UV Photobiology of Planktonic Development Stages of Antarctic Benthic Invertebrates

最近记录的全球平流层臭氧减少引起了人们对海洋群落中紫外线b （UVB）辐射增加的潜在生态后果的关注。即使没有臭氧损耗，穿透海洋表层水的中波辐射也对许多海洋生物构成生物危害。最广泛的臭氧破坏发生在南极大陆和南大洋，每年春天都有超过50%的臭氧损耗记录。评估紫外线效应的一个主要障碍是对单个物种的紫外线光生物学知之甚少。在南极，一些生态上更占优势的底栖无脊椎动物物种占据了潮间带和浅海下的深度，在那里已经记录了中波辐射的生物效应。这些物种中的许多都有浮游生物发育，它们的产卵季节与臭氧消耗发生的时期相吻合；因此，它们微小的胚胎和幼虫暴露在越来越高水平的中波紫外线下。目前还没有关于中波紫外线水平增加对南极底栖无脊椎动物种群可能产生的短期或长期影响的资料。本文拟对栖息在南极半岛安弗斯岛帕尔默站潮间带和潮下区的三种重要的南极无脊椎动物进行紫外光生物学研究。这些物种分别是冠贝（帽贝）、新海胆（Sterechinus neumayeri）和海星。这些物种的成虫是南极潮间带和浅层潮下底栖生物群落的优势成员，它们的胚胎和幼虫从南方的冬末到夏季在地表水中发育数月。本研究将评估环境中波紫外线对这些物种生活史早期阶段（配子、胚胎和幼虫）的影响，包括：1)检查潜在的紫外线暴露水平；2)评估差异敏感性；3)鉴定分子、染色体和形态中波紫外线引起的损伤；4)评估中波紫外线暴露后的潜在保护和恢复。由于这些物种在温带和热带纬度都有分类上的等同，这项工作将为增加我们对当地和全球范围内紫外线影响的认识提供重要的生物学参数。

9528241 Karentz Recently documented global decreases in stratospheric ozone have brought attention to the potential ecological consequences of increased ultraviolet-B (UVB) radiation in marine communities. Even without ozone depletion, UVB radiation penetrating into surface waters of the ocean represents a biological hazard to many marine organisms. The most extensive destruction of ozone has been occurring over the Antarctic continent and Southern Ocean, where over 50% depletion is recorded each spring. A major obstacle in assessing UV effects is that very little is known about the UV photobiology of individual species. In the Antarctic, some of the more ecologically dominant benthic invertebrate species occupy intertidal and shallow subtidal depths where biological effects of UVB have already been documented. Many of these species have planktonic development and their spawning season coincides with the period when ozone depletion is occurring; thus their microscopic embryos and larvae are exposed to increasingly higher levels of UVB. At present there is no information on the potential short- or long-term effects of increased UVB levels on populations of Antarctic benthic invertebrates. The research proposed here will focus on the UV photobiology of three important Antarctic invertebrate species that inhabit intertidal and subtidal areas in the region of Palmer Station, Anvers Island, Antarctic Peninsula. These species are the limpet Nacella concinna, the sea urchin Sterechinus neumayeri and the sea star Odontaster validus. The adults of these species are dominant members of Antarctic intertidal and shallow subtidal benthic communities, and their embryos and larvae develop for months in surface waters from late austral winter through summer. This study will evaluate the impact of ambient UVB on early stages (gametes, embryos and larvae) of the life histories of these species by 1) examining potential UV exposure levels, 2) assessing differential sensiti vities, 3) identifying molecular, chromosomal and morphological UVB induced damage, and 4) evaluating potential protection and recovery from UVB exposure. Since these species have taxonomic equivalents at both temperate and tropical latitudes, this work will provide important biological parameters for increasing our knowledge about UV effects on both local and global scales.