葡萄糖添加对太湖水体浮游植物生长的影响

为探索葡萄糖(碳源)添加对浮游植物生长的影响,于2015年7月30日—8月6日用太湖梅梁湾水体进行了碳、氮、磷的营养盐添加试验。试验设置3个处理,每个处理均添加相同水平的氮、磷营养盐,而碳添加质量浓度分别为0 mg/L(对照组)、51 mg/L(低碳组)和102 mg/L(高碳组)。结果显示,对照组与低碳组的叶绿素a(Chl-a)均显著高于高碳组(P0.05),3个处理间总悬浮颗粒物(TSS)质量浓度没有显著差异(P0.05);整体上,第1~8天和第6~8天,高碳组的硝酸盐氮(NO_3~--N)、活性磷(SRP)质量浓度的降低速率均是最高的,低碳组次之,对照组最慢(P0.05)。研究表明,葡萄糖添加控制了浮游植物生长,促进了水体中无机氮、磷质量浓度降低;但在添加葡萄糖的处理中,无机氮、磷质量浓度降低速度的加快并没有得到更高的浮游植物浓度。

Effect of glucose addition on the growth of phytoplankton from Lake Taihu

In order to find out the effect of glucose as a carbon source on the growth of phytoplankton, an experiment on carbon,nitrogen and phosphorus enrichment to water from Lake Taihu was carried out on the shore of Meiliang Bay,Lake Taihu,during 30 July to 6 August,2015.Three treatment groups were set,in which the nitrogen and phosphorus enrichments were the same,and the gradient carbon enrichments were respectively 0 mg/L (the Control group),51 mg/L (Low Carbon treatment) and 102 mg/L (High Carbon treatment).The results were that the Chl-a of the Control and Low Carbon treatment were significantly higher than that of High Carbon treatment ( P<0.05) ,and the concentrations of TSS were not significantly different from each other in the three treatments (P>0.05).From day 1 to day 8 and from day 6 to day 8,the reduction rate of SRP and NO-3-N concentrations in High Carbon treatment was the highest,then came the Low Carbon treatment,and the rate in the Control was the slowest (P<0.05).The results showed that glucose addition exerted a controlling effect on the growth of phytoplankton, mainly through promoting the reduction of inorganic nitrogen and phosphorus concentrations in the water, but the acceleration of the reduction rate did not result in a higher concentration of phytoplankton.