The Effects of Paleolatitude and Precipitation Gradients on Triassic Palynofloral Diversity

福厄尔9418464极端气候被认为是晚三叠世生物高灭绝率的原因，但全球变暖和气候变化对这些化石群多样性的影响尚未得到详细研究。对三叠纪纽瓦克超群连续岩心和相关露头的孢粉植物资料进行了分析，以区分古纬度、降水梯度和演化变化对孢粉植物成分的影响。纽瓦克盆地岩芯的磁性反转地层学和旋回地层学为纽瓦克超群提供了严格的时间和地理控制框架，并允许在不同但构造相似的盆地之间进行高分辨率对比。为了重建从赤道湿润带到亚赤道干旱带的晚三叠世孢粉植物多样性梯度，计划收集和比较纽瓦克和泰勒斯维尔盆地核心的四个时间片以及库尔佩尔和芬迪盆地的露头的同时代孢粉植物群。这些组合的物种计数将被用来描述三叠纪植物群落，而相似性系数和极地排序将被用来确定这些群落如何随着时间和古纬度的变化而变化。隔离植物区系组成和多样性的气候/地理和时间方面，将能够评估各种气候驱动的灭绝情景，并提供对三叠纪气候模型的有用测试。

Fowell 9418464 Climatic extremes have been suggested as the cause of high extinction rates among Late Triassic organisms, but the impact of warm global temperatures and climate change on the diversity of these fossil groups has not been examined in detail. Analysis of palynofloral data from continuous cores and correlative outcrops of the Triassic Newark Supergroup is proposed in order to separate the effects of paleolatitude, precipitation gradients, and evolutionary changes on palynofloral composition. The magnetic reversal stratigraphy and cyclostratigraphy of Newark basin cores provides a framework of rigorous temporal and geographic control for the Newark Supergroup and permits high-resolution correlation between separate but tectonically similar basins. Collection and comparison of coeval palynofloras from four time slices in cores of the Newark and Taylorsville basins and outcrops of the Culpeper and Fundy basins is planned in order to reconstruct Late Triassic palynofloral diversity gradients across 7o of paleoaltitude from an equatorial humid belt to a sub-equatorial arid zone. Species counts from these assemblages will be used to delineate Triassic vegetational communities, while similarity coefficients and polar ordination will be employed to determine how these communities changed over time and paleolatitude. Isolation of the climatic/geographic and temporal aspects of floral composition and diversity will permit evaluation of the various climate-driven extinction scenarios and provide a useful test of Triassic climate models.