【作者】 马祖友；

【导师】 张广军； 金相灿；

【作者基本信息】 西北农林科技大学 ， 环境科学， 2005， 硕士

【摘要】 随着工农业的快速发展和废弃物的大量排放,世界水体富营养化问题越来越严重,其引起的蓝藻水华给水资源的利用、生产和人畜健康带来严重威胁。目前,环境因子对蓝藻水华暴发的机理研究已成为国际水环境研究的热点和重要方向。本论文利用从太湖分离的多种典型藻类铜绿微囊藻(蓝藻)、四尾栅藻(绿藻)和谷皮菱形藻(硅藻),进行了磷浓度、光照、温度和pH 对铜绿微囊藻增殖的生长生理特征及竞争优势的影响研究,旨在通过从蓝藻形成优势的角度揭示湖泊中蓝藻暴发水华的机理,为防治蓝藻水华提供理论基础和指导原则。实验研究表明: 1.铜绿微囊藻、四尾栅藻和谷皮菱形藻在磷资源饱和时的最大增长率μmax 分别为0.806 d-1、1.378 d-1 和1.411 d-1,半饱和常数Ks分别为0.003mg/L(P)、0.012 mg/L(P)和0.008 mg/L(P),藻细胞生长的最低磷含量分别为2.21×10-11mg/cell、5.32×10-11mg/cell 和1.36×10-10mg/cell。表明铜绿微囊藻的最大增长速率低于四尾栅藻和谷皮菱形藻,但对磷吸收能力强,而且单个细胞最低需磷量比四尾栅藻和谷皮菱形藻都低,即蓝藻细胞对磷吸收能力比绿藻和硅藻强。2.铜绿微囊藻和四尾栅藻在光资源饱和时的最大增长率μmax 分别为1.531 d-1 和2.723 d-1,半饱和常数Ks分别为4.164×103Lux 和8.271×103Lux,实验还显示铜绿微囊藻在4000Lux得到最大比增长率。表明铜绿微囊藻在光照条件下的半饱和常数比四尾栅藻低,对光照的亲和性更大。即蓝藻细胞生长对光照的需求比绿藻低。3.铜绿微囊藻和四尾栅藻都能在M11 培养基中以较快的速度生长并且达到较大的增长率μmax 和最大现存量xmax。表明蓝藻和绿藻对M11 培养基有较好的适应性,可用作蓝藻和绿藻竞争的共培养基。4.在铜绿微囊藻、四尾栅藻和谷皮菱形藻受光照影响的竞争中,当光照在4000Lux以下时,铜绿微囊藻的相对优势随光强的增加变得更大;光照在8000Lux以上时,铜绿微囊藻优势消失。表明合适的低光照更有利于蓝藻形成优势。5..在温度影响实验中,谷皮菱形藻和四尾栅藻相对于铜绿微囊藻的优势在28℃时最小,在15℃、20℃和35℃时都更大。表明合适的高温有利于蓝藻在竞争中获得优势。6.在0.012、0.112、0.412 和1.612mg/L 质量浓度的模拟湖水中,四尾栅藻均形成优更多还原

【Abstract】 The problems of Lake-eutrophication are more severe than before with fast development of agriculture&industry and discharge of waste in the world, and the water-bloom brings intimidations for using of water resource、producing and health of livestock by eutrophication, Now the mechanism study of influence of environmental factors on breaking out water-bloom of blue-green algae has been a hotspot and an important direction of international water environmental study. The paper used many algae which were separated from Taihu-lake, such as Microcystis aeruginosa, Scenedesmus quadricauda and Nitzschia palea to study the growing physiological character and competition predominance at different P concentrations, pH and under different light, temperature, in order to disclose mechanism of water-bloom of blue-green algae, supply the academic base and instructional principles for prevent water-bloom of blue-green algae. The study showed: 1.The μmax of M.aeruginosa, S.quadricauda and N.palea for P were 0.806 d-1、1.378 d-1 and 1.411 d-1, Ks are 0.003mg/L(P)、0.012 mg/L(P) and 0.008 mg/L(P) respective, the minimum P for cell are 2.21×10-11mg/cell,5.32×10-11mg/cell and 1.36×10-10mg/cell.They showed cells of blue-green algae had stronger absorption ability for P than green algae and diatom. 2.The μmax of M.aeruginosa and S.quadricauda for light were 1.531 d-1 and 2.723 d-1, Ks are 4.614×103Lux and 8.271×103Lux respective. They showed the requirement of blue-green algae for light was lower than green algae. 3.M. aeruginosa and S.quadricauda could grow fast in the M11 culture medium, It showed blue-green algae and green algae all could adapt M11 medium primely to grow,M11 could use as a common culture medium. 4.In the competition of M.aeruginosa, S.quadricauda and N.palea under different light, when light was lower than 4000Lux, relative predominance of M.aeruginosa increased with increasing of light; when light was higher than 8000Lux, the dominance disappeared. They showed proper low light was beneficial to gain predominance for blue-green algae. 5.In the experiment of temperature, relative M. aeruginosa, the competitive predominance of S.quadricauda and N.palea was least at 28℃, was larger at 15℃, 20℃and 35℃.It showed proper high temperature was help to compete for blue-green algae. 6.In the simulative lake medium of 0.012,0.112,0.412 and 1.612mg/L P concentration, S.quadricauda was dominator, and pH was large than 10.0; after adjusted pH to 5.80 with 0.04mol/L HCL, the predominance of S.quadricauda was more clear under P concentrations which were lower than 0.412mg/L, but M. aeruginosa was the dominator under 1.612mg/L P concentration. It showed pH influenced competition of blue-green algae and green algae together with P concentration 7.In the simulative lake medium, relative M.aeruginosa, predominance of S.quadricauda increased with increasing of P concentration, and the predominance was largest under 1.612mg/L; predominance succession from N.palea to M.aeruginosa was most prominent at 0.412mg/L. It showed proper P concentration was in favor of winning the competitive predominance for blue-green algae.更多还原