Ultraviolet Radiation Induced Changes in the Patterns of Production and Composition of Biochemical Compounds in Antarctic Phytoplankton

紫外线辐射引起南极浮游植物生化化合物生产模式和组成的变化

• 批准号: 0126150
• 负责人: JOAQUIM GOES
• 金额: $ 26.34万
• 依托单位: Bigelow Laboratory for Ocean Sciences
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2006-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0126150&HistoricalAwards=false
• 关键词: Ultraviolet; Radiation; Induced; Changes; Patterns

Goes0126150There is sufficient evidence to show that present levels of incident ultraviolet radiation (UVR, 280-400nm) are impairing phytoplankton productivity in the Southern Ocean. Yet, efforts at extrapolating these findings to allow accurate and unambiguous predictions of the consequences of UVR on the Antarctic marine food web and biogeochemical cycles in the sea have been confounded with uncertainty. Estimated impacts to the Antarctic marine ecosystem range from insignificant to catastrophic. This disparity has been attributed to lack of information in key areas of UVR photobiology and photochemistry. Generally, studies have been based on broadband UVR, and do not take into account competing responses of phytoplankton at different wavelengths across the UVR waveband. Such information is critical if we are to understand the consequences of UVR enhancement on carbon assimilation by marine phytoplankton and its consequences for the food web and biogeochemical cycles. This is especially true in regions like the Antarctic where stratospheric ozone concentrations can decrease by about 50% each spring altering the proportion of UVB (280-320nm) and UVA (320-400nm) radiation that phytoplankton receive during their growth season. This project will systematically investigate changes in the production rates and composition of biochemical compounds within Antarctic phytoplankton cells under spectrally defined conditions. Investigations of both laboratory cultures and natural populations of Antarctic phytoplankton will be undertaken to understand 1) how phytoplankton cellular biochemical processes are impacted by the interplay between the different UVR wavelengths and visible light, 2) how UVR sensitivity varies across taxonomic groups of phytoplankton and 3) whether this difference in sensitivity is responsible for the dominance of one species over the other. The effect of UVR exposure on nutrient uptake by phytoplankton cells will also be studied. This information will help ascertain the role of UVR in the phytoplankton dynamics of the Southern Ocean.

GOOS0126150有足够的证据表明目前的入射紫外线辐射（UVR，280-400nm）是南大洋中浮游植物生产力的损害。然而，推断这些发现以允许对UVR对南极海洋食品网和海中生物地球化学周期的后果进行准确和明确的预测的努力与不确定性混淆。对南极海洋生态系统的估计影响范围从微不足道到灾难性。这种差异归因于UVR光生物学和光化学关键领域缺乏信息。通常，研究是基于宽带UVR的，并且不考虑在UVR波段各个波长下浮游植物的竞争反应。如果我们要了解海洋浮游植物及其对食物网和生物地球化学周期的后果，那么此类信息至关重要。在像南极臭氧浓度这样的区域尤其如此，每年春季可以降低约50％，从而改变了浮游植物在生长季节接受的UVB（280-320nm）和UVA（320-400Nm）辐射的比例。该项目将系统地研究南极浮游植物细胞内生化化合物在光谱界定条件下的变化。将对南极浮游植物的实验室培养和自然种群进行研究，以了解1）浮游植物细胞的生化过程如何受到不同UVR波长和可见光之间的相互作用的影响 其他。还将研究UVR暴露对浮游植物细胞养分吸收的影响。这些信息将有助于确定UVR在南大洋的浮游植物动力学中的作用。