几种典型氮源加富培养对胶州湾浮游植物群落结构的影响

陆源输入氮源对近岸海域浮游植物生态系统有至关重要的作用。为了解胶州湾海域浮游植物对不同陆源输入氮源的响应，本研究于2020年秋季在青岛近海海域进行了现场加富实验，并通过显微镜镜检和矩阵因子化程序(CHEMTAX)分析了不同氮源加富培养对胶州湾浮游植物群落结构的影响。结果表明，单一氮源对浮游植物细胞生长的促进作用表现为尿素(CH₄N₂O)>氯化铵(NH₄Cl)>硝酸钠(NaNO₃)；李村河河水中的复合氮源极显著地促进了浮游植物的生长(P<0.01)；氮源加富培养后，胶州湾海域优势种由甲藻(Pyrrophyta)演替为硅藻(Bacillariophyta)；显微镜镜检结果与CHEMTAX分析结果的线性回归分析显示，在不同氮源培养体系中，甲藻细胞丰度与Chl a生物量呈显著正相关关系(r=0.656,P<0.05)，硅藻细胞丰度与Chl a生物量呈极显著正相关关系(r=0.674,P<0.01)；浮游植物对溶解有机氮(DON)的利用率大于溶解无机氮(DIN)，对复合氮源的利用...

Effects of enrichment culture of several typical nitrogen sources on phytoplankton community structure in Jiaozhou bay

Abstact: Terrestrial nitrogen input plays an important role in the phytoplankton ecosystem of coastal waters. To understand the response of the phytoplankton of Jiaozhou bay to the input of different nitrogen sources, an on-site enrichment experiment was carried out in coastal water of Qingdao in the autumn of 2020. The effects of enrichment culture of different nitrogen sources on phytoplankton community structure in Jiaozhou bay were analyzed by microscope and CHEMTAX method. The promoting effect of single nitrogen source on phytoplankton cell growth was CH₄N₂O>NH₄Cl>NaNO₃. The compound nitrogen source in Licun river significantly promoted the growth of phytoplankton (P<0.01). After enrichment culture of nitrogen source, the dominant species will evolve from Pyrrophyta to Bacillariophyta. The results of microscopic examination and CHEMTAX showed that there was a very significant positive correlation between Pyrrophyta cell abundance and Chl a biomass (r=0.656, P<0.01) and there was a significant positive correlation between Bacillariophyta cell abundance and Chl a biomass (r=0.674, P<0.01) in different nitrogen source culture systems; The utilization rate of phytoplankton to DON is greater than DIN, and the utilization rate of compound nitrogen source is greater than that of single nitrogen source. This study clarified the effects of several typical nitrogen source inputs on the dominant species of phytoplankton in Jiaozhou bay, provides a theoretical reference for the development and utilization of marine biological resources, and provides a theoretical basis for the protection of marine ecological environment in coastal waters.