【作者】 黄莹莹；

【导师】 王艳；

【作者基本信息】 上海交通大学 ， 环境科学， 2009， 硕士

【摘要】 我国饮用水源地的富营养化问题日趋严重,灾害性水华频发,直接威胁到供水安全。针对这一严峻现实,开发能够直接在水源地域内消除有害藻类的技术亦成为关注热点。与此同时,加拿大一枝黄花(Solidago Canadensis L.)是我国一种重要的外来入侵植物,在城乡已有蔓延成灾的趋势,在研究如何有效控制其危害的同时,其利用价值也备受关注。本课题将有害藻类控制和加拿大一枝黄花资源化利用相结合,开展了加拿大一枝黄花对藻类生长抑制的相关研究。通过实验室纯培养实验和户外围隔模拟实验,探讨了该技术的可行性,并通过电镜观察和对加拿大一枝黄花抑藻有效成分分离,分析控藻抑藻机理,为该技术的应用提供理论支持。所得主要结论如下:1)通过水浸提的方式提取加拿大一枝黄花中抑藻化感物质,实验结果证明,在实验室纯培养和户外围隔模拟条件下,水浸液均对藻类生长有抑制作用。2)纯培养条件下,加拿大一枝黄花水浸液对铜绿微囊藻生长有明显抑制作用,在宏观上表现为藻细胞浓度随着培养时间增加而降低,藻细胞呈现负增长。加拿大一枝黄花根部、茎部、叶部水浸液对铜绿微囊藻的72h-EC50分别为35.55、13.86和7.73g/L,呈递减趋势,三个部位水浸液对铜绿微囊藻生长的抑制作用由大至小依次为叶>茎>根。在微观上表现为藻细胞亚显微结构明显受到破坏,细胞内片层结构解体,淀粉粒增大且内含物总量上升以及出现质壁分离现象,进而细胞壁和细胞膜破裂的同时各细胞器也溶解,最终导致细胞死亡。3)不同受试藻种对加拿大一枝黄花水浸液的敏感性不同,而不同部位水浸液对同种受试藻种的作用效果也不一样。不同部位的水浸液均对铜绿微囊藻和斜生栅藻的生长有抑制作用,对蛋白核小球藻、水华鱼腥藻和羊角月牙藻生长的影响则呈现明显的特异性。4)在户外围隔模拟条件下,加拿大一枝黄花水浸液能有效抑制围隔内水华。投加水浸液25天后,300g实验组和1500g实验组中叶绿素a浓度分别降低了81.47%和78.55%,围隔中藻类消亡的同时,并不会引起水体藻毒素大量积累。投加水浸液初期对围隔中水质影响较大,随着时间延长影响不断减弱,后期对水质存在一定改善作用,部分水质标准等级提高。5)通过有机试剂对加拿大一枝黄花茎部和叶部水浸液进行分离,并检测各组分对铜绿微囊藻的抑藻活性。乙醚提取物仍能有效抑制铜绿微囊藻的生长,并随投加浓度的增加,抑制效果增强。对乙醚提取物进一步分离得到组分F、G、I,3个组分均有有效抑制铜绿微囊藻的生长,各组分对铜绿微囊藻生长的抑制存在联合作用。更多还原

【Abstract】 In China, the situation of eutrophication in drinking water source is getting more and more serious and harmfal algal bloom happens frequently, which constitute a threat to the safety of water supply directly. To this serious problem, the developments of technology on in-situ algal control water have become a focus these years. At the same time, Solidago Canadensis L., as an important alien invasive plants in our country, trend to be spread in urban and rural areas. Besides study on how to effectively control its hazards, its value in use also causes concern. In this subject, algal control was combimed with Solidago Canadensis L. utilization, and inhibitory effects of Solidago Canadensis L. to growth of algae were studied. Through experiments in lab and outdoor enclosures, we explored the feasibility of this technology, and through electron microscopy observation and separation of effective components of Solidago Canadensis L., we analyzed the mechanism of algal control and provide theoretical support for the application of technology.The main conclusions are followed:1) Through extracting allelochemicals from Solidago Canadensis L. by water, the results showed that the extracts could also inhibit the growth of algae both in lab and outdoor enclosure.2) In pure culture conditions, growth of M. aeruginosa was inhibited by the extracts of Solidago Canadensis L.. In macro level, algal density decreased with incubation time increasing, showing a negative growth trend. 72h-EC50 of the extracts of Solidago Canadensis L. roots, stems and leaves on M. aeruginosa were approximately 35.55, 13.86 and 7.73g/L respectively, presenting a descent trend. The extracts of leaves showed the strongest inhibitory effect, and the stems and roots were followed. In micro level, ultrastructure of algal cells had obviously been damaged. It was observed that lamellar structure was destroyed, starch grain enlarged and total amount of its inclusions increased, plasmolysis emerged, and then cell wall and membrance were broken off with organelle dissolved, leading to cell death finally.3) Different algal species were affected by extracts of Solidago Canadensis L. selectively, and the inhibitory effects of extracts of different parts of Solidago Canadensis L. on the same algae were also different. Extracts of different parts of Solidago Canadensis L. all inhibited the growth of M. aeruginosa and S. obliquus, and Chlorella pyrenoidosa, and effects on the growth of C. pyrenoidosa, A. flos-aguae and S. capricornutum showed a significant specificity.4) In outdoor enclosures, extracts of Solidago Canadensis L. effectively inhibited algal bloom. Afrer adding extracts for 25 days, chlorophyll a concentrations were reduced 78.55% and 81.47% in 300g and 1500g enclosures, without microcystines accumulation. The extracts of Solidago Canadensis L. also affected the water quality in initial stage. With time moving on, the effects became weaken. In later stage, water quality was improved, and some of water quality standards advanced.5) We used organic solvent to separate the extracts of stems and leaves of Solidago Canadensis L. and tested the effects of components on M. aeruginosa. The results showed aether extracts effectively inhibited the growth of M. aeruginosa, and inhibitory effects were enhanced with concentration increasing. Isolating aether extracts further, we obtained components of F, G and I, which could also inhibited the growth of M. aeruginosa. Between components of F, G and I, there was combined action of inhibition to the growth of M. aeruginosa.更多还原