intertidal mangrove wetlands Raw sequence reads. wetland metagenome

Intertidal mangrove wetlands are of great economic and ecological importance. The regular influence by tide leading to the microbial communities in these wetlands differs significantly from other habitats. The effect of anthropogenic activity that protecting mangrove wetlands from tide on the microbiomes are not understood. In this study, we investigate mangrove species related microbiomes in protected (Bamen Bay) and natural intertidal wetlands (Dongzhai Bay) from two mangrove wetlands in Hainan Island. Soil samples from 13 mangrove species root zone were collected. Microbial composition was assessed using Illumina sequencing. Our bioinformatics analyses indicate that microbiomes shifted significantly between mangrove wetlands with and without anthropogenic protection. In protected site, microbiomes were more similar to those of terrestrial and freshwater ecosystems, whereas in natural site were more related to marine and other intertidal wetlands. The overall microbiome was assigned into 78 phyla and Proteobacteria is the most abundant group in both sites at phylum level. At class level, however, an even distribution of Alph, Beta, Gamma and Delta Proteobacteria was found in Bamen Bay, whereas the Gamma and Delta Proteobacteria were more dominant in Dongzhai Bay. Functional consortia of sulfate reducing bacteria (SRB) was mostly occurred in Dongzhai Bay; nitrite oxidizing bacteria, ammonia oxidizing arhea (AOA) were major groups in nitrification process; the relative abundances of methanogens and methanotrophs were not exceed 1%, indicating a weak methane generation and oxidation in both sites. We also observed distinct microbial compositions among mangrove species in Bamen Bay. Our data suggest that mangrove species and pH are main factors influence microbiomes in protected mangrove wetland.

潮间带红树林湿地兼具极高的经济价值与生态重要性。潮汐的周期性浸淹使得此类湿地中的微生物群落与其他生境存在显著差异。目前学界对于人类通过防护工程使红树林湿地脱离潮汐影响的活动，对其微生物组造成的效应仍不明晰。本研究以海南岛两处红树林湿地为研究对象，分别选取受人工防护的八门湾（Bamen Bay）与自然潮间带湿地东寨港（Dongzhai Bay），对与红树林物种相关的微生物组展开调查。研究采集了13种红树林物种根际区域的土壤样品，采用Illumina测序技术对微生物群落组成进行分析。生物信息学分析结果显示，受人工防护与未受防护的红树林湿地的微生物组存在显著分化：受防护站点的微生物组与陆地及淡水生态系统的群落结构更为相似，而自然站点的微生物组则更接近海洋与其他潮间带湿地。整体微生物组共划分为78个菌门，在门分类水平上，变形菌门（Proteobacteria）为两个站点的优势菌门。而在纲分类水平上，α-变形菌纲、β-变形菌纲、γ-变形菌纲与δ-变形菌纲在八门湾呈现均匀分布，东寨港则以γ-变形菌纲和δ-变形菌纲占主导。硫酸盐还原菌（sulfate reducing bacteria, SRB）的功能类群主要分布于东寨港；亚硝酸盐氧化菌与氨氧化古菌（ammonia oxidizing archaea, AOA）是硝化过程的主要功能类群；产甲烷菌与甲烷氧化菌的相对丰度均未超过1%，表明两处站点的甲烷生成与氧化过程均较为微弱。此外，八门湾内不同红树林物种的微生物群落组成也存在显著差异。本研究数据表明，红树林物种与土壤pH值是影响受防护红树林湿地微生物组的主要驱动因素。