水动力对太湖营养盐循环及藻类生长的影响
发布时间：2018-08-09 08:19
【摘要】：在湖泊的富营养化过程中,除了人为作用会强烈的影响湖泊水环境外,气候变化、湖泊水文水动力的变化也会对湖泊的富营养化产生影响。作为典型的大型浅水湖泊,研究表明水动力对太湖的富营养化有着一定的影响,但目前水动力对太湖的影响机制仍不十分明确。本研究通过应用长序列太湖野外观测数据分析了野外条件下水动力对营养盐和藻类的影响;通过开展室内模拟不同扰动强度和不同扰动时间的实验研究,进一步探究了水动力对水-藻-沉积物体系下水体中营养盐以及对藻类竞争生长的影响,可为水动力对太湖富营养化的影响机理研究提供基础数据和理论依据。研究结果表明:(1)太湖长序列数据分析结果显示,在梅梁湾,随着R(风速比平均水深)的增加,营养盐和叶绿素a含量呈现出下降趋势。太湖在藻类暴发季节和非藻类暴发季节存在不同的主导风向并影响着营养盐和藻类在湖区的分布。研究区域存在两个临界风速,即日平均风速2.1和3.2 m·s-1,当风速位于两个临界风速之间时,其对应的营养盐和叶绿素a的含量明显高于低临界风速以下和高临界风速以上对应的营养盐及叶绿素a含量。数据分析显示,从1990年开始太湖地区的风速存在着明显的下降趋势,研究区域内风速处于两个临界风速之间的频率有所增加,有可能加剧太湖的富营养化。(2)不同扰动强度对营养盐和藻类生长竞争影响的实验模拟研究显示:与静置处理组相比,不同扰动强度组(100,200,300,400rad/min)中水体的TN和TDN含量显著升高(p0.05),主要是因为扰动会通过促进沉积物的再悬浮并向水体释放溶解态氮。扰动对水中氨氮含量无明显影响,可能与氨氮形态不稳定,易转化为其他形态有关。当扰动强度≥200rad/min后,水体TP和TDP含量显著高于100rad/min扰动组及静置处理组(p0.05)。扰动影响着沉积物或悬浮物向水体中释放磷。模拟装置中TDP含量较低,并随着时间的增长呈下降趋势,这可能主要与藻类对TDP的利用和沉积物对TDP的固着吸附有关。适当扰动条件下(100,200,3 300rad/min时)铜绿微囊藻细胞生物量比四尾栅藻显著增高(p0.05),铜绿微囊藻生长优势更强。扰动强度超过一定强度后(本实验显示扰动强度400rad/min时)将抑制藻类的生长。(3)不同扰动时间对营养盐和藻类生长竞争影响的实验模拟研究显示:当固定扰动强度(200rad/min)下,不同持续扰动时间组(1h,4h,12h)水体中的TN和TDN含量明显高于静置状态的对照组(p0.05),12h扰动组的TN含量显著高于1h扰动处理组(p0.05),但不同扰动时长下的TDN含量差异不显著。扰动时间的增加会通过增加水体中的悬浮物而增加水体中的TN含量。不同扰动时间处理组的TP和TDP含量均显著高于静置处理组(p0.05),扰动12h和4h对应的TP含量也显著高于1h扰动组(p0.05)。扰动12h的TDP含量显著高于4h和1h扰动处理组(p0.05)。扰动时间增长有利于促进沉积物再悬浮和沉积物向水体中释放磷。200rad/min扰动下,不同扰动时间对应的叶绿素a含量均明显高于静置条件下(p0.05),且铜绿微囊藻比四尾栅藻生物量更高(p0.05),扰动条件下,铜绿微囊藻比四尾栅藻更有生长优势。但不同扰动时间(1h,4h,12h)对藻类的生物量没有显著性差异。
[Abstract]:In the process of eutrophication, the changes in the lake water environment, the changes of climate and the change of hydrodynamics of Lake hydrology will also affect the eutrophication of lakes. As a typical large shallow water lake, the study shows that the hydrodynamic force has a certain influence on the eutrophication of Taihu, but the hydrodynamic force is at present at present. The impact mechanism of Taihu is still not very clear. In this study, the effects of water dynamics on nutrients and algae were analyzed by using long series Taihu field observation data. Through the experimental study of different disturbance intensity and different disturbance time in indoor simulation, the water dynamic to water algae sediment system was further explored. The effects of medium nutrients and on the competitive growth of algae could provide basic data and theoretical basis for the study of the influence mechanism of hydrodynamics on Taihu eutrophication. The results showed that: (1) Taihu long sequence data analysis showed that the content of nutrients and chlorophyll a decreased with the increase of R (wind speed than average water depth) in Meiliang Bay. Trend. In Taihu, there are different dominant wind directions in the algal outbreak season and the non algal outbreak season, and affect the distribution of nutrients and algae in the lake area. There are two critical wind speeds, the daily average wind speed is 2.1 and 3.2 m. S-1. When the wind speed is between the two critical winds, the corresponding nutrient and chlorophyll a content is obvious. Higher than the low critical wind speed below and higher critical wind speed above the corresponding nutrients and chlorophyll a content. Data analysis showed that the wind speed in Taihu region began to decline obviously from 1990, the frequency of wind speed between the two critical winds increased in the study area, and it may aggravate the eutrophication of Taihu. (2) different disturbances. The experimental simulation of the effects of dynamic strength on the growth and competition of nutrients and algae showed that compared with the static treatment group, the content of TN and TDN in the water body increased significantly (P0.05) in the different disturbance intensity group (100200300400rad/min), mainly because the disturbance would promote the resuspension of the sediment and release the dissolved nitrogen to the water body. There is no obvious effect of nitrogen content, which may be unstable with the form of ammonia nitrogen and easily converted into other forms. When the intensity of disturbance is more than 200rad/min, the content of TP and TDP in water is significantly higher than that of the 100rad/min disturbance group and the stationary treatment group (P0.05). The disturbance affects the release of phosphorus from the sediment or suspended matter to the water body. The TDP content is low in the simulation device and along with the time. The growth between the TDP and the TDP was mainly related to the use of algae and the solid adsorption of sediments to TDP. The cell biomass of Microcystis aeruginosa cells increased significantly (P0.05), and the growth of Microcystis aeruginosa was stronger under the appropriate disturbance (100200,3 300rad/min), and the growth of Microcystis aeruginosa was stronger than that of four. The growth of algae was inhibited when the disturbance intensity of 400rad/min was shown. (3) the experimental simulation of the effects of different disturbance time on the growth competition of nutrients and algae showed that the content of TN and TDN in the water of different persistent disturbance time group (1H, 4h, 12h) was obviously higher than that of the control group (P0.05) and the 12h disturbance group under the fixed disturbance intensity (200rad/min). The content of TN is significantly higher than that of 1H disturbance treatment group (P0.05), but the difference of TDN content under different disturbances is not significant. The increase of the disturbance time will increase the TN content in the water body by increasing the suspended matter in the water body. The content of TP and TDP in the treatment group with different disturbance time is significantly higher than that of the stationary treatment group (P0.05), and the TP content of the disturbance 12h and 4H is the same. The amount of 12h was significantly higher than that of the 1H disturbance group (P0.05). The TDP content of the disturbed 12h was significantly higher than that of 4H and 1H disturbance treatment group (P0.05). The growth of the disturbance time was beneficial to promote the sediment resuspension and the release of phosphorus.200rad/min from the sediment to the water body. The chlorophyll a content corresponding to the different disturbance time was obviously higher than that under the static condition (P0.05), and the copper green micro was slightly higher. The biomass of cystis alga was higher than that of four (P0.05). Under the condition of disturbance, Microcystis aeruginosa had more growth advantages than four algae, but there was no significant difference in the biomass of algae with different disturbance time (1H, 4h, 12h).
【学位授予单位】：中国环境科学研究院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X524
[Abstract]:In the process of eutrophication, the changes in the lake water environment, the changes of climate and the change of hydrodynamics of Lake hydrology will also affect the eutrophication of lakes. As a typical large shallow water lake, the study shows that the hydrodynamic force has a certain influence on the eutrophication of Taihu, but the hydrodynamic force is at present at present. The impact mechanism of Taihu is still not very clear. In this study, the effects of water dynamics on nutrients and algae were analyzed by using long series Taihu field observation data. Through the experimental study of different disturbance intensity and different disturbance time in indoor simulation, the water dynamic to water algae sediment system was further explored. The effects of medium nutrients and on the competitive growth of algae could provide basic data and theoretical basis for the study of the influence mechanism of hydrodynamics on Taihu eutrophication. The results showed that: (1) Taihu long sequence data analysis showed that the content of nutrients and chlorophyll a decreased with the increase of R (wind speed than average water depth) in Meiliang Bay. Trend. In Taihu, there are different dominant wind directions in the algal outbreak season and the non algal outbreak season, and affect the distribution of nutrients and algae in the lake area. There are two critical wind speeds, the daily average wind speed is 2.1 and 3.2 m. S-1. When the wind speed is between the two critical winds, the corresponding nutrient and chlorophyll a content is obvious. Higher than the low critical wind speed below and higher critical wind speed above the corresponding nutrients and chlorophyll a content. Data analysis showed that the wind speed in Taihu region began to decline obviously from 1990, the frequency of wind speed between the two critical winds increased in the study area, and it may aggravate the eutrophication of Taihu. (2) different disturbances. The experimental simulation of the effects of dynamic strength on the growth and competition of nutrients and algae showed that compared with the static treatment group, the content of TN and TDN in the water body increased significantly (P0.05) in the different disturbance intensity group (100200300400rad/min), mainly because the disturbance would promote the resuspension of the sediment and release the dissolved nitrogen to the water body. There is no obvious effect of nitrogen content, which may be unstable with the form of ammonia nitrogen and easily converted into other forms. When the intensity of disturbance is more than 200rad/min, the content of TP and TDP in water is significantly higher than that of the 100rad/min disturbance group and the stationary treatment group (P0.05). The disturbance affects the release of phosphorus from the sediment or suspended matter to the water body. The TDP content is low in the simulation device and along with the time. The growth between the TDP and the TDP was mainly related to the use of algae and the solid adsorption of sediments to TDP. The cell biomass of Microcystis aeruginosa cells increased significantly (P0.05), and the growth of Microcystis aeruginosa was stronger under the appropriate disturbance (100200,3 300rad/min), and the growth of Microcystis aeruginosa was stronger than that of four. The growth of algae was inhibited when the disturbance intensity of 400rad/min was shown. (3) the experimental simulation of the effects of different disturbance time on the growth competition of nutrients and algae showed that the content of TN and TDN in the water of different persistent disturbance time group (1H, 4h, 12h) was obviously higher than that of the control group (P0.05) and the 12h disturbance group under the fixed disturbance intensity (200rad/min). The content of TN is significantly higher than that of 1H disturbance treatment group (P0.05), but the difference of TDN content under different disturbances is not significant. The increase of the disturbance time will increase the TN content in the water body by increasing the suspended matter in the water body. The content of TP and TDP in the treatment group with different disturbance time is significantly higher than that of the stationary treatment group (P0.05), and the TP content of the disturbance 12h and 4H is the same. The amount of 12h was significantly higher than that of the 1H disturbance group (P0.05). The TDP content of the disturbed 12h was significantly higher than that of 4H and 1H disturbance treatment group (P0.05). The growth of the disturbance time was beneficial to promote the sediment resuspension and the release of phosphorus.200rad/min from the sediment to the water body. The chlorophyll a content corresponding to the different disturbance time was obviously higher than that under the static condition (P0.05), and the copper green micro was slightly higher. The biomass of cystis alga was higher than that of four (P0.05). Under the condition of disturbance, Microcystis aeruginosa had more growth advantages than four algae, but there was no significant difference in the biomass of algae with different disturbance time (1H, 4h, 12h).
【学位授予单位】：中国环境科学研究院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X524
【参考文献】
相关期刊论文 前10条
1 黄健;席北斗;许秋瑾;王喜喜;李卫平;何连生;刘鸿亮;;Experiment study of the effects of hydrodynamic disturbance on the interaction between the cyanobacterial growth and the nutrients[J];Journal of Hydrodynamics;2016年03期
2 王艺兵;储昭升;曾清如;刘建辉;;扰动对三种典型藻类生长的影响[J];生态科学;2015年05期
3 陈俊;李大鹏;李勇;黄勇;袁怡;李祥;;底泥扰动下藻类对不同形态磷在水体中分布的影响[J];中国环境科学;2015年09期
4 李大鹏;;反复扰动与藻类共存条件下底泥中不同形态磷含量变化规律[J];苏州科技学院学报(工程技术版);2015年02期
5 何爱政;刘德富;杨正健;阮腾腾;朱晓明;;不同扰动强度对浮游藻类群落结构演替的影响[J];环境科学与技术;2015年05期
6 陈瑞弘;李飞鹏;张海平;陈玲;赵建夫;黄子寒;;面向流量管理的水动力对淡水藻类影响的概念机制[J];湖泊科学;2015年01期
7 周伟;江成;何义亮;;物理扰动对水库中铜绿微囊藻和月牙藻生长及竞争的影响[J];净水技术;2013年05期
8 梁培瑜;王p，
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