中国湖泊蜉蝣物种多样性与种化模式研究

我国湖泊数量众多、类型多样，是重要的静水生境，蕴藏着丰富的蜉蝣物种，它们是探讨物种形成模式的极好对象。然而，作为静水生境中重要初级消费者的蜉蝣，在我国一直未有系统分类与专项研究。本项目拟对我国50个代表性湖泊及附近池塘进行较系统的蜉蝣标本采集、成稚虫对应、种类鉴定，基本掌握它们的演化特征和物种多样性；测定各水体主要理化因子与蜉蝣稚虫的生态适应类型，拟合估算出蜉蝣目不同级别分类单元的耐污值；对比古北区和东洋区蜉蝣种类组成，分析这类生境中特有物种比例、区系组成特点，了解不同湖泊之间蜉蝣群落的组成异同和演替过程；并结合系统发育关系重建，整合分析与拟合湖泊内外蜉蝣的物种形成模式与生态位选择。本项目涉及生物系统学、生态学和生物地理学等多学科内容，它的开展和实施将基本呈现我国静水水域的蜉蝣种类概况、分布规律和群落形成及演替模式，为基本了解我国蜉蝣和昆虫多样性以及开展生物水质监测打下坚实基础。

China possesses thousands lakes, reservoirs and ponds, which are typical lentic habitats and important terminals of water system. Using different features, they can be divided into many kinds. Biologically, they have rich mayfly species and diverse adaptive types. Geographically, they scatter randomly. As a result, they provide perfect materials to research speciation patterns and evolutional process. Mayflies (Insecta: Ephemeroptera) are very important primary consumers of freshwater ecosystem, having a long series of plesiomorphies of ancient insects but having less migration ability. However, the lacustrine mayfly fauna of Chinese ponds to lakes is lacking special and systematic study. .The present project proposal, first, plans to sample, collect and rear mayflies systematically in 50 typical and selected lakes and related ponds plus reservoirs of China, then to identify and classify them carefully in order to provide a serious and convincible species diversity and fauna of them. Second, during collecting, main ecological factors, like water and air temperature, dissolved oxygen, altitude and nutrition level will be measured and recorded, ecological adaptive type of mayfly species will be observed, and then tolerance values of different level taxa of Ephemeroptera will be calculated and given. Third, this proposal wants to analyze lacustrine mayfly fauna composition of China to identify Palearctic, Oriental and its own elements, further to show its uniqueness and to know the mayfly community compositions and their succession in different waterbodies with different sizes or of different water systems. Finally, based on morphological and molecular phylogeny of newly collected materials, selected taxa, which are closely related in phylogeny and from same or different lakes or ponds, will be compared and analyzed integratedly to know their niche preferring and speciation patterns. .This project contains multi-discipline researches (such as taxonomy, ecology and biogeography) and has great scientific value. It will provide fundamental lacustrine mayfly fauna of China, outline the mayfly species diversity and their geography of this country, present mayfly speciation examples and reconstruct mayfly community formation and succession pattern.