌群落组成的影响，在北部湾（109.82E，21.35N）的遂溪进行了现场调查，研究了沙蚕洞穴沉积物、非洞穴沉积物和无沙蚕干扰的沉积物（对照）中的细菌群落组成及其对生物扰动的响应。采用 16S rRNA 基因 Illumina MiSeq 测序方法，研究了沙质潮滩中微生物群落及其对沙蚕生物扰动的响应。共检测到 18 个细菌门，其中变形菌门和蓝藻门构成了样品中大多数原核生物群落。属的相对丰度分布表明，样品中约 6.99%-17%的reads 可归类为 25 个已知属。硫酸盐还原菌（Desulfococcus 和 Desulfosarcina）是最丰富的类群，其次是 Thermodesulfovibrionaceae LCP-6，表明硫酸盐还原是沙质潮滩的主要过程。非洞穴沉积物中 Desulfococcus、LCP-6 和蓝藻的丰度大于洞穴沉积物，表明当沙蚕活动不存在时，缺氧条件更有利于 Desulfococcus 和 LCP-6。沙蚕的摄食生物扰动减少了蓝藻的生物量。同时，洞穴沉积物中黄杆菌属（Luteimonas）的相对丰度明显大于非洞穴沉积物，沙蚕的生物扰动与洞穴沉积物中氧气含量和氧化还原电位的增加呈正相关关系。非洞穴沉积物中，中层（20-30cm）的 Desulfococcus 和 LCP-6 丰度大于上层（0-10cm、10-20cm）。然而，洞穴沉积物中中层和底层（20-30cm、30-40cm）的这些属的丰度高于上层（0-10cm、10-20cm）。中层和底层（20-30cm、30-40cm）的梭杆菌属（Propionigenium）和螺旋体属（Spirochaeta）丰度大于上层（0-10cm、10-20cm），但在非洞穴沉积物中未发现这种现象。本研究表明，沙蚕的生物扰动在重塑潮间带细菌群落组成方面起着重要作用。
