| 引用本文: | 许海,陈洁,朱广伟,秦伯强,张运林.水体氮、磷营养盐水平对蓝藻优势形成的影响.湖泊科学,2019,31(5):1239-1247. DOI:10.18307/2019.0518 |
| XU Hai,CHEN Jie,ZHU Guangwei,QIN Boqiang,ZHANG Yunlin.Effect of concentrations of phosphorus and nitrogen on the dominance of cyanobacteria. J. Lake Sci.2019,31(5):1239-1247. DOI:10.18307/2019.0518 |
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| 摘要: |
| 以江苏省南京市富营养化程度不同的清溪、护城河、玄武湖、月牙湖、琵琶湖和前湖为研究对象，调查各水体浮游植物的群落特征和优势种，并结合藻类生长潜力试验，探究不同氮、磷营养水平的自然水体对铜绿微囊藻（Microcystis aeruginosa）和斜生栅藻（Scenedesmus obliquus）生长与竞争的影响.野外调查发现不同营养水平水体浮游植物优势种不同，按水体富营养化程度从高到底依次以绿藻、蓝藻、硅藻和隐藻分别占优势.单一藻种培养时，铜绿微囊藻在清溪、护城河和玄武湖水体中生长均较好，而斜生栅藻仅在高氮、磷浓度的清溪和护城河水体中有较大生长量，说明斜生栅藻对氮、磷的需求高于铜绿微囊藻；两种藻共培养时，清溪水体中斜生栅藻占优势，护城河和玄武湖水体中铜绿微囊藻占优势，但其他水体中两种藻均不能生长，说明氮、磷浓度过高或过低都不利于蓝藻形成优势.对低营养水平的玄武湖、琵琶湖、月牙湖和前湖水体进行氮、磷加富后，两种藻均能较好地生长，且各组没有显著差异，说明藻类在这些水体中生长受到氮、磷的限制，氮、磷浓度升高会增加水华发生的风险.本研究将野外调查和藻类生长潜力实验相结合，深入探究了蓝藻优势形成与水体氮、磷营养水平的关系，揭示了蓝藻水华是湖泊富营养化发展到特定阶段的产物，水体氮、磷浓度过高或过低均不易产生蓝藻优势. |
| 关键词: 浮游植物 优势种 蓝藻 藻类生长潜力实验 营养盐限制 |
| DOI：10.18307/2019.0518 |
| 分类号: |
| 基金项目:国家自然科学基金项目（41573076）、中国科学院前沿科学重点研究项目（QYZDJ-SSW-DQC008）、国家水体污染控制与治理科技重大专项（2017ZX07203-001）和中国科学院南京地理与湖泊研究所“一三五”战略发展规划项目（NIGLAS2017GH04）联合资助. |
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| Effect of concentrations of phosphorus and nitrogen on the dominance of cyanobacteria |
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XU Hai1, CHEN Jie1,2, ZHU Guangwei1, QIN Boqiang1, ZHANG Yunlin1
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1.State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;2.School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, P. R. China
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| Abstract: |
| Six lakes (rivers) in Nanjing, Jiangsu Province, with different nutrient levels, were investigated for the phytoplankton community and dominant species. They were Qingxi River, Hucheng River, Xuanwu Lake, Yueya Lake, Pipa Lake, Qianhu Lake. At the same time, algae growth potential tests (AGP tests) were conducted to examine the growth and competition characteristics of Microcystis aeruginosa and Scenedesmus obliquus in different water bodies. Field investigation found that water bodies with different nitrogen (N) and phosphorus (P) concentration have different dominant species. According to nutrient level of water bodies, Chlorophyta, Cyanophyta, Bacillariophyta and Cryptophyta appeared in sequence as dominant species. When cultured with a single algae species, M. aeruginosa grew better in water bodies collected from Qingxi River, Hucheng River and Xuanwu Lake; while S. obliquus only showed a large maximal cell density when cultured in water with high nutrient levels collected from Qingxi River and Hucheng River. It indicated that N and P demand of S. obliquus may be higher than that of M. aeruginosa. When cultured with multi-species, S. obliquus dominated in water body of Qingxi River, and M. aeruginosa dominated in water body of Xuanwu Lake. But the algae could not grow in other water bodies. It indicated that cyanobacteria will not be dominant phytoplankton in waters with too high or too low N and P concentrations. N and P enrichment experiments were conducted using water from Xuanwu Lake, Hucheng River, Yueya Lake and Qianhu Lake, whitch had low N and P levels. The concentrations of N and P would influence the growth of algae, while the concentrations increased, the risk of blooms would increase. Through field investigation and AGP text to explore the relationship between the formation of cyanobacteria and the level of nutrient in water, which provided a scientific basis for revealing the cyanobacteria bloom is the product of eutrophication lake to a certain stage. It is difficult to produce cyanobacteria bloom with too low or too high N and P concentrations. |
| Key words: Phytoplankton dominate algae species cyanobacteria algae growth potential tests nutrient limination |
