红色赤潮藻（Akashiwo sanguinea）种群增长与孢囊形成机制研究
发布时间：2018-10-30 12:15
【摘要】：近年来，有害藻华在我国沿海频繁暴发，对近岸生态环境和人类健康构成了极大威胁。而有害藻华的频发与环境条件及富营养化密切关联，成为国内外研究者关注的焦点。红色赤潮藻（Akashiwo sanguinea）是广受关注的有害藻华原因种之一，研究者对该藻株藻华期间的水文气象、生物、化学等因子进行了大量研究，但对该藻种群增长研究较少，其藻华的生消机制仍不清楚。因此，弄清红色赤潮藻种群增长及其孢囊形成机制对于揭示该物种引发藻华的消亡及其防治具有重要意义。 本文以我国烟台四十里湾海域典型藻华肇事种红色赤潮藻为研究对象，采用一次性培养的方法，研究主要环境因子和氮营养盐形态对其种群增长的影响，并初步研究了氮营养盐胁迫对其孢囊形成的影响机制，，结果发现： （1）红色赤潮藻对温度、盐度、光照具有较宽的适应范围，其最适生长温度范围为20~25℃，盐度为20，光照强度为4000lx；但当温度低至15℃或升至30℃、盐度升至40该藻仍能缓慢增殖；温盐正交实验表明温度、盐度均在适宜的范围内才能实现红色赤潮藻较快的生长，盐度和温度单方面的提高或降低都不适合其快速增殖。 （2）红色赤潮藻可以吸收硝氮（NO3-）、铵氮（NH4+）无机氮源。实验范围内（10~200μM），该藻株生物量与NO3-浓度呈正相关关系；低浓度NH4+（10~100μM）可促进藻细胞生长，而高浓度NH4+（200μM）会抑制藻细胞的生长，分析原因是高浓度的NH4+会产生极大的毒性，杀死藻细胞，从而影响了其比生长率。相对于NH4+，红色赤潮藻更容易吸收NO3-。 （3）红色赤潮藻可以吸收多种类型的有机氮源，如尿素（urea）、蛋白胨（peptone）、游离氨基酸。以尿素为唯一氮源时（100μM），其比生长率最高（~0.31d-1）；其次为组氨酸（his）和蛋白胨(0.17~0.18d-1)。相对于赖氨酸（lys）、谷氨酸（glu）、甘氨酸（gly），以组氨酸为唯一氮源时，其比生长速率最高。 （4）在其他营养盐充足而N源胁迫的环境中，红色赤潮藻可形成孢囊来适应不良环境的胁迫。孢囊大小、形态与营养细胞不同。N胁迫条件下孢囊形成时间较早（2d），各处理组孢囊形成率约为8.77%~22.25%。硝氮（NO3-）、铵氮（NH4+）限制条件下孢囊最大密度分别为291、158cells/mL。
[Abstract]:In recent years, harmful algal blooms occur frequently along the coast of China, which pose a great threat to the coastal ecological environment and human health. The frequent occurrence of harmful algal blooms is closely related to environmental conditions and eutrophication and has become the focus of attention of researchers at home and abroad. Red tide algae (Akashiwo sanguinea) is one of the causes of harmful algal blooms. Researchers have done a lot of research on the hydrometeorological, biological and chemical factors during the algal blooming period, but little has been done on the growth of the algal population. The mechanism of algal blooms is still unclear. Therefore, it is of great significance to understand the population growth of red tide algae and its sporocyst formation mechanism in order to reveal the extinction of algal blooms caused by this species and its prevention and control. In this paper, the effect of main environmental factors and nitrogen forms on the population growth of red tide alga, a typical algal blooming species, in Yantai Bay of Yantai, was studied by means of one-off culture. The effects of nitrogen nutrient stress on the formation of spore sac were studied. The results showed that: (1) Red tide algae had a wide range of adaptation to temperature, salinity and light, the optimum growth temperature was 20 鈩
本文编号：2299988
[Abstract]:In recent years, harmful algal blooms occur frequently along the coast of China, which pose a great threat to the coastal ecological environment and human health. The frequent occurrence of harmful algal blooms is closely related to environmental conditions and eutrophication and has become the focus of attention of researchers at home and abroad. Red tide algae (Akashiwo sanguinea) is one of the causes of harmful algal blooms. Researchers have done a lot of research on the hydrometeorological, biological and chemical factors during the algal blooming period, but little has been done on the growth of the algal population. The mechanism of algal blooms is still unclear. Therefore, it is of great significance to understand the population growth of red tide algae and its sporocyst formation mechanism in order to reveal the extinction of algal blooms caused by this species and its prevention and control. In this paper, the effect of main environmental factors and nitrogen forms on the population growth of red tide alga, a typical algal blooming species, in Yantai Bay of Yantai, was studied by means of one-off culture. The effects of nitrogen nutrient stress on the formation of spore sac were studied. The results showed that: (1) Red tide algae had a wide range of adaptation to temperature, salinity and light, the optimum growth temperature was 20 鈩
本文编号：2299988
本文链接：https://www.wllwen.com/kejilunwen/haiyang/2299988.html
