稀土元素La(Ⅲ)对铜绿微囊藻生长和生理特性的影响  

Effects of La(Ⅲ)on Growth and Physiological Characteristics of Microcystis aeruginosa

作　　者：卢桂蓉 王应军 范子奇 Lu Guirong;Wang Yingjun;Fan Ziqi(College of Environmental Sciences,Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]四川农业大学环境学院,成都611130

出　　处：《生态毒理学报》2021年第6期256-267,共12页Asian Journal of Ecotoxicology

摘　　要：为了解在营养元素氮、磷限制环境下稀土元素镧(La)对贫营养水体中铜绿微囊藻的影响及作用机制。在实验室模拟培养下,研究稀土元素镧对铜绿微囊藻(Microcystis aeruginosa)生长和生理特性的影响,测定缺素胁迫和正常情况不同La^(3+)浓度对藻的生长量、叶绿素a、可溶性糖、可溶性蛋白、抗氧化酶活性(过氧化氢酶(CAT)、过氧化物酶(POD)以及丙二醛(MDA)含量的影响。结果表明,在缺磷胁迫下,低浓度La^(3+)(0.10~0.20 mg·L^(-1))能刺激铜绿微囊藻的生长,增强光合作用效率,提高抗氧化酶活性;随着处理浓度的提高和处理时间的延长,藻类生长受到抑制,表现为光合色素、可溶性蛋白含量明显下降,可溶性糖含量增加,膜质过氧化程度加重。与正常情况的培养相比,在缺磷胁迫下,铜绿微囊藻对La^(3+)的耐受力明显降低;而在缺氮情况下,La^(3+)不能维持微囊藻的正常生长代谢。因此,一定浓度范围的稀土元素镧对缺磷及正常情况下的铜绿微囊藻生长有促进作用,是引起贫营养水体中铜绿微囊藻大量繁殖的诱因之一。In order to understand the effect and mechanism of rare earth element lanthanum(La)on Microcystes aeruginosa in oligotrophic water under the limit environment of nutrient elements nitrogen and phosphorus.Under simulated cultivation in the laboratory,the effects of lanthanum on the growth and physiological characteristics of Microcystis aeruginosa were studied.The effects of different La^(3+)concentrations on the growth of algae,the contents of chlorophyll a,soluble sugar and soluble protein,the activity of antioxidant enzymes(catalase(CAT)and peroxidase(POD)),and the content of malondialdehyde(MDA),under nutrient deficiency stress and normal conditions were measured.The results showed that under phosphorus deficiency stress,low concentration of La^(3+)(0.10~0.20 mg·L^(-1))could stimulate the growth of Microcystis aeruginosa,enhance the photosynthetic efficiency and the activity of antioxidant enzymes.With the increase of treatment concentration and the extension of treatment time,the growth of algae was inhibited,the contents of photosynthetic pigment and soluble protein were obviously decreased,the content of soluble sugar was increased,and the degree of membrane peroxidation was aggravated.Compared with the normal culture,the tolerance of Microcystis aeruginosa to La^(3+)was significantly reduced under phosphorus deficiency stress.Microcystis aeruginosa could not maintain the normal growth and metabolism under the condition of nitrogen deficiency with La^(3+).Therefore,lanthanum in a certain concentration range can promote the growth of Microcystis aeruginosa in phosphorus deficiency and normal conditions,and is one of the inducements for the proliferation of Microcystis aeruginosa in oligotrophic water.

关 键 词：磷 氮 稀土元素 镧 铜绿微囊藻 生理特性 

分 类 号：X171.5[环境科学与工程—环境科学]