【摘要】 为了考察发状念珠藻（发菜）在类火星表面半开放体系复苏的可行性,搭建了在线监测模拟类火星环境密闭体系内发菜复苏时放氧速率的试验装置,并考察了水对发菜光合放氧复苏的影响。结果显示,在气压超过5℃、15℃、25℃所对应的水饱和蒸气压时,发菜放氧最高速率分别为5、7和10μmol O₂·h^-1·g^-1（DW）,分别是发菜最大放氧速率的1%、2%和3%;而在气压低于相应的水饱和蒸气压时,发菜放氧平均速率分别下降为1、2和3μmol O₂·h^-1·g^-1（DW）,且随着反应时间的延长,发菜在5℃放氧速率下降为0;然而,在5℃,气压为1.7¹.9 k Pa,加入10 mL BG11时,发菜放氧速率最高上调至12μmol O₂·h^-1·g^-1（DW）。以上结果显示,水对发菜在类火星表面半开放体系复苏的影响大于气压。更多还原

【Abstract】 To investigate the recovery feasibility of Nostoc flagelliforme in a semi-open system under a Mars-like surface environment,an on-line O₂ evolution rate monitoring system for N. flagelliforme recovery under a mimetic closed Mars-like surface environment was established,and the effects of water on the photosynthetic O₂ evolution of N. flagelliforme was were investigated in this system.The results showed that at the temperatures of 5℃,15℃,and 25℃,when the atmospheric pressure exceeded the vapour pressures of the corresponding temperatures,the maximum O₂ evolution rate of N. flagelliforme reached 5,7,and 10 μmol O₂·h^-1·g^-1（ DW）,respectively,which represented only 1%,2%,and 3% of the O₂ evolution rate of N. flagelliforme under optimum conditions.When the atmospheric pressures were lower than the vapour pressures of the corresponding temperatures,the average O₂ evolution rate of N. flagelliforme declined to 1,2,and 3 μmol O₂·h^-1·g^-1（ DW）,respectively. With the extension of time,the O₂ evolution rate declined to zero at 5℃.However,under a temperature of 5℃ and atmospheric pressure of 1. 7 1. 9 k Pa,the addition of 10 m L BG11 medium led to an increase of maximum O₂ evolution rate up to 12μmol O₂·h^-1·g^-1（ DW）. These findings indicated that the effect of water on the recovery of the semi-open system under a Mars-like surface environment was greater than that of atmospheric pressure.更多还原