湖相介形虫古生态学在环境变化研究中的应用

湖泊的水文状况和水化学条件 ,特别是盐度、离子组成、温度及深度等不仅对介形虫种属的分类、组合、丰度及分异度 ,而且对介形虫壳体的大小、形态、结构、壳饰及厚度也起着重要的控制作用。湖相介形虫的古生态学 ,可以提供重要的环境变化信息 ,近年来在环境变化研究中得到越来越广泛的应用。为了满足高分辨率环境变化 ,特别是定量研究的要求 ,必须了解介形虫的种属分类知识 ,掌握盐度和离子组成对介形虫种属变化的影响 ;必须了解介形虫种属的生命历史和生态消长的过程 ,积累介形虫种属的生态资料 ;通过定期收集野外介壳和水样分别进行种属鉴定和化学分析 ,了解湖水的盐度和温度对介壳生态特征的影响。

Application of Lacustrine Ostracodes to the Study of Environmental Changes

Paleoecological characteristics of fossil ostracod shells buried in the lake sediment sequences are increasingly studied and used to indicate the past environmental changes.The hydrological state and water chemistry of a lake,particularly the salinity,ionic composition,water temperature and depth,exert important controls not only on the taxonomy,assemblage,abundance and diversity of ostracod species,but also on the size,morphology,ornamentation,structure and thickness of ostracod shells.Changes in paleohydrological and paleolimnolgical conditions of a lake may be reconstructed based on the paleoecological information of the ostracod shells.Specialists in this field have been focusing their attention on (1)the taxonomy and controls of the salinity and ionic composition of a lake on the changes of ostracod species,(2)the life history and ecological procedure of the ostracod species concerned,to accumulate the ecological data of ostracod species(3)identifying field regular collections of ostracod shells and analyzing samples of lake waters,to learn the controls of the salinity and depth on the ecological characteristics of ostracod shells.