我国晚中生代单缝孢真蕨植物兴衰史及意义  

CHARACTERISTICS OF THE LATE MESOZOIC MONOLETE SPORE FERNS FROM CHINA AND THEIR PALAEOCLIMATIC AND EVOLUTIONARY SIGNIFICANCE

作　　者：邓胜徽[1] 

机构地区：[1]石油勘探开发科学研究院

出　　处：《地质论评》1995年第2期135-143,共9页Geological Review

基　　金：国家自然科学基金 (49202017)

摘　　要：从大化石和孢粉资料两方面总结了我国晚中生代单缝孢类真蕨植物的特点及其兴衰史,认为单缝孢类真蕨植物在我国北方地区早白垩世植物群中的出现、繁盛和衰退与该地区的潮湿,特别是温暖潮湿型古气候背景关系十分密切,据此阐明了该类植物的潮湿、特别是温暖潮湿型古气候的指示意义。其中多数化石与现生真蕨Athyrium,Dryopteris属等的形态和繁殖器官结构非常相似,反映真蕨类进入了一个新的演化阶段,并提出Dryopteris和Athyrium属很可能起源于我国东北地区,时间为早白垩世或略早一些的观点。The morphological characters, reproductive structures and distribution of the Late Mesozoic monolete spore ferns from China are briefly described in the paper. These ferns are considered to be important elements of the Early Cretaceous flora from Northeast China and as one of the main differences between the Early Cretaceous floras from Northeast China and South China. Information of megafossils and dispersed spores show that the Late Mesozoic monolete spore ferns are limited to regions north of about 38°N latitude, mainly in Northeast China. They apeared in Northeast China in the Late Jurassic, and then extended to North China and flourished in the middle Early Cretaceous and declined in the late Early Cretaceous. The history and distribution of these ferns were in good agreement with the paleoclimatic changes in the Early Cretaceous. These indicate that the distribution of the Late Mesozoic monolete spore ferns was controlled by the humid, especially humid - warm climate. 1 he contents of the dispersed monolete spores in the strata are inversely proportional to that of Classopollis, Schizaeoisparties and Ephedripites which reflects dry climates. Therefore, the Late Mesozoic monolete spore ferns can be used as an indicator of the humid, especially humid -warm climate in the Late Mesozoic. Data from other areas excluding China support this conclusion.Most of the monolete spore fern fossils are very similar to some extant monolete spore ferns in both outlines and reproductive structures, which suggests that the Late Mesozoic was an important evolutionary stage of ferns. Aihyrium and Dryopteris were very likely to originate in Northeast China in the Early Cretaceous or a little earlier.

关 键 词：晚中生代 单缝孢蕨类 古气候意义 古植物 

分 类 号：Q914.64[天文地球—古生物学与地层学]