The Role of Ultraviolet Radiation in Structuring Freshwater Zooplankton Communities: Interactions with Predation

长期以来，关于什么过程调节社区组织的问题一直是生态学的中心主题。随着越来越多的证据表明气候和UV-B辐射等非生物因素的重要变化，我们需要更好地了解自然群落中非生物和生物变量之间的相互作用变得至关重要。虽然我们对捕食和可见光在构建湖泊中上层生物群落中的作用了解甚多，但对这些中上层生物群落中破坏性短波太阳辐射的生态学却知之甚少。本研究旨在探讨太阳辐射对浮游动物群落的影响，并进一步探讨其与捕食这一重要生物因子之间的生态相互作用。溶解有机碳（DOC）是控制湖泊和湖泊间破坏性太阳辐射沿垂直梯度衰减的主要因子。在本研究中，将测试几个关于DOC和DSR对宾夕法尼亚和阿拉斯加沿环境梯度的浮游动物群落的相互作用的假设。现场和实验室操作和观察都将用于检验这些假设。对破坏性太阳辐射的关注对水生生态系统的群落结构和功能具有重要意义。浮游动物是水生食物网的关键环节，它们的分布和丰度对水质和向更高营养水平的能量转移具有重要意义。收集到的数据还将有助于评估生物对湖泊内部和湖泊之间的破坏性太阳辐射梯度的生理和行为反应的相对重要性。

9509042 Williamson Questions about what processes regulate community organization have been a central theme in ecology for a long time. With increasing evidence for important changes in abiotic factors such as climate, and UV-B radiation, our need for a better understanding of the interactions between abiotic and biotic variables in natural communities becomes crucial. While a great deal is known about the role of predation and visible light in structuring pelagic communities in lakes, the ecology of damaging short wavelength solar radiation in these pelagic communities is poorly understood. The objective of the proposed research is to investigate the role of damaging solar radiation (DSR) in zooplankton communities, and more specifically, to examine the ecological interactions between this abiotic factor and predation, an important biotic factor. Dissolved organic carbon (DOC) is the primary factor controlling attenuation of damaging solar radiation along a vertical gradient in lakes, as well as among lakes. In this study, several hypotheses will be tested regarding the interactive effects of DOC and DSR on zooplankton communities along environmental gradients in Pennsylvania and Alaska. Both field and laboratory manipulations and observations will be used to test these hypotheses. The focus on damaging solar radiation has important implications for community structure and function in aquatic ecosystems. Zooplankton provide a key link in aquatic food webs and their distribution and abundance has important implications for both water quality and energy transfer to higher trophic levels. The data collected will also permit evaluation of the relative importance of physiological versus behavioral responses of organisms to gradients of damaging solar radiation both within and among lakes.