环境因子对小球藻(Chlorella sp. XQ-20044)光合作用的影响

小球藻（Chlorella sp.XQ-20044）是一株具有应用潜力的产油微藻，本文利用测定净光合放氧速率的方法研究了光照强度、温度、pH值和盐度对其光合作用的影响。研究结果表明：小球藻适宜的光照强度为500~1200 μmol·m^-2·s^-1，光补偿点约30 μmol·m^-2·s^-1，光饱和点在600 μmol·m^-2·s^-1附近；光合作用适宜的温度范围为30~42.5℃，最适温度为40℃；适宜的pH值范围7.0~10.0，最适pH值为8.0；适宜盐度范围0.1~0.3 mol/L，最适盐度为0.2 mol/L。从光合作用特性来看，小球藻能适应较强的光照强度、较高的温度、偏碱性和较高的盐度环境，其中可耐受较高盐度的特性，有助于预防敌害生物的污染，对于实现规模培养，特别是利用开放系统进行规模培养较为有利。

Effects of Environmental Factors on the Photosynthesis of Chlorella sp. XQ-20044

Chlorella sp. XQ-20044 is a lipid-rich strain with potential application in microalgal biodiesel. In this study, the effects of light intensity, temperature, pH and salinity on photosynthesis were studied by measuring net photosynthetic O₂ evolution. Suitable light intensities for this Chlorella species ranged from 500 to 1200 μmol·m^-2·s^-1, and saturation light intensity was around 600 μmol·m^-2·s^-1. The appropriate temperatures for photosynthesis were in the range of 30℃ to 42.5℃, with the optimal temperature of 40℃. Suitable pH values ranged from 7.0 to 10.0, and the optimum pH value was 8.0, and salinity concentrations ranged from 0.1-0.3 mol/L, with an optimal salinity of 0.2 mol/L for photosynthesis of this strain. Based on its photosynthetic features, Chlorella sp. XQ-20044 can adapt to strong light intensity, high temperature, high salinity, and slightly alkaline conditions. The adaptation to high salinity is helpful to prevent culture from predator contamination, and is propitious to mass culture of this alga, especially large-scale production with open photo bioreactors. Our results provide a technological basis for the optimization of culture conditions.