【作者】 易齐涛；

【导师】 白洁；

【作者基本信息】 中国海洋大学 ， 环境科学， 2006， 硕士

【摘要】 随着我国现代经济的高速发展和人口剧增,工业废水、生活污水、农业用水严重影响了我国的淡水和海水资源,致使水质恶化,水功能丧失。水体污染、富营养化已成为我国最为关注的海洋环境问题之一。利用藻类进行生物修复成为研究的热点,其中菌藻关系对生物修复作用有重要影响,本文就细菌与海洋微藻的相互作用及对无机营养盐吸收的影响进行了研究。以四种抗生素为除菌药物获得了小球藻chlorella sp.、Isochrysis galbana Platymonas sp.、等鞭金藻Isochrysis galbana、和青岛大扁藻Platymonas sp.三种无菌藻,并以无菌藻对环境细菌进行选择,传代培养获得了稳定的菌藻共生体系,并研究了菌藻的相互作用及其营养盐吸收的影响。从小球藻的菌藻共培养液中分离出6株细菌,分别以无菌小球藻为对照组,研究单菌株对小球藻生长的影响,发现一株能促进小球藻的生长,其他对小球藻的生长没有明显影响;以无菌微藻为对照组,研究了混合菌株对海洋微藻生长的影响,发现在加入NH4+-N的f/2培养液中,混合细菌能促进海洋微藻的生长。藻液中pH,溶解氧和CO2的浓度的平衡是影响细菌对海洋微藻生长影响的重要环境因子。研究了藻液对细菌生长的影响,发现细菌细胞密度同藻的生理状态密切相关,在藻指数生长前期,细菌在接种两天后达到第一个高峰,藻液中可利用有机物是限制细菌生长的主要因素,在藻的指数生长期,藻的快速增值限制了细菌的生长,而从藻的稳定起开始,细菌又呈现出逐步生长趋势。以藻胞外提取液培养单菌株和混合菌株,发现混合菌株的生长和单菌株的生长趋势不同,胞外可利用有机物和无机营养盐是影响细菌生长的重要因素。以无菌微藻培养液为对照组,研究了菌藻培养液中对无机营养盐的吸收情况,表明在NH4+-N是微藻优先利用的氮源,细菌具有比海洋微藻更高的营养盐吸收效率,细菌的存在能加强微藻对NH4+-N和PO43--N的吸收;以藻胞外提取液培养混合细菌,发现NH4+-N是细菌优先利用的氮源,NH4+-N的存在能加强细菌对磷的吸收。总之,细菌受海洋微藻藻的和藻液环境的影响,在藻液中主要通过影响微更多还原

【Abstract】 With the rapid economic developments and the expanding population in our country, water resource is influenced dramatically by the sewage in industry, living,agriculture, resulting in the deterioration and decline in water quality and function. The eutrophication is becoming one of the most attractive marine problems. The bio- remediation of algae in polluted water is carried out as a hot technology. Caring the especially important relationship between bacteria and algae, the study of absorption in inorganic nutrients influenced by the relationships between marine bacteria and microalgae is carried out in this thesis.Axenic cultures of 6 species of planktonic microalgae, chlorella sp., Isochrysis galbana and Platymonas sp. are obtained by the treatment of penicillin, gentamicin, kanamycin, and streptomycin. Then the environmental bacteria is naturally selected through the mixed culture with the microalgae, to lead a symbiosis between bacteria and microalgae ,and the characteristics of symbiosis are formulated by the fingerprint of DGGE.Six strains of bacteria of mixed culture medium are isolated. Then using the axenic microalgae as a comparison, the study of the influence of microalgae growth made by single strain is carried out. Results show that one of the six strains can accelerate the growth of chlorella while others have no significantly influence. Also, the mixed bacteria of symbiosis is added into the microalge culture medium to find out the influence on the growth of microalgae, and find that in the f/2 culture medium, the growth is not influenced by mixed bacteria but is accelerated in the f/2 culture medium added with ammonium. The balance between of pH ,dissolved oxygen and concentration of CO2 are very important environmental factors during the interaction. The bacteria dynamic changes are observed during the culture, and the amount of bacteria is found changing with the physiological situation microalgae. During the更多还原