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对早中新世的沟鞭藻植物地理作了初步研究 ,提出北半球在当时可划分为 3个沟鞭藻地理区 ,即热带区、亚热带—温带区和北方区。热带区以典型的热带、亚热带种 Polysphaeridiumzoharyi丰富并存在偏爱热带、亚热带的种 Tuberculodiniumdinium vancampoae为特征 ,亚热带—温带区以同时存在 Tuberculodiniumdinium vancampoae和温带种 Bitectatodinium tepikiense,但缺失 Polysphaeridium zoharyi为特征 ,而北方区则以缺失 Polysphaeridium zoharyi和 Tuberculo-diniumdinium vancampoae二者且组合较贫乏为特征 ,亚热带—温带区的北界大致位于现今 68°N一线 ,此界线可随气温升高而北推 ,例如最温暖的早中新世晚期 ( 1 7～ 1 4 .5Ma)此界线可达 70°N。该带南界大致位于现今 4 5°N处 ,随着气候的转暖可能会变得模糊不清。北方区的海水此时凉而不结冰 ,即此时北极不存在冰盖。本文研究证实了前人根据大植物化石所得出的结论。
In the early Miocene, the dinoflagellate plant geography was preliminarily studied. It was suggested that the Northern Hemisphere could be divided into three Dikalian algae geographical areas at that time, ie, the tropical zone, the subtropical - temperate zone and the northern zone. The tropical zone is characterized by Polysphaeridiumzoharyi, a typical tropical and subtropical species, endemic to tropical and subtropical species Tuberculodiniumdinium vancampoae. The subtropical and temperate zone is characterized by the presence of Tuberculodinium dinium vancampoae and temperate Bitectatodinium tepikiense, but the absence of Polysphaeridium zoharyi, whereas the northern zone Characterized by the poorer combination of both Polysphaeridium zoharyi and Tuberculo-diniumdinium vancampoae, the northern boundary of the subtropical-temperate zone lies roughly 68 ° N today and can be pushed north-south with increasing temperatures such as the warmest morning Late Pleistocene (17 ~ 14.5Ma) This boundary can reach 70 ° N. The southern margin of this zone, which is located roughly at 45 ° N today, may become obscured as the climate warms. The northern sea water at this time cool without ice, that is when the Arctic does not exist ice sheet. This study confirms the conclusion drawn by our predecessors based on large plant fossils.