海洋浮游植物对硒的摄取和转化

Uptake and transformation of selenium by marine phytoplankton

本文研究海洋浮游植物生长过程对硒的摄取和转化。结果表明，在藻类生长初期，快速选择摄取Se（Ⅳ），并积累于藻相。在指数生长期，以溶解有机物形式排出体内多余硒。在稳定生长期各形态硒基本趋于稳定。藻类混种培养能提高对Se（Ⅳ）的摄取程度及溶解有机硒代谢速度。混种培养之稳定生长期，Se（Ⅳ），Se（Ⅵ），溶解有机硒，藻相Se含量分别占总硒量之1．0％，10．2％，28．1％，60．6％。Se（Ⅳ）／Se（Ⅵ）值为0．10。溶解有机硒／总溶解硒值为0．71，与天然海区现场调查结果相接近。

Uptake and transformation of Se during the entire growth of three marine phytoplankton have been bserved. The results show that selective uptake of Se(Ⅳ)and accumulation of Se in algal phase are rapid in the 1st to 2nd day of culture. Excess selenium in algal phase is excreted in the frm of dissolved organic selenium during the exponential phase.Distribution of Se frms in culture medium keeps cnstant substantially during the stationary phase.Uptake level of Se(Ⅳ) in multiple species culture is higher than in single species culture.Percentages of content of Se(Ⅳ),Se (Ⅵ), org-Se and algal phase Se in ttal selenium content are 1.0 %, 10. 2 %, 28. 1 %, 6. 6 %, respectively. Ratios of Se(Ⅳ)/Se(Ⅵ) and rg-Se/D-Se are about 0. 10 and 0. 70, respectively. The results are appraching to that of field observations in natural marine environment.