Data from: Successive stressors alter microbiome composition and reduce resilience in the eelgrass Zostera marina

Here, we conducted a mesocosm experiment exposing Zostera marina (eelgrass) to fertilized sediments (~70 mg of total nitrogen per 100 g DW sediment-1) for 28 days, followed by a simulated marine heatwave (MHW, 23.3ºC for 15 days) and subsequent storm (25 cm/s flow velocities for 12 days). We demonstrate that eelgrass resistance to nutrient enrichment was driven by specific microbiome shift, particularly enrichment of sulfur-oxidizing bacteria such as Arcobacteraceae (49.2-fold higher) and Sulfurimonadaceae (4.7-fold higher), which likely mitigated sulfide toxicity. In contrast, warming responses were dominated by plant-physiological adjustments. Our results demonstrate that eelgrass resilience depends critically on stressors sequence, where legacy effects alter plant-microbe interactions and physiological responses. While microbial-mediated resistance buffers nutrient stress, thermal acclimation relies on physiological plasticity, highlighting the dual role of ecological memory and temporal stress gradients in seagrass survival. These findings emphasize the need to incorporate both stressor succession and microbiome dynamics into seagrass conservation strategies under climate change.本研究开展了一项中型生态系统实验（mesocosm experiment）：将鳗草（Zostera marina）暴露于富营养化沉积物（每100克干重沉积物约含70毫克总氮）中28天，随后施加模拟海洋热浪（marine heatwave, MHW，23.3℃持续15天）与后续风暴（流速25 cm/s，持续12天）。研究表明，鳗草对营养富集的抗性由特异性微生物组结构改变所驱动，尤以硫氧化细菌的富集为关键：弓形杆菌科（Arcobacteraceae）丰度提升49.2倍，硫单胞菌科（Sulfurimonadaceae）丰度提升4.7倍，这类细菌或可缓解硫化物毒性。与之相对，升温响应主要由植物生理调节所主导。本研究结果显示，鳗草的恢复力关键取决于胁迫因子的作用顺序，遗留效应会改变植物-微生物互作与生理响应。尽管微生物介导的抗性可缓冲营养胁迫，但热驯化依赖于生理可塑性，这凸显了生态记忆与时间胁迫梯度在海草存活中的双重作用。本研究强调，在气候变化背景下，海草保护策略需同时纳入胁迫因子序列与微生物组动态变化。