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近来许多研究表明，不论是在无机氮丰富还是贫乏的水域，铁元素的供应对于浮游植物的生物量、生长率、种类组成及初级生产力均会产生影响．通过室内培养，研究了铁对三角褐指藻生长、光合作用以及细胞生化组成的影响．实验结果表明，在其他营养盐充足的条件下，海水中铁浓度的变化对三角褐指藻的生长及光合作用均有显著影响．在５×１０－７ｍｏｌ／ｄｍ３铁浓度时，三角褐指藻可达到其最大光合作用速率．在添加铁的条件下，三角褐指藻细胞多种生化组成受到不同程度的影响，其中叶绿素ａ含量变化幅度最大，增加了２５％～３５％，叶绿素ｃ、类胡萝卜素含量也有一定程度的增加，但增长幅度要小于叶绿素ａ；碳水化合物的含量增加了５％～１０％，蛋白质含量的增加幅度在５％～１５％之间；超氧化物歧化酶（ＳＯＤ）的活性及ＤＣＭＵ荧光增强比（Ｆｄ／Ｆ）也呈明显的增加趋势．铁是海洋初级生产过程中的一种限制因子．
Recently, many studies show that the supply of iron can affect phytoplankton biomass, growth rate, species composition and primary productivity, whether in areas rich or poor in inorganic nitrogen. The effects of iron on the growth, photosynthesis and biochemical composition of Phaeodactylum tricornutum were studied through laboratory culture. The experimental results showed that under the condition of sufficient nutrients, the change of iron concentration in seawater had a significant effect on the growth and photosynthesis of Phaeodactylum tricornutum. At 5 × 10-7mol / dm3 iron concentration, Phaeodactylum tricornutum can reach its maximum photosynthesis rate. Under the conditions of adding iron, the biochemical composition of Phaeodactylum tricornutum cells were affected to varying degrees, of which the content of chlorophyll a changed the most, increased by 25% -35%, and the content of chlorophyll c and carotenoid also increased to a certain extent , But the growth rate was less than that of chlorophyll a; the content of carbohydrate increased by 5% -10% and the content of protein increased by 5% -15%; the activity of superoxide dismutase (SOD) (Fd / F) also showed a significant upward trend. Iron is a limiting factor in primary ocean production.