| 引用本文: | 谭啸,石琳,段志鹏,曾庆飞,李聂贵,强娟.氮磷比对微囊藻与栅藻磷赋存及分配的影响.湖泊科学,2022,34(5):1461-1470. DOI:10.18307/2022.0505 |
| Tan Xiao,Shi Lin,Duan Zhipeng,Zeng Qingfei,Li Niegui,Qiang Juan.Influence of N ∶P ratio on the phosphorus accumulation and distribution of Microcystis and Scenedesmus. J. Lake Sci.2022,34(5):1461-1470. DOI:10.18307/2022.0505 |
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| 摘要: |
| 太湖水体氮浓度及氮磷比的改变可能影响藻类对磷元素的赋存及分配，进而影响水体总磷浓度. 为此，本研究选取常见蓝藻(群体微囊藻和单细胞微囊藻)和绿藻(斜生栅藻)，设置低氮磷比(N ∶P=2)和高氮磷比(N ∶P=20)培养实验，分析藻体胞内磷(INT-P)和胞外磷(EPS-P)含量、形态及分布，探究氮磷比对藻体磷元素赋存及分配的影响. 结果表明：低氮磷比组斜生栅藻和群体微囊藻的藻体磷(CTP，即INT-P与EPS-P之和)显著增加，分别为高氮磷比组的2.7和1.4倍. 斜生栅藻和群体微囊藻EPS-P含量(约占CTP的80%)分别增加了3.1和0.48倍，而INT-P含量对氮磷比无明显响应. 低氮磷比组的斜生栅藻和群体微囊藻EPS含量分别增加了51.7% 和63.5%. 此外，微囊藻的CTP与EPS-P主要以可交换态活性磷存在，而INT-P主要以铁铝结合态磷存在. 本研究发现低氮磷比促进了藻类EPS分泌，导致EPS-P升高，显著增加了藻体颗粒态磷的含量. 这或许是近年来太湖水体总磷波动的原因之一. |
| 关键词: 微囊藻 栅藻 氮磷比 磷分配 胞外聚合物 太湖 |
| DOI：10.18307/2022.0505 |
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| 基金项目:国家自然科学基金项目(32071569)、中央高校科研业务费项目(B210202010)、2020年度院级科研仪器设备研制项目(YJKYYQ20200048)和中国博士后基金项目(2020M681472)联合资助 |
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| Influence of N ∶P ratio on the phosphorus accumulation and distribution of Microcystis and Scenedesmus |
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Tan Xiao1, Shi Lin1, Duan Zhipeng1,2, Zeng Qingfei3, Li Niegui4, Qiang Juan5
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1.Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210024, P. R. China;2.College of Hydrology and Water Resources, Hohai University, Nanjing 210024, P. R. China;3.State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;4.Nanjing Institute of Water Conservancy and Hydrology Automation, Ministry of Water Resources, Nanjing 210012, P. R. China;5.Water Resources Bureau of Wujin District in Changzhou City, Changzhou 213115, P. R. China
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| Abstract: |
| Variations of nitrogen (N) concentration and the ratio of N to phosphorus (P) in Lake Taihu may impact P accumulation and allocation of algal cells, and even influence total P concentration in water. In this study, common cyanobacteria (colonial and unicellular Microcystis strains) and a green alga (Scenedesmus obliquus) were cultured in different N ∶P groups (N ∶P=2 and N ∶P=20). Changes in their P forms, content, and distribution (intracellular P (INT-P) and extracellular P (EPS-P)) were explored. Results showed that the total cellular P contents (CTP, including INT-P and EPS-P) of S. obliquus and colonial Microcystis in the low N ∶P group were 2.7 and 1.4 times higher than those in the high N ∶P group, respectively. In the low N ∶P group, EPS-P occupied about 80% of the CTP. Particularly, EPS-P contents of the low-N ∶P treated S. obliquus and colonial Microcystis increased by 3.1 and 0.48 times higher than those of the high N ∶P group. In the low N ∶P groups, EPS content of S. obliquus and colonial Microcystis increased by 51.7% and 63.5%, respectively. However, changes of INT-P were not significant in both species. Moreover, CTP and EPS-P mainly existed as NH4Cl-P, while INT-P was mainly found as Fe/Al-P. These findings revealed that low N ∶P ratio affects the P accumulation and distribution patterns of algal cells, by promoting EPS secretion and EPS-P accumulation. It may be a potential reason for total P fluctuation in the water of Lake Taihu. |
| Key words: Microcystis Scenedesmus nitrogen to phosphorus ratio phosphorus allocation extracellular polymeric substances Lake Taihu |
