Description of the sampling sites.

Mangrove forests are fundamental coastal ecosystems for the variety of services they provide, including green-house gas regulation, coastal protection and home to a great biodiversity. Mexico is the fourth country with the largest extension of mangroves of which 60% occurs in the Yucatan Peninsula. Understanding the microbial component of mangrove forests is necessary for their critical roles in biogeochemical cycles, ecosystem health, function and restoration initiatives. Here we study the relation between the microbial community from sediments and the restoration process of mangrove forests, comparing conserved, degraded and restored mangroves along the northern coast of the Yucatan peninsula. Results showed that although each sampling site had a differentiated microbial composition, the taxa belonged predominantly to Proteobacteria (13.2–23.6%), Desulfobacterota (7.6–8.3%) and Chloroflexi (9–15.7%) phyla, and these were similar between rainy and dry seasons. Conserved mangroves showed significantly higher diversity than degraded ones, and restored mangroves recovered their microbial diversity from the degraded state (Dunn test p-value Benjamini-Hochberg adjusted = 0.0034 and 0.0071 respectively). The structure of sediment microbial β-diversity responded significantly to the mangrove conservation status and physicochemical parameters (organic carbon content, redox potential, and salinity). Taxa within Chloroflexota, Desulfobacterota and Thermoplasmatota showed significantly higher abundance in degraded mangrove samples compared to conserved ones. This study can help set a baseline that includes the microbial component in health assessment and restoration strategies of mangrove forests.

红树林是至关重要的海岸生态系统，可提供多种生态服务功能，涵盖温室气体调节、海岸防护，同时孕育了极高的生物多样性。墨西哥是全球红树林面积排名第四的国家，其境内60%的红树林分布于尤卡坦半岛。明晰红树林的微生物组分，对于理解其在生物地球化学循环、生态系统健康、功能维持以及修复实践中的关键作用至关重要。本研究探讨了沉积物微生物群落与红树林修复过程之间的关联，对比了尤卡坦半岛北部海岸的原生保护、退化与修复型红树林的微生物群落特征。研究结果显示，尽管各采样点的微生物组成存在显著分化，但优势菌门主要为变形菌门（Proteobacteria，13.2%~23.6%）、脱硫杆菌门（Desulfobacterota，7.6%~8.3%）与绿弯菌门（Chloroflexi，9%~15.7%），且上述类群的丰度在雨季与旱季之间无显著差异。原生保护红树林的微生物多样性显著高于退化红树林，而修复型红树林的微生物多样性已从退化状态得到恢复（经Benjamini-Hochberg校正的Dunn检验P值分别为0.0034与0.0071）。沉积物微生物群落的β多样性（β-diversity）结构显著响应于红树林保护状态与理化参数，包括有机碳含量、氧化还原电位与盐度。相较于原生保护样地，退化红树林样地中的绿弯菌门（Chloroflexota）、脱硫杆菌门与嗜热原体门（Thermoplasmatota）类群的丰度显著更高。本研究可为红树林健康评估与修复策略中纳入微生物组分提供基准参考。