阿拉斯加北端海岸带的现代介形类与环境  

RECENT OSTRACODA AND ENVIRONMENT IN COASTAL ZONE, THE NORTHWEST ARCTIC ALASKA

作　　者：李元芳[1] 张青松[1] 王国[1] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101

出　　处：《微体古生物学报》2001年第2期173-179,共7页Acta Micropalaeontologica Sinica

基　　金：国家自然科学基金 ( 4 99710 78)资助项目

摘　　要：本文主要对北极阿拉斯加巴罗地区海岸带中的现代介形类动物群特征及其生态环境进行了探讨 ,其中在盐度为 0 .15 7— 4.41g/l的河口和近河口段的河流沉积中发现 Elofsonia susitnensis Forester et Brouwers和 Cythero-morpha knikensis Forester et Brouwers的活体。据报道 ,这两种介形类活体过去见于 5 9°— 6 1°N、盐度为 1.112—32 .5 g/l的阿拉斯加湾及其沿岸带 ,在白令海、波弗特海未见及。作者在纬度更北、盐度更低的水域发现它们 ,这对北极介形类动物群研究以及控制介形类分布的环境参数的研究都提供了新认识。同时根据介形类分布特征 ,划分出This paper deals with the characteristics and distribution of recent Ostracoda in surface sediments in the coastal zone at Barrow, the northwest Alaskan Arctic. A total of 10 species of ostracods belonging to 6 genera from 19 samples collected from Barrow area have been identified. There are two types of ostracods, marine and non marine ostracods living in this area. The marine ostracods Cytheromorpha macchesneyi (Brady et Crosskey), Paracyprideis pseudopunctillata Swain, Heterocyprideis sorbyana (Jones), Rabilimis septentrionalis (Brady), Elofsonia susitnensis Forester and Brouwers, Cytheromorpha knikensis Forester and Brouwers and Cytheromorpha sp. are eurysaline and shallow water species, living in frigid and sub frigid climatic zones. The non marine ostracods Candona lactea Baird, Candona hyalina Brady and Robertson and Candona candida (Müller) are cold water species, mainly living in fresh water, of which Candona lactea can live in a slightly brackish water. Salinity and major ion composition of water bodies are the important environmental parameters which influence the occurrence and distribution of recent and non marine ostracods. Major dissolved ions of water bodies in Barrow area are Na + and Cl -. Based upon the distribution of recent ostracods, four assemblages in Barrow area can be distinguished: (1) Lagoon ostracod assemblage represented by Paracyprideis pseudopunctillata. (2) Estuarine ostracod assemblage by Elofsonia susitnensis. (3) Riverine ostracod assemblage nearby the estuary represented by Candona lactea and Elofsonia susitnensis , an assemblage mixed with marine and non marine ostracods. (4) Lake ostracod assemblages represented by Candona hyalina and Candona lactea. These four ostracod assemblages imply a decrease in salinity and marine influence from the sea to the inland.

关 键 词：现代介形类 海岸带 阿拉斯加北端 环境参数 生态组合 

分 类 号：Q913[天文地球—古生物学与地层学]