海洋硅藻对不同氮源及氮磷比的生理学响应  

Physiological Responses of Marine Diatom to Different Nitrogen Sources and N/P Ratios

作　　者：吴亚平 贾非 侯睿 李伟[3] WU Yaping;JIA Fei;HOU Rui;LI Wei(School of Marine Science and Fisheries,Jiangsu Ocean University,Lianyungang 222005;Su Li Environmental Technology Co.,Ltd.,Nanjing 210029,China;School of Life and Environment Sciences,Huangshan University,Huangshan 245021,China)

机构地区：[1]江苏海洋大学海洋科学与水产学院,江苏连云港222005 [2]江苏省苏力环境科技有限责任公司,江苏南京210029 [3]黄山学院生命与环境科学学院,安徽黄山245021

出　　处：《江苏海洋大学学报（自然科学版）》2023年第2期30-38,共9页Journal of Jiangsu Ocean University:Natural Science Edition

基　　金：国家自然科学基金资助项目(41876113);江苏省高等学校基础科学(自然科学)研究重大项目(21KJA170001);江苏省高校“青蓝工程”资助项目。

摘　　要：近海,特别是河口区域,氮营养盐形态多样,且氮磷营养盐比例变化幅度大,对近海浮游植物的生理过程有着明显的调控作用。以河口常见硅藻三角褐指藻为研究对象,培养于不同形态氮及氮磷比营养盐中,发现三角褐指藻均在第4天进入对数生长期,细胞浓度快速增加,并在第8至第9天达到峰值,对应的藻液pH也呈现相同模式。在生长初期,NH_(4)^(+)为氮源的比生长速率明显比NO_(3)^(-)处理组高,而在生长的中后期阶段,NH_(4)^(+)处理组的三角褐指藻生长速度下降更快。在生长初期至平台期,细胞的光化学效率及光合参数未受氮源和氮磷比的影响,而在氮磷比(物质的量比)为64∶1,即磷限制时,比生长速率和各项光合生理参数,如最大电子传递速率rETR_(max)、光饱和点I_(k)和光能利用效率α,在生长各阶段均出现显著下降。结果表明,铵盐对硅藻初期生长的促进作用更为显著,当细胞浓度达到平台期后,不同形态氮处理间差异很小。另外,虽然消亡期细胞浓度下降幅度很小,但rETR_(max)与光能利用效率却明显降低,说明这两种参数可作为关键指标来判断藻华所处生长周期。Offshore,especially in the estuary area,the concentration and ratios of nitrogen and phosphorus nutrient vary a lot,which plays an important role in mediating the physiology of phytoplankton.Phaeodactylum tricornutum was cultured under different nitrogen sources and N/P ratios that simulated the conditions of estuarine areas.Results showed that cells entered into the logarithmic phase since the 4 th day,with cell concentration increased rapidly,and reached peak values between the 8 th to 9 th day,the corresponding pH value showed similar pattern as algal culture.In the early stage,the growth rate of cells with NH_(4)^(+) as the N source was significantly higher than that of the NO_(3)^(-) treatment,while in the middle and late stage,the growth rate of the NH_(4)^(+) treatment decreased faster.From the early to the plateau stage,the photosynthetic parameters of the cells were not affected by the N/P ratios,while the growth rate and various photosynthetic physiological parameters,such as the maximum electron transport rate(rETR_(max)),light saturation point(I_(k))and light utilization efficiency(α),were all significantly decreased when N/P was 64∶1.The results showed that ammonium promoted the growth of diatoms more significantly than nitrate in the early stage,while no significant difference between nitrogen forms in the plateau stage.In addition,although the decline of cell concentration in the decay stage was small,rETR_(max) and light utilization efficiency were significantly reduced,indicating that these two parameters can be used as key indicators to determined the growth stage of algal blooms.

关 键 词：三角褐指藻 营养盐 氮磷比 光合作用 

分 类 号：X173[环境科学与工程—环境科学]