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：中石炭纪植物群在年代学背景下的洲际比较地球历史记录了主要的气候间隔，可以概括为全球温暖或寒冷。 地球向全球寒冷的转变，代表着最广泛意义上的冰河时代的开始，自陆地生态系统建立以来只发生过几次，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）。 在这样的过渡时期，预计所有环境和所有尺度的植物群都将发生重大变化。 该项目的重点是在石炭纪冰期的初始阶段，直到中石炭纪边界（320 Ma）和紧接其后的热带陆地植物群的变化。 在美国，波兰和捷克共和国的煤盆地的含化石植物的岩石提供了显着的地层完整的macroflora和microflora数据集，这已经收集了几十年的岩石覆盖的煤（macroflora）和煤本身（microflora）。 此外，在某些地段还发现了火山灰凝灰岩，提供了可以提供同位素年龄的矿物，从而可以控制盆地内和盆地与世界其他地区之间的生物地层对比。 从这些未发表的数据和支持性的收集资料中，将建立一个标准的植被变化参考概况，记录随着时间的推移分类周转率。 这些数据将允许在热带地区的植被群落变化的地理范围和优势多样性程度的定量分析。 这个项目的结果可以作为我们目前冰河时代类似间隔研究的基线。

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 From these unpublished data and the supporting collections, astandard reference profile of vegetational changes will be established that will document the rates of taxonomic turnover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.