Collaborative Research: Comparative and Quantitative Studies of Protistan Molecular Ecology and Physiology in Coastal Antarctic Waters

光养和异养原生生物在极端冷水环境中普遍存在，它们对能量的生产和利用以及元素的循环至关重要。原生生物在南极食物网中的优势表明这些单细胞真核生物的主要生态和地球化学作用。了解这些群落的结构和多样性，以及使这些群落在海洋温度下限附近蓬勃发展的适应性，对于生物海洋学和了解我们星球上生命的活动和进化至关重要。原生生物组合的多样性传统上是使用显微镜和形态特征进行研究的。由于繁琐的性质，这种方法和固有的缺乏与大多数小原生生物的分类特征，这些方法是不够的，这些社区的生态研究。利用基因序列对自然发生的原生生物进行鉴定和定量的分子方法为这个问题提供了一个解决方案。该项目将通过对南极洲罗斯海海水和冰生境中的生物组合进行分子和生理研究，解决原生生物群落结构、种群丰度和适应极端寒冷环境的问题。研究将主要集中在具有生态重要性但目前尚无资料的食食性原生生物（原生动物）。这项工作的目的是促进对南极沿海原生生物群落生物多样性的新认识，为这些群落的生态研究提供工具，并编制关于原生生物物种在这一极端冷水环境中的基本生理过程的基准数据。

Caron0125437Phototrophic and heterotrophic protists are ubiquitous in extreme cold-water environments where they are central to the production and utilization of energy and the cycling of elements. The dominance of protists in Antarctic food webs indicates major ecological and biogeochemical roles for these unicellular eukaryotes. Understanding the structure and diversity of these communities, and the adaptations that allow these assemblages to flourish near the lower limit of temperature in the ocean, is of fundamental importance to biological oceanography and to understanding the activities and evolution of life on our planet. The diversity of protistan assemblages has traditionally been studied using microscopy and morphological characterization. Due to the tedious nature of this approach and the inherent lack of taxonomic characters associated with most small protists, these approaches are inadequate for ecological studies of these communities. Molecular methods that utilize gene sequences for the identification and quantitation of naturally occurring protists offer a solution to this problem. This project will address issues of protistan community structure, population abundance, and adaptation to life in extreme cold through molecular and physiological studies on assemblages in the seawater and ice habitats of the Ross Sea, Antarctica. Research will focus primarily on species of phagotrophic protists (protozoa) which are ecologically important but for which no information currently exists. The work is designed to contribute new understanding concerning the biodiversity of protistan assemblages of coastal Antarctica, provide tools for ecological studies of these assemblages, and produce benchmark data on the basic physiological processes of protistan species in this extreme cold-water environment.