盐度、温度和光照强度对针叶蕨藻的生长及光合活性的影响

Effects of Salinity, Temperature and Light Intensity on Growth and Photo- synthetic Activity of Caulerpa sertularioides

摘要:

为探究环境因子对针叶蕨藻（Caulerpa sertularioides）生长的影响，对不同盐度、温度和光照强度下针叶蕨藻的生长和叶绿素荧光参数进行了研究。结果表明：藻体日特定生长率（SGR）、最大光量子产量（F_v/F_m）、实际光合效率（Yield）、电子传递速率（ETR）和光化学淬灭（qP）随盐度升高呈先上升后下降的变化趋势，非光化学淬灭（qN）则呈相反的变化趋势，藻体光合活性和固碳效率在盐度27.5‰时达到最高，且与25‰和30‰盐度的差异显著（P<0.05，n=3）。藻体SGR、F_v/F_m、Yield、ETR和qP随温度升高而下降，qN则相反，藻体光合活性和固碳效率在26℃下达到最高，且与28℃和30℃的差异显著（P<0.05，n=3）。藻体的SGR、F_v/F_m、Yield、ETR和qP随光照强度升高呈先上升后下降的变化趋势，qN则相反，且在18.75 μmol/（m²·s）弱光照下出现轻微光抑制，藻体生长、光合活性及固碳效率在光照强度25.00 μmol/（m²·s）时达到最高，但与18.75和31.25 μmol/（m²·s）的差异不显著（P>0.05，n=3）。因此，针叶蕨藻在27.5‰盐度、26℃和25.00 μmol/（m²·s）光照强度下生长最快且光合作用能力最高。

Abstract:

In order to explore the effects of environment factors on growth of Caulerpa sertularioides, the changes in growth and chlorophyll fluorescence parameters were studied under different salinity, temperature and light intensity. The results showed that the specific growth rate (SGR), maximum light quantum yield (F_v/F_m), actual photosynthetic efficiency (Yield), electron transfer rate (ETR) and photochemical quenching (qP) increased at first and then decrease with increasing salinity, while non-photochemical quenching (qN) was opposite. The photosynthetic activity and carbon fixation efficiency of the algae under 27.5‰ salinity were the highest, and there were significant difference with those under 25‰ and 30‰ salinity (P<0.05, n=3). The SGR, F_v/F_m, Yield,

ETR and qP of the algae decreased with temperature rising, and qN was opposite. The photosynthetic activity and carbon fixation efficiency of algae under 26℃ were the highest, and there were significant difference with those under 28℃ and 30℃ (P<0.05, n=3). The SGR, F_v/F_m, Yield, ETR and qP of the algae increased at first and then decreased with increment of light intensity, while qN was opposite, and there was slight photoinhibition under 18.75 μmol/(m²·s) light intensity. The growth, photosynthetic activity and carbon fixation efficiency of algae were the highest under 25.00 μmol/(m²·s) light intensity, but no significant difference with those under 18.75 and 27.5 μmol/(m²·s) light intensity (P>0.05, n=3). Therefore, it was suggested that C. sertularioides could grow fast with high photosynthesis ability under the conditions of 27.5‰ salinity, 26℃, and 25.00 μmol/(m²·s) light intensity.