大兴安岭中段东坡龙江盆地早白垩世植物化石新材料

Early Cretaceous plant fossils and their paleoenvironment in Longjiang basin on the eastern slope of middle Da Hinggan Mountains

报道大兴安岭中段东坡龙江盆地早白垩世18属31种植物大化石和18属21种孢粉化石。该植物群以有节类、真蕨类、银杏类及茨康类最为丰富,其次为苏铁类、本内苏铁类及化石果类,时代可能为早白垩世早中期。根据植物特征及伴生的热河生物群生物特点,龙江盆地早白垩世总体上可能处于温暖湿润的季节性变化的暖温带,并伴有短暂的干旱、半干旱气候,古环境应为沼湖环境,并在湿地和山坡上生长着不同的生物群落。

An Early Cretaceous flora from the Longjiang basin on the eastern slope of middle Da Hinggan Mountains is reported. The flora consists at least of 31 species of 18 genera in magafossils and 17 species of 21 genera of palynofossils, and is predominated by articulatae, ferns, ginkgoales and czekanowskiales, followed by bennettitales, cycadoales and Carpolithus, which are probably early-middle Early Cretaceous in age. According to the plant characteristics and associated biological characteristics of Jehol Biota, the Longjiang basin seems to have experienced warm and humid temperate seasonal changes, accompanied by a brief arid, semi-arid climate in the early-middle Early Cretaceous in general. The paleoenvironment of Longjiang basin should be the lake marsh environment with different biomes in the wetlands and hillside.