厦门大嶝岛潮间带底栖微藻叶绿素荧光对温度和光照变化的响应

Abstract

采用PAM叶绿素荧光技术,于2013年5月在厦门大嶝岛潮间带,对不同底质类型(泥质、泥砂质和砂质)底栖微藻的光合作用特征进行了初步研究.结果显示:底栖微藻的光合系统II最大光量子效率(fV/fM)呈泥质(0.33)>泥砂质(0.28)>砂质(0.01);底栖微藻叶绿素A含量亦呈上述变化趋势.不同温度(15~35℃)和不同光照透射率(0~100%)的短期(0.5~2.0 H)培养实验表明,底栖微藻光合作用的最适温度(27℃左右)接近于环境温度,体现了其对生长环境的适应;过高的温度(35℃及以上)会抑制光合作用活性,进而限制其生长;此外,光照实验表明底栖微藻可通过自身的运动和变化来适应光照强度的变化,不同底质类型可能存在不同的光适应策略.

Photosynthesis characteristics of the microphytobenthos in different sediment types( mud,mud-sandy and sand) were investigated in intertidal zone of Dadeng Island( Xiamen,China) in May,2013.The results showed that the maximum quantum efficiency( Fv/Fm) of the photosynthetic system II in mud( 0.33) was higher than in mud-sandy( 0.28),and it was lowest in sand( 0.01).The trend was similar with Chlorophyll a content of the microphytobenthos.Short-term( 0.5 ~ 2.0 h) experiments showed the optimum temperature( about 27℃) for microphytobenthic photosynthesis tended to be close to the environmental temperature,and extreme high temperature( above 35℃) was harmful to microphytobenthos.In addition,short-term( 0.5 ~2.0 h) light( 0 ~100%) experiments showed microphytobenthos might accommodate to the light change with different adaptation strategies emerged from different types of sediments,such as migration or change its physiological features.