Assessment of the Effects of Ultraviolet Radiation on Phytoplankton in Antarctic Waters

紫外线辐射对南极水域浮游植物影响的评估

• 批准号: 9005562
• 负责人: Robert Bidigare
• 金额: $ 2.67万
• 依托单位: Texas A&M Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-04-01 至 1990-12-27
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9005562&HistoricalAwards=false
• 关键词: Assessment; Effects; Ultraviolet; Radiation; Phytoplankton

The Antarctic is currently experiencing a thirty to fifty percent springtime loss of its stratospheric ozone layer, resulting in a least a several-fold increase in UVB (280-320nm) radiation reaching the surface of the Southern Ocean. In spite of low solar elevation and persistent cloud cover, the magnitude of ultraviolet radiation fluence rates now experienced in polar regions roughly approaches that routinely measured in tropical latitudes. Perhaps more importantly, biologically damaging UVB radiation has increased in the Antarctic while both UVA (320- 400nm) and photosynthetically available radiation (PAR, 400- 700nm) have remained unchanged. This collaborative project will use recently developed improvements in atmospheric modeling and in-water UV and visible spectroradiometers to conduct a field study during austral spring 1990. The day-to-day variations in the magnitude and ratio of UVB:UVA:PAR irradiance incident on and penetrating the euphotic zone of marginal ice edge Antarctic waters will be qualified. The impact of this increase of UV radiation on abundance, composition and vitality of the phytoplankton community during the ice-edge spring bloom will be documented. During this time, strong vertical stratification restricts the phytoplankton to the upper water column, thus creating favorable conditions for increased UVB susceptibility. Special emphasis will be placed on defining biological restraints imposed by enhanced UVB radiation and altered UVB:UVA:PAR ratios on the balance of UVB photodamage to photorepair, photoprotective and photosynthetic mechanisms operating in the water column. The overall aim is an objective test of the hypothesis that phytoplankton in Antarctic waters are adversely unfluenced by ozone depletion.

南极目前正经历百分之三十到五十的 春季平流层臭氧层消失， UVB（280- 320 nm）辐射至少增加几倍 到达南大洋的表面。 尽管低 太阳高度和持续的云层覆盖， 极地地区现在经历的紫外线辐射注量率 区域大致接近热带地区常规测量的 纬度 也许更重要的是， 南极的辐射增加了，而UVA（320- 400 nm）和光合有效辐射（PAR，400- 700 nm）保持不变。 该合作项目将 使用最近开发的改进大气模型， 水中紫外线和可见光分光辐射计， 1990年春天，在南方学习。 每天的变化 UVB：UVA：PAR辐照度的大小和比率 穿透南极边缘冰缘的透光层 沃茨将合格。 紫外线增加的影响 辐射对海洋生物的丰度、组成和生命力的影响 冰缘春季水华期间的浮游植物群落将 记录在案。 在此期间，强烈的垂直分层 将浮游植物限制在上层水体， 为增加UVB敏感性创造有利条件。 将特别强调生物限制的定义 增强的UVB辐射和改变的UVB：UVA：PAR比率 对UVB光损伤进行光修复、光保护 以及在水柱中运作的光合作用机制。 总体目标是对假设进行客观检验， 南极沃茨的浮游植物不受 臭氧层损耗