COLLABORATIVE RESEARCH: Tropical Vegetation during the Early Part of an Ice Age: An Intercontinental Comparison of Mid-Carboniferous Floras in their Geochronologic Setting

合作研究：冰河时代早期的热带植被：中石炭世植物群在其地质年代学背景下的洲际比较Robert GastaldoEAR-0207359 ABSTRACT地球历史记录了主要的气候时段，可以概括为全球温暖或寒冷。自陆地生态系统建立以来，向全球寒冷的地球过渡，在最广泛的意义上代表着冰河时代的开始，只发生过几次，例如在石炭纪和晚第三纪(在我们目前的寒冷气候阶段开始时)。在这种过渡时期，预计所有环境和所有规模的植物区系都将发生重大变化。本项目的重点是石炭纪冰期初期，直到中-石炭世界线(320 Ma)及之后的热带陆地植物群的变化。美国、波兰和捷克共和国煤盆地中含有化石植物的岩石提供了非常完整的地层学上完整的大植物群和微型植物群数据集，这些数据集是几十年来从覆盖在煤(大型植物群)和煤本身(微型植物群)上的岩石收集的。此外，在一些地段中发现了火山成因的火山灰落凝灰岩，提供了可以提供同位素年龄的矿物，从而能够控制盆地内和世界其他地区内部和之间的生物地层对比。从这些未公布的数据和支持的集合中，将建立植被变化的标准参考概况，以记录随着时间的推移分类周转率。这些数据将有助于对热带植物群落变化的地理范围和优势度-多样性程度进行量化分析。这个项目的结果可以作为研究我们当前冰河时代类似时间间隔的基线。

Collaborative Research: Tropical Vegetation during the Early Part of an Ice Age: An Intercontinental Comparison of Mid-Carboniferous Floras in their Geochronologic SettingRobert GastaldoEAR-0207359ABSTRACTEarth history records major climatic intervals that can be generalized as either globally warm or cold. Transitions to a globally cold Earth, representing the onset of an ice age in the broadest sense, has happened only a few times since the establishment of terrestrial ecosystems, for instance in the Carboniferous and Late Tertiary (at the beginning of our current cold climate phase). At such times of transition, there are expected to be significant changes in the flora in all environments and at all scales. This project focuses on the changes in tropical terrestrial floras during the initial phases of the Carboniferous ice age, up to and immediately after the Mid-Carboniferous boundary (320 Ma). Fossilplant-bearing rocks from coal basins in the United States, Poland, and the Czech Republic provide remarkably stratigraphically complete macrofloral and microfloral data sets, which have been collected for decades from rocks overlying the coals (macroflora) and the coals themselves (microflora). Additionally, volcanogenic ash-fall tuffs have been identified within some sections, providing minerals that can provide isotopic ages, permitting control of biostratigraphic correlations within and between the basins and other parts of the world. From these unpublished data and the supporting collections, astandard reference profile of vegetational changes will be established that will document the rates of taxonomic turnover through time. These data will allow for a quantitative analysis of the geographical extent and dominance-diversity magnitude of vegetational community changes in the tropics. Results from this project can serve as a baseline for the study of similar intervals in our current ice age.