摘要
硅藻席沉积是由"树荫种"硅藻大量勃发并快速堆积而成。与成席硅藻同时大量生长的还有其他体型较小的硅藻。通过对WPD03和WPD12孔末次冰期低纬度西太平洋硅藻席沉积样品进行硅藻分析,共鉴定硅藻40属101种(含变种)。硅藻组成中既有淡水种和沿岸种以及外洋冷水种,也有外洋暖水种,但主要以大洋暖水种和广布种为主。在主要的硅藻属种中,Thalassionema frauenfeldii的平均百分含量最高,Thalassionema nitzschioides、Azpeitia nodulifera、Nitzschia marina、Hemidiscus cuneiformis等次之,这5种硅藻占了整个非成席硅藻物种相对百分含量的85%左右,说明在该海域表层水体硅藻席沉积过程中,这5种硅藻最容易与成席硅藻在同时期的环境中生存,形成勃发。初步断定硅藻席形成时期环境为热带水体的大洋性环境。
The diatom mat deposits are giant ＂shade flora＂ diatoms bloom and quickly deposit to the ocean bottom.At the same time,some other species of diatoms also bloom.A total of 101 diatom taxa（including variation） belonging to 40 genera has been identified from the 155 samples based on the two cores of WPD03 and WPD12.It was found that the relative percentage of Thalassionema frauenfeldii is the highest,and that of Thalassionema nitzschioides,Azpeitia nodulifera,Nitzschia marina,and Hemidiscus cuneiformis takes the second place.The five species take about 85% of all diatom species’ relative percentage.The result indicated the five species are the easiest to coexist and bloom with the diatoms forming mats in the diatom mats’ deposit process of the surface water in this area.We estimated that the period for forming mats was a tropical environment of open-ocean circulation.
出处
《热带海洋学报》
CAS
CSCD
北大核心
2012年第4期75-82,共8页
Journal of Tropical Oceanography
基金
国家自然科学基金项目(41006032)
国土资源部海洋油气资源和环境地质重点实验室基金项目(MRE201123)
中国科学院海洋地质与环境重点实验室开放基金项目(MGE2001KG08)
关键词
硅藻
硅藻席
西太平洋
末次冰期
diatom
diatom mat
Western Pacific
last glacial
