Centre for Climate Change Studies, Sathyabama Institute of Science and Technology, Rajiv Gandhi Salai, Chennai, Tamil Nadu, India.
Centre for Climate Change Studies, Sathyabama Institute of Science and Technology, Rajiv Gandhi Salai, Chennai, Tamil Nadu, India; Sathyabama Marine Research Station, Sallimalai Street, Rameswaram, Tamil Nadu, India.
Sci Total Environ. 2022 Feb 1;806(Pt 1):150445. doi: 10.1016/j.scitotenv.2021.150445. Epub 2021 Sep 21.
The sequestration of elevated atmospheric CO levels in seawater results in increasing acidification of oceans and it is unclear what the consequences of this will be on seaweed ecophysiology and ecological services they provide in the coastal ecosystem. In the present study, we examined the physiological and biochemical response of intertidal green seaweed Ulva compressa to elevated pCO induced acidification. The green seaweed was exposed to control (pH 8.1) and acidified (pH 7.7) conditions for 2 weeks following which net primary productivity, pigment content, oxidative status and antioxidant enzymes, primary and secondary metabolites, and mineral content were assessed. We observed an increase in primary productivity of the acidified samples, which was associated with increased levels of photosynthetic pigments. Consequently, primary metabolites levels were increased in the thalli grown under lowered pH conditions. There was also richness in various minerals and polyunsaturated fatty acids, indicating that the low pH elevated the nutritional quality of U. compressa. We found that low pH reduced malondialdehyde (MDA) content, suggesting reduced oxidative stress. Consistently we found reduced total antioxidant capacity and a general reduction in the majority of enzymatic and non-enzymatic antioxidants in the thalli grown under acidified conditions. Our results indicate that U. compressa will benefit from seawater acidification by improving productivity. Biochemical changes will affect its nutritional qualities, which may impact the food chain/food web under future acidified ocean conditions.
大气中 CO2 水平的隔离会导致海水酸化，目前尚不清楚这将对海藻生理生态和它们在沿海生态系统中提供的生态服务产生什么影响。在本研究中，我们研究了潮间带绿藻 U. compressa 对升高的 pCO2 诱导酸化的生理生化反应。将绿藻暴露于对照（pH 8.1）和酸化（pH 7.7）条件下 2 周，然后评估净初级生产力、色素含量、氧化状态和抗氧化酶、初级和次级代谢物以及矿物质含量。我们观察到酸化样品的初级生产力增加，这与光合色素水平的增加有关。因此，在降低 pH 条件下生长的藻体中初级代谢物水平增加。各种矿物质和多不饱和脂肪酸的含量也很丰富，表明低 pH 提高了 U. compressa 的营养价值。我们发现低 pH 降低了丙二醛（MDA）含量，表明氧化应激减少。一致地，我们发现总抗氧化能力降低，并且在酸化条件下生长的藻体中的大多数酶和非酶抗氧化剂普遍减少。我们的研究结果表明，U. compressa 将通过提高生产力而受益于海水酸化。生化变化将影响其营养价值，这可能会影响未来酸化海洋条件下的食物链/食物网。
