春季太湖梅梁湾水体中藻类光量子产额的变化规律

藻类光量子产额是表征藻类对环境因素响应的重要参数之一.利用中国科学院太湖生态网络站栈桥头测定的水体初级生产力及水下辐照度数据,计算了4个观测时段藻类的光量子产额,结果表明,自表层至30 cm处,藻类的光量子产额随深度基本呈现线性增加的趋势,但随深度的进一步增加,光量子产额增加的趋势变缓,直至接近于平直状态(在到60～80 cm之间),该最大值也基本为0.12 mol(O2)/mol(光子),且该处的光量子产额是表层的10倍左右.春季,在太湖梅梁湾60 cm以上,光并不是藻类生长的限制条件,而在60 cm以下,由于光的衰减,使得光成为限制其光合作用的条件.

The law of variation of light quantum yield of Algal in Meiliang Bay of Taihu Lake in spring

The light quantum yield of algae particles is one of the important parameters characterizing the algae response to the environmental factors. Based on the water primary productivity and underwater irradiance at the head of the jetty as a station of the Taihu Ecological Network of the Academia Sinica the light quantum yields of algal were calculated for four observational times. Results suggest that the yields increased basically in a linear way from the just below surface down to 30 cm but further downward the yield increases were slowed down and between 60 and 80 cm the yields were level off, where the maxima were 0.12 mol (O2) /mol (photon), figures that were about 10 times those just below the surface. In spring above 60 cm in Meiliang Bay light was not a constraint of algal growing but under 60cm light was the limiting factor to photosynthesis due to light attenuation.