不同温度条件下无机碳浓度增高对石莼光合作用的影响

THE EFFECTS OF ELEVATED INORGANIC CARBON CONCENTRATION ON PHOTOSYNTHESIS OF Ulva lactuca UNDER DIFFERENT TEMPERATURE

为了探讨在不同光温条件下石莼 (Ulvalactuca)光合作用对无机碳的需求 ,于1999年6～7月 ,在提高海水无机碳浓度(8.8mol/L)的条件下 ,对石莼光合作用的光温反应特性进行了研究。结果表明 ,无机碳浓度增高对石莼光合作用的影响对温度有依赖性。增加无机碳浓度 ,在30℃较高温度下 ,显著地提高了光饱和光合速率 ,而在10℃较低温度下 ,其影响不明显。在温度20～30℃范围内时 ,无机碳浓度增高使光饱和光合速率的温度系数增加,而在温度10～20℃范围内时则没有影响。较高的光温度条件使石莼光合作用对无机碳的需求增加。

The photosynthetic responses of Ulva lactuca to light and temperature were investigated under elevated inorganic carbon concentrations during the period of June to July, 1999. It was found that effects of elevated inorganic carbon concentration on the photosynthesis were temperature dependent. Elevated inorganic carbon concentration increased the light saturated photosynthesis at 30 ℃, but did not affect it at 10 ℃. Elevated inorganic carbon significantly increased the temperature coefficient of light saturated photosynthetic under higher temperature range (20～30 ℃). However, it did not affect the temperature coefficient of light saturated photosynthetic under lower temperature range (10～20 ℃). The photosynthetic inorganic carbon demand increased with increasing light temperature conditions.