光照强度对浮游植物丰度及吸收铁的影响1）

摘要

We collected water samples, filtered planktonic animal, cultured the phytoplankton in the Small Xingkai Lake for 12 d in the laboratory.We set four light gradients and five different Fe concentrations by comparative experiments.With the increase of Fe concentration, absorption of phytoplankton on Fe increased correspondingly.In low light intensity, the ab-sorption amount of Fe had no regular law.In 4 000 lx of light intensity, the phytoplankton abundance reduced by 63.6 ind/L in 0 of phytoplankton Fe uptake.In 8 000 lx, the phytoplankton abundance was positively correlated with Fe uptake.In 12 000 lx, the phytoplankton abundance increased by 2 791.2 ind/L in 0.091 mg/L of Fe uptake.The light intensity on the restriction of algae growth in nutrient solution culture was more obvious in the algae growth restriction.%在小兴凯湖采集水样，滤掉浮游动物，对浮游植物进行为期12 d的实验室培养。试验设置了4个光照梯度和5个Fe浓度，分别进行对比试验。结果表明：随着Fe浓度的增加，浮游植物对Fe的吸收量也相应的增加。在低光照强度下，浮游植物对Fe的吸收规律不明显。在光强为4000 lx时，浮游植物吸收Fe量为0的培养瓶中浮游植物丰度降低了63．6 ind· L－1。在光强为8000 lx条件下，浮游植物丰度与吸收Fe量呈正相关关系。在光强为12000 lx时，吸收Fe量为0．091 mg· L－1的培养瓶中浮游植物丰度增加了2791．2 ind· L－1，说明了光照强度对藻类生长的限制作用明显高于培养液中营养元素对藻类生长的限制作用。