School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
College of life Sciences, Huaibei Normal University, Huaibei, 235000, China.
Environ Sci Pollut Res Int. 2018 Sep;25(27):27493-27502. doi: 10.1007/s11356-018-2792-6. Epub 2018 Jul 25.
Physiological metabolisms of seaweeds usually suffered climate changes in the field. Gracilariopsis lemaneiformis and Ulva lactuca, collected from Nan'ao Island, Shantou, China, were cultured under ambient and elevated CO supply (390 and 800 μl L), with low and high temperatures (15 °C and 25 °C) for 2 weeks, aiming to compare the difference of the main physiological metabolism between two seaweed species in response to the elevated CO and high temperature. At 15 °C, the pH reduction in the culture medium caused by elevated CO was larger in G. lemaneiformis than in U. lactuca. At 25 °C, elevated CO significantly increased photosynthetic rates (P or P) and maintained constant respiratory rates (R) in G. lemaneiformis. However, for 25 °C-grown U. lactuca, the increment of CO did not enhance the P (P) rates but rapidly decreased the R rates itself. With the higher R/P ratios in G. lemaneiformis than U. lactuca, the warming thereby promoted more allocation of photosynthetic products to respiratory consumption in G. lemaneiformis. Both P and R rates exhibited lower temperature acclimation in two seaweeds. In addition, elevated CO markedly increased the relative growth rate (RGR) and phycobiliprotein (PB) contents at 25 °C, but exhibited no enhancement of chlorophyll a (Chl a), carotenoids (Car), soluble carbohydrate (SC), and soluble protein (SP) contents in G. lemaneiformis, with the reduction of SC when temperature increased only. We suggested that climate changes were probably a more benefit to U. lactuca than to G. lemaneiformis, inherently justifying the metabolism during G. lemaneiformis maricultivation.
海藻的生理代谢通常会受到野外气候变化的影响。从中国汕头南澳岛采集的龙须菜和浒苔，在环境和升高的 CO 供应（390 和 800 μl/L）下，以及低温（15°C）和高温（25°C）下培养了 2 周，旨在比较两种海藻在应对升高的 CO 和高温时主要生理代谢的差异。在 15°C 时，升高的 CO 导致培养基 pH 值降低，在龙须菜中比在浒苔中更大。在 25°C 时，升高的 CO 显著增加了龙须菜的光合作用速率（P 或 P），并保持了恒定的呼吸速率（R）。然而，对于在 25°C 下生长的浒苔，CO 的增加并没有提高 P（P）速率，反而迅速降低了 R 速率本身。由于龙须菜的 R/P 比值高于浒苔，因此变暖促进了更多的光合产物分配到呼吸消耗中。两种海藻的光合作用和呼吸作用都表现出较低的温度适应能力。此外，升高的 CO 在 25°C 时显著增加了相对生长速率（RGR）和藻胆蛋白（PB）含量，但没有提高叶绿素 a（Chl a）、类胡萝卜素（Car）、可溶性碳水化合物（SC）和可溶性蛋白质（SP）含量，当温度升高时仅降低了 SC 含量。我们认为，气候变化对浒苔的益处可能比对龙须菜更大，这从根本上说明了龙须菜在养殖过程中的代谢情况。
