早寒武世疑源类的古生物地理学意义

根据早寒武世疑源类在全球的古地理分布，并参考古地磁和动物化石等方面的资料，进行了早寒武世疑源类的古地理分区。结果表明：早寒武世在全球范围内可分为2个疑源类古地理大区，即波罗的海－北美－亚、澳大区和地中海大区；我国西南地区早寒武区筇竹寺期，可根据疑源类分为两个生态区，即扬子区和江南区。这一研究结果为今后各区生态结构分析，提供了重要基础资料。

Early Cambrian palaeobiogeography of acritarch

Based on the geographic distribution of acritarchs,two realms,i.e. the Baltica North America Asia,Australia realm and Mediterranean realm are recognized.During the Early Cambrian period, the former lies at low to middle latitudes with higherwater temperature, which were favourable for acritarch to flourish and differentiate .This is demonstrated by the high diversity and abundance of the assemblage. Comasphaeridium is the indicative element of the realm.During the same period, the latter may lie at high latitudes with lower water temperature,as the diversity of the assemblage was low and there was no the indicative element of the former. The Early Cambrian acritarch biogeography in the southwestern region of China may be ecologically divided into Yangtze and Jiangnan Provinces,which coincides with paleozoological data.