摘要: |
于1991年1月-1991年12月,以不同浓度的硝态氮(20,60,200,600 μmol/L)研究对赤潮生物海洋原甲藻的生长和生化组成的影响,及其营养生理特性。结果表明,在氮浓度为200和600 μmol/L L时,表观光合作用强,细胞生长快,指数生长期长,叶绿素含量高,提示了由原甲藻爆发引起的赤潮与海洋富营养化有直接关系。结果还表明,海洋原甲藻可以累积蛋白质和碳水化合物,当外界氮源不能满足生长需要时,细胞内储存的蛋白质可用于维持指数生长。藻细胞可以日夜吸收氮素,碳水化合物的含量在夜间有所降低,提示其可能被利用,在夜间与氮进行同化。原甲藻的这些生理特性,使其在有适量氮存在的条件下易于形成赤潮,造成危害。 |
关键词: 海洋原甲藻 赤潮 氮营养生理 硝酸氮 |
DOI: |
分类号: |
基金项目:国家自然科学基金资助重大项目,9389008号 |
附件 |
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STUDY ON NITROGEN METABOLISM OF PROROCENIRUM MICANS WITH SPECIAL REFERENCE TO THE OCCURRENCE OF RED TIDE |
Huang Xiaohang, Shi Dongmei, Zhang Jingpu, Liu Haihang, Wu Chaoyuan
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Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071
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Abstract: |
The physiological aspects of nitrogen nutrition of Prorocentrum micans were studied in the algal physiological section of the Institute of Oceanology from Jan. through Dec. 1991. Seawater was filtered, sterilized and modified by addition of KH2PO4, FeC6H5O7, vitamin B1, and B2 at 4 mg/L, 0.5 mg/L, 100 μg/L and 0.5 μg/L, respectively. The algae were cultured in modified seawater of different concentrations (20, 60, 200 and 600 μmol/L) of nitrate. Cultures were grown under irradiance of ca. 500 μE/(m2*s) and temperature of 22±1°C. During the experiment, the growth, apparent photosynthesis, nitrate absorption rate, contents of chlorophyll a, crude protein and carbohydrates were measured periodically. The results were as follows. In all nitrate-nitrogen enriched culture media (20, 60, 200 and 600 μmol/L), longer exponential growth periods, higher contents of chlorophyll a and higher apparent photosynthetic rates were found, suggesting a positive correlation of eutrophication with dinoflagellates caused red tide. P. micans absorbed more nitrate at night (16:00-18:00) and on the contrary, more carbohydrates were found in the cells at daytime. This was because more carbohydrates were metabolized with nitrogen at night. Part of the proteins so formed was stored in the cell. In the case of nitrogen starvation, the exponential growth could be maintained up to 6 days by the consumption of stored proteins. |
Key words: Prorocenzrum micans, Red tide, Nitrogen nutrition, Nitrate |