Effect of Ozone Depletion on Antarctic Marine Phytoplankton

近年来，在南极地区的早春(9月至10月)观察到的大气臭氧水平下降的同时，入射紫外线辐射(UVR)水平上升。UVR可能会对浮游植物造成极大的破坏，浮游植物是构成水生生态系统食物链基础的微型植物。该项目是对紫外线辐射对南极海洋浮游植物影响的定量评估。将通过在南极洲帕尔默站进行的为期一个月的孵化实验来评估长期暴露在紫外线辐射下的影响，该实验将使用流通室和天然表层海水。浮游植物将暴露在五种不同的UVR制度下：突发事件、两个降低水平和两个增强水平。生物量、初级生产力和色素组成的变化将每隔15天进行一次监测。在为期一个月的孵化过程中，自然样本还将在短时间间隔(2、4和8小时)内接受各种紫外线照射处理，以评估急性紫外线照射对浮游植物生产力和色素组成的影响。这种综合实验将解决紫外线辐射水平增加对南极浮游植物和整个南极海洋生态系统造成的潜在生态后果。

In recent years, reduced levels of atmospheric ozone observed in the early austral spring (September - October) over the South Polar region have been accompanied by increased levels of incident ultraviolet radiation (UVR). UVR is potentially very damaging to phytoplankton, the microscopic plants which constitute the base of the food web in aquatic ecosystems. This project is a quantitative assessment of the effects of UVR on Antarctic marine phytoplankton. The impact of chronic exposure to UVR will be evaluated via a month-long incubation experiment to be conducted at Palmer Station, Antarctica using flow-through chambers and natural surface seawater. Phytoplankton will be exposed to five different UVR regimes: incident, two reduced levels and two enhanced levels. Changes in biomass, primary productivity and pigment composition will be monitored at 15-day intervals. Concurrent with the month-long incubation, natural samples will also be exposed to the various UVR treatments over short time intervals (2, 4 and 8 hours) to evaluate the effects of acute UVR exposure on phytoplankton productivity and pigment composition. Such a combination of experiments will address the potential ecological consequences of increasing levels of UVR on Antarctic phytoplankton in particular and on the Antarctic marine ecosystem in general.