伊春早白垩世木化石组合:松柏类多样性和古环境指示

The Early Cretaceous woods in Yichun: Evidence forconifer diversity and paleoenvironment significance

简要报道黑龙江伊春下白垩统裸子植物木化石组合,包括4科8属:柏科柏型木属Cupressinoxylon、落羽杉型木属Taxodioxylon,罗汉松科?叶枝杉型木属Phyllocladoxylon,松科雪松型木属Cedroxylon、油杉型木属Keteleerioxylon、云杉型木属Piceoxylon,红豆杉科红豆杉型木属Taxaceoxylon和异木属Xenoxylon。其中,松科木化石多样性最高,占据绝对优势。叶枝杉型木属、红豆杉型木属首次在黑龙江地区发现。当前木化石组合是东亚地区发现的类群最为丰富的白垩纪木化石组合之一,丰富了我国白垩纪裸子植物化石记录。木化石记录表明东北地区是早白垩世裸子植物多样性中心和分布中心之一。伊春木化石中非正常生长轮和创伤树脂道的出现反映了短时气候波动、自然灾害或者森林生态系统中植物与伴生生物间相互作用现象。该化石组合的进一步深入研究将为认识东亚现代裸子植物演化发展历史及其古环境、古气候背景提供重要依据。

This paper briefly reports the gymnosperm fossil wood flora from Lower Cretaceous of Yichun City,Heilongjiang Province,including 4 families and 8 genera:Cupressinoxylon,Taxodioxylon(Cupressaceae),Phyllocladoxylon(Podocarpaceae?),Cedroxylon,Keteleerioxylon,Piceoxylon(Pinaceae),Taxaceoxylon(Taxaceae),and Xenoxylon.Among them,the fossil woods of Pinaceae has the highest diversity and is absolutely dominant.Phyllocladoxylon and Taxaceoxylon were found in Heilongjiang Province for the first time.At present,the Yichun fossil wood flora is one of the Cretaceous wood flora with highest diversity found in China and even in East Asia,which enriches the fossil record of gymnosperms in the Cretaceous of China.The fossil record shows that Northeast China was one of the centers of gymnosperms diversity and distribution in East Asia during Cretaceous.The occurrence of abnormal growth rings and traumatic resin canals in Yichun fossil woods reflect the short-term climate fluctuations,natural hazard or the interaction between plants and the associated organisms in the forest ecosystem.Further study of this fossil wood flora will provide important evidence for understanding the evolution and development history of modern gymnosperms in East Asia and their paleoenvironment and paleoclimate background.