Ozone Diminution, Ultraviolet Radiation and Photoplankton Biology in Antarctic Waters

南极正在经历平流层臭氧的大量春季损失，导致紫外线B(UVB，280-320 nm)辐射增加。到达地表的紫外线辐射强度现在接近在热带纬度测得的水平。也许更重要的是，南极的UVB辐射有所增加，而UVA(320-400 nm)和光合作用有效辐射(PAR，400-700 nm)都保持不变。1990年春季期间，将在一项为期六周的实地研究中使用大气层模拟和海洋仪器技术的最新改进。主要目标将是记录在冰缘春季水华期间紫外线辐射对浮游植物群落的影响。在此期间，海洋过程为UVB敏感性的增加创造了有利条件。将使用生物和生物光学信息来定义和量化依赖臭氧的UV与PAR比率的振荡与浮游植物生产力之间的联系。将特别强调确定增强的UVB和改变的UVB：UVA：PAR比率对在南大洋运行的UVB光损伤与光修复、光保护和光合作用机制之间的平衡施加的生物限制。总体目标是验证南极水域浮游植物受到臭氧消耗不利影响的假设。

The Antarctic is now experiencing large springtime losses of stratospheric ozone, resulting in an increase in ultraviolet B (UVB, 280-320nm) radiation. The magnitude of ultraviolet radiation reaching the surface now approaches that measured in tropical latitudes. Perhaps more importantly, UVB radiation has increased in the Antarctic while both UVA (320-400nm) and photosynthetically available radiation (PAR, 400-700nm) have remained unchanged. Recent improvements in atmospheric modeling and technology in oceanographic instrumentation will be used in a six week field study during the austral spring 1990. The prime objective will be to document the impact of UV radiation on the phytoplankton community during the ice-edge spring bloom. During this time, oceanographic processes create favorable conditions for increased UVB susceptibility. Biological and bio-optical information will be used to define and quantify linkages between ozone-dependent oscillations in UV to PAR ratios and phytoplankton productivity. Special emphasis will be placed on defining biological restraints imposed by enhanced UVB and altered UVB:UVA:PAR ratios on the balance of UVB photodamage to photorepair, photoprotective and photosynthetic mechanisms operating in the Southern Ocean. The overall aim is to test the hypothesis that phytoplankton in Antarctic waters are adversely influenced by ozone depletion.