Diversity, ecology and functional traits of the medullosan seed ferns, widespread crucial plants in intramontane regions of early Permian tropical Pangea (central Europe)

该项目涉及髓科，这是古生代晚期的一组特定的种子蕨类植物。我们知道这些植物主要来自北美石炭纪煤盆地的热带森林，但它们也广泛存在于二叠纪早期的季节性干燥森林中。然而，人们对这些早二叠纪形态知之甚少，也不知道它们是什么样子的，也不知道它们在二叠纪-石炭纪过渡期间对不断变化的环境条件有怎样的进化适应。在开姆尼茨化石森林中，一个大约2.91亿年前被火山灰保存下来的古老的森林栖息地，几乎完整的植物的三维保存使得详细重建了髓质纲，包括它们繁盛的栖息地。这个为期三年的项目旨在通过评估综合收集材料，重新评估这些植物的分类，以更好地了解它们的多样性。对于二叠纪分类群，我们的目标是利用系统挖掘的化石来产生整个植物的概念，从而得出关于生长形式和结构的结论。第二个目标是尽可能详细地描述髓质树的古生态学特征，包括对3d保存的根系的研究和对它们巨大的蕨类叶子的形态计量学分析。第三个项目目标是利用解剖学参数来模拟植物的生理过程。为此目的，将发展量化化石植物导水能力的新方法，并将其应用于利用计算机模拟。研究结果为古植物学获取化石森林大气环境参数和得出水碳循环结论提供了一种新的方法工具。后者在二叠纪早期特别有趣，当时全球重要的冰川作用结束了。基于它们假定的高生物量产量和蒸发速率，我们假设在这些季节性干旱的生态系统中，管状藻对碳和水循环有实质性的影响。作为项目的一部分，这些关键参数应可量化。在以收集为基础的项目中，重点是通过提供博士职位和几个学生助理职位来培养年轻科学家，以实现学术毕业。科学工作得益于代表不同专业知识的国际合作网络。对于传统和现代科学方法的执行，我们主要使用申请机构及其合作伙伴的基础设施。科学传播是另一个相关项目，我们将向公众传播专题方面的内容，并提供有关项目进展的信息。

The project deals with the Medullosaceae, a specific group of seed ferns of the late Paleozoic. We know these plants primarily from the tropical forests of the Carboniferous coal basins of North America, but they were also widespread in seasonally dry forests of the early Permian. However, little is known about these early Permian forms, what they looked like and what evolutionary adaptations to the changing environmental conditions during the Permian-Carboniferous transition they reflect. In the Chemnitz Fossil Forest, an ancient forest habitat was preserved by volcanic ash about 291 million years ago, the three-dimensional preservation of nearly complete plants allows for a detailed reconstruction of the medullosans, including the habitat in which they thrived. The three-year project aims to re-evaluate the taxonomy of these plants to better understand their diversity by assessing comprehensive collection material. Concerning the Permian taxa, we aim to use systematically excavated fossils to generate whole-plant concepts that allow conclusions about growth form and architecture. A second goal is to characterise medullosan palaeoecology in the greatest possible detail, encompassing the study of 3D-preserved root systems and morphometric analysis of their sizable fern-like fronds. A third project goal is to model plant physiological processes using anatomical parameters. For this purpose, new approaches for quantifying the water-conducting capacity of fossil plants will be developed and applied to utilise computer simulations. As a result, we provide a new methodological tool for palaeobotany to gain atmospheric environmental parameters in fossil forests and draw water and carbon cycling conclusions. The latter is particularly interesting for the early Permian when a globally significant glaciation ended. Based on their supposed high biomass production and evaporation rates, we hypothesise that the medullosans had a substantial impact on carbon and water cycles in these seasonally dry ecosystems. These key parameters shall become quantifiable as part of the project. In the collection-based project, the focus is on training young scientists by providing a PhD position and several student assistant positions to achieve academic graduation. The scientific work benefits from an international cooperation network representing different expertise. For the execution of traditional and modern scientific methods, we mainly use the infrastructure of the applicants institution and its cooperation partners. Science communication is another relevant program item in which we will communicate thematic aspects to the public and provide information on the project's progress.