深海热液区是微生物多样性最丰富的环境，但其原因并不明了。前期申请人提出“多因子环境适应存在共同机制”假说，并推测一定范围内的环境波动是种类分化与微生物多样性上升的重要原因。大洋35航次中，我们利用蛟龙号携带的温度探头检测到热液喷口温度半日潮周期性变化，温差可达30℃以上。本研究以西南印度洋龙旂热液区、东太平洋海隆热液区等不同烟囱体样本为生物材料，开展受控环境下的模拟实验，监测微生物菌群的演变，从中找出热液微生物群体从物质交换、能量代谢、协同与拮抗、基因组冗余等方面应对多重胁迫因子的生存策略。同时以新分离的广谱耐受的热液超嗜热古菌Thermococcus eurythermalis A501为模式菌株，研究其对温度、盐度、pH、氧化还原度、环境波动等多重胁迫因子的适应机制及其对生态功能影响。本研究将验证申请者先期提出的假说，为我国西南印度洋（微）生物多样性保护提供科学依据。

Deep sea hydrothermal vent have most species of microbes，but knowledge of the process that cause biodiversity is lacking. We propose that “Common adaptation strategy allows microorganisms adapt to HHP like other stresses” and such amount species that have likely emerged through environmental fluctuation adaptation. In the second leg of Dayang 35 Cruise, results of 8 days continuous temperature observation on ultraslow-spreading Southwest Indian Ridge show there are semidiurnal tide cycles, up to 30℃ range. In this project, firstly we will investigate chimney samples from SWIR and EPR, by characterizing the community evolution under well controlled environments, to illustrate the life strategies coping with multiple stress in energy metabolism, synergistic and antagonistic reactions and genome redundancy at a community level. Then we will use a typical hyperthermophilic archaea Thermococcus eurythermalis A501 as model organism, to investigate the mechanisms to adapt to environments with multiple stresses such as temperature, salinity, pH, redox, nutrients, fluctuation and so on, looking for the key metabolic pathways and their influence to the whole ecosystem. We will verify our hypothesis and provide scientific proof for SWIR biodiversity protection.