不同磷条件下高温胁迫对铜绿微囊藻生长的影响及恢复研究

发布时间：2017-12-31 01:36

本文关键词：不同磷条件下高温胁迫对铜绿微囊藻生长的影响及恢复研究　出处：《南京信息工程大学》2015年硕士论文　论文类型：学位论文

【摘要】：在蓝藻水华多发的夏季,水体温度和区域气温往往在30～40℃,并且连续数日的高温天气均有出现。通过对藻类补偿作用进行研究,了解其在胁迫条件下的生长及恢复规律对于探索蓝藻暴发条件具有重要的生态意义,对于城市湖泊和水库有重要的应用价值。本文以铜绿微囊藻(Microcystis aeruginosa)为材料,研究了低磷(0.05mg·L-1)、中磷(0.50mg·L-1)和高磷(500mg·L-1)三种条件下高温胁迫下的生长和恢复状况。以25℃为对照,设置35℃和40℃高温,分别处理3d、6d和12d后转入正常温度培养30d,测定生长过程中的细胞密度、色素含量、丙二醛和酶活性。主要研究结论如下：(1)高温胁迫阶段,不同磷条件下铜绿微囊藻的生长状况不同。35℃高温胁迫下,随磷浓度的增加,高温对细胞增殖的抑制作用增强,低磷、中磷和高磷三种条件下,胁迫第12d时,叶绿素a含量分别比对照组下降了29.03%、24.49%和22.27%,类胡萝卜素合成并未受到显著抑制：抗氧化酶活性升高,胁迫时间越长,丙二醛含量越高。40℃高温胁迫下,细胞密度和色素合成均受到显著抑制,胁迫时间越长,细胞受损越严重。(2)恢复培养阶段,不同磷条件下铜绿微囊藻的恢复生长状况与补偿效果不同。35℃胁迫解除后,低磷条件下,6d和12d组的细胞密度呈现超补偿,30d平均补偿指数Gm/Cm分别为1.27和1.20；中磷条件下,6d和12d组的细胞密度呈现超补偿,各组叶绿素a含量均呈现超补偿,其中6d组最为突出；高磷条件下,3d和6d组的色素含量呈现超补偿。40℃胁迫解除后,中磷条件下,6d组的细胞密度和叶绿素a呈现超补偿；高磷条件下,3d组的细胞密度和类胡萝卜素呈现超补偿,胁迫时间越长,补偿效果越差。(3)铜绿微囊藻细胞的恢复状况与抗氧化系统的抵御和恢复能力有密切关系。35℃胁迫时间越长,恢复培养阶段丙二醛含量越高,适宜的磷营养有利于细胞膜功能的恢复。低磷和中磷条件下,35℃胁迫时间越长,酶活性越高；高磷条件下,6d组酶活性较高。40℃胁迫解除后,低磷条件下丙二醛含量和酶活性总体表现为6d组12d组3d组；中磷和高磷条件下,胁迫时间越长,丙二醛含量越高,胁迫时间较短(3d)有利于抗氧化系统的恢复。(4)通过Logistic模型,对铜绿微囊藻细胞的生长曲线进行了模拟和参数分析。35℃处理组表现为磷浓度越高,环境容纳量越大,tp越晚,r越低；40℃处理组表现为磷浓度越高,细胞密度越大,环境容纳量越大。对于35℃高温胁迫,低磷条件下处理6d、中磷条件下处理12d和高磷条件下处理6d,会引起超补偿效应,而高磷条件下处理3d会导致更大程度的超补偿。对于40℃高温胁迫,中磷条件下处理6d、高磷条件下处理3d和6d,会引起超补偿效应,6d组预计39d后超过3d组,在更长时间上达到更多的细胞数目。高温诱发超补偿生长与自然界中藻类暴发的过程存在相似性,这种生物内源性因素及藻体生理特征的变化进一步为湖泊水华发生的理论研究提供依据。
[Abstract]:Multiple algal blooms in the summer, the water temperature and air temperature in the region often 30 to 40 DEG C, and the number of consecutive days of high temperature weather have appeared. Through the study of algae compensation, understand its growth under stress conditions and restoration of blue-green algae to explore conditions has important ecological significance, has important application value for the city of lakes and reservoirs. In this paper, Microcystis aeruginosa (Microcystis aeruginosa) as material, the effect of low phosphorus (0.05mg, L-1), P (0.50mg - L-1) and high phosphorus (500mg, L-1) under the three conditions under high temperature stress on growth and recovery. By 25 DEG C as control, set the 35 degrees and 40 degrees high temperature, respectively 3D, 6D and 12D then transferred to normal temperature 30d culture, growth process in the determination of cell density, pigment content, MDA content and enzyme activity. The main conclusions are as follows: (1) Gao Wenxie forced stage, under the condition of different phosphorus copper The growth status of green Microcystis in different high temperature.35 degrees of stress, with the increase of phosphorus concentration, inhibition effect of high temperature on cell proliferation enhancement, low phosphorus, phosphorus and high phosphorus under the three conditions, the 12D stress, the content of chlorophyll a were higher than the control group decreased by 29.03%, 24.49% and 22.27%, carotenoid the synthesis did not significantly inhibited the increased antioxidant enzyme activity, the longer the duration of stress, MDA content is higher.40 C under high temperature stress, the density of cells and pigment synthesis was inhibited significantly, the stress time was longer, the more serious of the damaged cells. (2) Hui Fupei raising stage, different phosphorus conditions of Microcystis aeruginosa growth recovery effect the status and compensation of different.35 C after stress relief, low phosphorus conditions, 6D and 12D. The cell density showed over compensation, 30d average compensation index of Gm/Cm were 1.27 and 1.20; in phosphorus conditions, 6D and 12D. The cell density showed over compensation, The content of chlorophyll a showed over compensation, which 6D group is most prominent; high phosphorus conditions, the pigment content of 3D and 6D groups showed compensatory.40 C releasing stress, phosphorus conditions, cell density and chlorophyll 6D group A showed overcompensation; high phosphorus conditions, cells in the 3D group. And carotenoid showed over compensation, the stress time was longer, the compensation effect is worse. (3) recovery and antioxidant system of Microcystis aeruginosa resistance and recovery capability is closely related to.35 DEG C stress time longer, recovery training stage MDA content is high, suitable for phosphorus nutrition is conducive to cell membrane function the recovery of low phosphorus and phosphorus. Under the condition of 35 DEG C, the stress time was longer, the higher the enzyme activity; high phosphorus conditions, high 6D enzymatic activity of.40 group C after removing stress under low P MDA content and enzyme activity in the overall performance of 6D group 12D group 3D group; middle and high phosphorus Under the condition of stress time, the higher the content of MDA, stress time shorter (3D) to the antioxidant system recovery. (4) through the Logistic model, the growth curve of Microcystis cells were simulated and parameters analysis of.35 treatment group showed higher phosphorus concentration, the greater the carrying capacity of the environment TP, later, the lower R; 40 treatment group showed higher phosphorus concentration, cell density, environmental capacity is greater. For the 35 high temperature stress, 6D treatment of low phosphorus conditions, 12D treatment and high phosphorus conditions in 6D phosphorus conditions, will cause the super compensation effect. While the high phosphorus conditions 3D can lead to excess compensation to a greater extent. For the 40 high temperature stress, 6D treatment in phosphorus conditions, 3D and 6D for treatment of high phosphorus conditions, will cause the super compensation effect, 6D group is expected after 39d than that in group 3D, the number of cells reached more in the longer time high. Induced compensatory growth It is similar to the process of algal blooms in nature. The variation of biological endogenous factors and physiological characteristics of algae will further provide theoretical basis for the theoretical research of Lake blooms.

【学位授予单位】：南京信息工程大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X52;X173

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