浮游藻类对POPs的吸附降解及其生理生态响应研究
发布时间：2018-12-15 04:51
【摘要】：持久性有机污染物(Persistent organic pollutants, POPs)和富营养化(eutrophication)是湖泊水体普遍面临的两大主要环境问题。富营养化带来的最明显的环境效应就是浮游藻类的大量繁殖,POPs的加入则会改变浮游藻类原本的生存环境,因此藻类的生长繁殖和生理机制必定会做出相应的改变。同时,POPs的亲脂疏水特性会使得这类污染物一旦进入到水体后亦极易被浮游藻体内的有机质所吸收,从而改变POPs在环境中的分布归趋。作为湖泊生态系统中最重要的初级生产者,浮游藻体一旦吸附了POPs之后再被更高一级的营养级作为能量和食物来源吸食,便会导致POPs的生物富集和生物放大效应,从而对水生生物产生严重危害。由此看来,浮游藻类是富营养化过程的结束点,同时也是POPs进行食物链传递的起点,因此,其可以看作是建立富营养化和POPs污染之间相互关系的节点和纽带。本文根据我国湖泊富营养状态下的优势浮游藻种(铜绿微囊藻(Microcystis aeruginosa)、斜生栅藻(Scenedesmus obliquus)和隐藻(Cryptomonas sp.)为载体,选取环境中典型POPs污染物质：菲(Phenanthrene)和αl-硫丹(a-Endosulfan)为目标物,通过室内模拟实验阐明浮游藻类与POPs污染的双向作用机制,丰富了对富营养化湖泊中POPs环境过程的认识,为湖泊POPs的污染控制提供理论依据。主要研究成果有如下几个方面：(1)研究菲与α-硫丹对铜绿微囊藻、斜生栅藻和隐藻的生长影响效应。结果表明：不同的污染物浓度对微藻产生了促进生长的兴奋效应模式和抑制生长的毒性效应模式,这种生长影响差异受到污染物品种和微藻种类差异影响,同时也与作用时间和作用浓度有关。低浓度的菲与α-硫丹对浮游藻类的生长产生了明显的促进作用,高浓度则有所抑制。菲对浮游藻类的生长刺激作用高于a-硫丹,两种污染物复合时的促进作用比单个化合物刺激时弱；斜生栅藻是最易被促进生长的藻种,其次为铜绿微囊藻,隐藻被刺激生长的反应则最弱。(2)探明浮游藻体的生理机制光合特性在菲与a-硫丹的外界刺激下发生的应激改变。当藻类生长环境受到威胁或改变时,其体内的最大和实际的光能转换率(Fv/Fm与Yield)也会随之发生变化并反映迅速：低浓度的菲与a-硫丹提高了微藻的最大和实际的光能转换率,其光合作用能力增强,高浓度则相反。斜生栅藻的光能转换率受影响增幅最大,其次为隐藻,而铜绿微囊藻相对最小。菲对藻体光合作用的提高要优于α-硫丹。浮游藻类的生长情况与光合作用变化显著相关,菲与α-硫丹通过提高浮游藻类的光合作用能力,影响藻体的生理机制发展,从而影响藻细胞的生长繁殖。(3)明确浮游微藻种类差异对目标污染物菲与α[-硫丹的差异吸附吸收和降解能力。结果表明：浮游藻类对水体中的菲与a-硫丹均有较强的吸附吸收作用和一定的降解能力。其中,铜绿微囊藻和斜生栅藻表现出较快的胞外吸附(Extracellular absorption)污染物速率,而隐藻则是在中期阶段对污染物在胞体内的吸收容量(Intracellular absorption)更多,这与隐藻细胞内较高的脂质含量有关。降解污染物方面,斜生栅藻对菲与α-硫丹同时表现出了最强的降解能力,但其对复合污染物的降解能力要低于对单个化合物的降解；而隐藻则能更好的降解复合污染物,且其对α-硫丹和低浓度的菲的降解率优于铜绿微囊藻,而高浓度的菲作用下,情况刚好相反。总的来说,藻体对污染物的降解能力随培养时间延长而逐渐升高,藻生物量越多以及后期死亡藻体数量越大越有利于浮游藻类对污染物的降解。
[Abstract]:Persistent organic pollutants (POPs) and eutrophic (Eutrophication) are two major environmental problems in lake water. The most obvious environmental effect brought by the eutrophication is the large number of planktonic algae, and the addition of the POPs can change the original living environment of the planktonic algae, so the growth and reproduction and the physiological mechanism of the algae are bound to make corresponding changes. At the same time, the lipophilicity and hydrophobic character of the POPs can be easily absorbed by the organic matter in the floating algae after the pollutant enters into the water body, thereby changing the distribution of the POPs in the environment. As the most important primary producer in the lake ecosystem, the floating algae can be used as energy and food source once the POPs are adsorbed, thus leading to the biological enrichment and the biological amplification effect of the POPs, thereby causing serious harm to the aquatic organism. As a result, the planktonic algae is the end point of the eutrophication process, and it is the starting point for the transfer of the food chain, so it can be regarded as a node and a link to establish the relationship between the eutrophication and the POPs pollution. This paper is based on the dominant algae species (Microcystis aeruginosa), Scenedesmus obliqueus and Cryptomonas sp. in the rich nutrition state of the lake in China.) The two-way action mechanism of the pollution of the planktonic algae and the POPs in the eutrophic lake is clarified by the indoor simulation experiment as the carrier, and the two-way action mechanism of the pollution of the planktonic algae and the POPs is clarified through the indoor simulation experiment, and the realization of the POPs environment process in the eutrophic lake is enriched, and provides a theoretical basis for the pollution control of the lake POPs. The main results of this study were as follows: (1) The effects of phenanthrene and sulfur-sulfur on the growth of microcystis aeruginosa, aslant and cryptoalgae were studied. The results showed that the different concentrations of pollutants had the effect of stimulating the growth of the microalga, and the effect of inhibiting the growth, which was influenced by the difference of the species of the pollutants and the species of the micro-algae, and also related to the time of action and the concentration of the action. The low concentration of phenanthrene and sulfur-sulfur can promote the growth of the planktonic algae, and the high concentration is inhibited. The effect of phenanthrene on the growth of planktonic algae is higher than that of a-sultan, and the promoting effect of the two pollutants is weaker than that of a single compound. (2) The physiological mechanism of the planktonic algae was found to change with the external stimuli of a-sultan. When the algae growth environment is threatened or changed, the maximum and actual photoenergy conversion rate (Fv/ Fm and yield) in the algae can also change and reflect the rapid: the low-concentration of the field of field and a-sulfur can increase the maximum and practical light energy conversion rate of the microalga, and the photosynthesis capacity of the algae is enhanced, the high concentration is the opposite. The light energy conversion rate of the oblique-green algae is the largest, followed by cryptococcus, and the microcystis aeruginosa is relatively minimal. The improvement of the photosynthesis of the algae is better than that of sulfur-sulfur. The growth of planktonic algae is related to the change of photosynthesis, and the growth and propagation of the algae cells are affected by increasing the photosynthetic capacity of the planktonic algae and the physiological mechanism of the algae. and (3) the difference of the species of the planktonic microalga on the difference of the species of the floating micro-algae on the adsorption and the degradation ability of the target pollutant phenanthrene and the arsenic[-sultan]. The results showed that the floating algae had a strong adsorption and absorption effect and a certain degradation ability to both the phenanthrene and a-sultan in the water. Among them, the microcystis aeruginosa and the oblique-grid algae exhibit a faster rate of extracellular absorption, while the cryptoalgae is more intensive to the absorption capacity of the pollutants in the cell at the medium-term stage, which is related to the higher lipid content in the cryptoalgae cells. in that aspect of the degradation of the pollutant, the oblique generation grid algae exhibit the strongest degradation capability at the same time, but the degradation ability of the compound pollutant is lower than the degradation of the single compound; and the cryptoalgae can better degrade the compound pollutant, and the degradation rate of the phenanthrene and the low-concentration phenanthrene is better than that of the microcystin, and the condition of the high-concentration phenanthrene is just the opposite. In general, the degradation ability of the algae to the pollutant gradually increases with the time of culture, the more the algae biomass and the higher the number of the late-dead algae, the more beneficial to the degradation of the planktonic algae on the contaminants.
【学位授予单位】：南京师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X524;X173
本文编号：2380012
[Abstract]:Persistent organic pollutants (POPs) and eutrophic (Eutrophication) are two major environmental problems in lake water. The most obvious environmental effect brought by the eutrophication is the large number of planktonic algae, and the addition of the POPs can change the original living environment of the planktonic algae, so the growth and reproduction and the physiological mechanism of the algae are bound to make corresponding changes. At the same time, the lipophilicity and hydrophobic character of the POPs can be easily absorbed by the organic matter in the floating algae after the pollutant enters into the water body, thereby changing the distribution of the POPs in the environment. As the most important primary producer in the lake ecosystem, the floating algae can be used as energy and food source once the POPs are adsorbed, thus leading to the biological enrichment and the biological amplification effect of the POPs, thereby causing serious harm to the aquatic organism. As a result, the planktonic algae is the end point of the eutrophication process, and it is the starting point for the transfer of the food chain, so it can be regarded as a node and a link to establish the relationship between the eutrophication and the POPs pollution. This paper is based on the dominant algae species (Microcystis aeruginosa), Scenedesmus obliqueus and Cryptomonas sp. in the rich nutrition state of the lake in China.) The two-way action mechanism of the pollution of the planktonic algae and the POPs in the eutrophic lake is clarified by the indoor simulation experiment as the carrier, and the two-way action mechanism of the pollution of the planktonic algae and the POPs is clarified through the indoor simulation experiment, and the realization of the POPs environment process in the eutrophic lake is enriched, and provides a theoretical basis for the pollution control of the lake POPs. The main results of this study were as follows: (1) The effects of phenanthrene and sulfur-sulfur on the growth of microcystis aeruginosa, aslant and cryptoalgae were studied. The results showed that the different concentrations of pollutants had the effect of stimulating the growth of the microalga, and the effect of inhibiting the growth, which was influenced by the difference of the species of the pollutants and the species of the micro-algae, and also related to the time of action and the concentration of the action. The low concentration of phenanthrene and sulfur-sulfur can promote the growth of the planktonic algae, and the high concentration is inhibited. The effect of phenanthrene on the growth of planktonic algae is higher than that of a-sultan, and the promoting effect of the two pollutants is weaker than that of a single compound. (2) The physiological mechanism of the planktonic algae was found to change with the external stimuli of a-sultan. When the algae growth environment is threatened or changed, the maximum and actual photoenergy conversion rate (Fv/ Fm and yield) in the algae can also change and reflect the rapid: the low-concentration of the field of field and a-sulfur can increase the maximum and practical light energy conversion rate of the microalga, and the photosynthesis capacity of the algae is enhanced, the high concentration is the opposite. The light energy conversion rate of the oblique-green algae is the largest, followed by cryptococcus, and the microcystis aeruginosa is relatively minimal. The improvement of the photosynthesis of the algae is better than that of sulfur-sulfur. The growth of planktonic algae is related to the change of photosynthesis, and the growth and propagation of the algae cells are affected by increasing the photosynthetic capacity of the planktonic algae and the physiological mechanism of the algae. and (3) the difference of the species of the planktonic microalga on the difference of the species of the floating micro-algae on the adsorption and the degradation ability of the target pollutant phenanthrene and the arsenic[-sultan]. The results showed that the floating algae had a strong adsorption and absorption effect and a certain degradation ability to both the phenanthrene and a-sultan in the water. Among them, the microcystis aeruginosa and the oblique-grid algae exhibit a faster rate of extracellular absorption, while the cryptoalgae is more intensive to the absorption capacity of the pollutants in the cell at the medium-term stage, which is related to the higher lipid content in the cryptoalgae cells. in that aspect of the degradation of the pollutant, the oblique generation grid algae exhibit the strongest degradation capability at the same time, but the degradation ability of the compound pollutant is lower than the degradation of the single compound; and the cryptoalgae can better degrade the compound pollutant, and the degradation rate of the phenanthrene and the low-concentration phenanthrene is better than that of the microcystin, and the condition of the high-concentration phenanthrene is just the opposite. In general, the degradation ability of the algae to the pollutant gradually increases with the time of culture, the more the algae biomass and the higher the number of the late-dead algae, the more beneficial to the degradation of the planktonic algae on the contaminants.
【学位授予单位】：南京师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X524;X173
【参考文献】
相关期刊论文 前1条
1 王亚椺;蔡亚岐;江桂斌;;斯德哥尔摩公约新增持久性有机污染物的一些研究进展[J];中国科学:化学;2010年02期
，本文编号：2380012
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