Integrated leaf trait analysis – a new tool for analyzing European Paleogene ecosystems

本项目将结合现代叶片功能性状分析方法和昆虫对叶片的危害，为古近系叶片组合的古生态研究建立一个新的有意义的工具。综合叶片性状分析方法可以更好地描述陆地生态系统的结构和功能，特别是那些缺乏动物化石数据的陆地生态系统。主要研究环境变化，特别是气候和植物区系变化对这些古生态系统植物经济和营养网络的影响。特别地，它处理了这些变化如何影响叶片的功能性状以及植物和昆虫食草动物之间的相互作用的问题。选取晚始新世、早渐新世和晚渐新世三个不同的地层水平和古北海沿海平原及其火山状腹地两个不同的生境，研究并量化叶片性状和叶片昆虫危害的变化和化石叶片组合。沿海平原化石组合选自德国中部莱比锡海湾，火山状生境的化石组合主要位于北波西米亚。大约13 Ma的时间间隔包括始新世-渐新世交替和晚渐新世变暖等全球重要的气候变化，同时也是植被变化的显著时期。这两种不同的生境与不同的沉积环境和沉积相类型有关。叶片性状的预期相依赖关系将在三个给定的时间间隔内进行跟踪和量化。重要的形态和形态计量性状是性状组合类型确定等定性参数和叶大小、叶面积质量、叶圆度等定量参数。通过研究德国和捷克共和国几个公共科学收藏提供的大量标本，应该保证结果的重要性。长期的古生态研究有三个连续的研究目标：(1)记录沿海平原组合和火山形腹地组合的功能叶性状和昆虫食草性特征模式；(2)认识气候相关变化对两种生境类型的功能叶性状和昆虫食草性模式的影响；(3)以中国西南地区类似现存森林为例，评价化石记录的意义。如果对叶片性状、昆虫食草性和地形学过程进行连贯的研究，预计这些研究将支持化石叶片组合仅作为基本环境指标的假设。为了实现这些目标，申请人的工作小组与经验丰富的pi及其工作小组合作。

The project will be conducted to combine modern approaches for analyzing functional leaf traits and insect damage on leaves for establishing a new meaningful tool for palaeoecological studies of Paleogene leaf assemblages. This new approach named Integrated Leaf Trait Analysis will be introduced to better characterize ecosystem structure and functioning of terrestrial ecosystems, especially those that lack data from animal fossils. Main project aim is the investigation how major environmental alterations, especially climate and floristic changes, impact on plant economics and trophic network in these palaeoecosystems. In particular it deals with the question how these changes influenced functional leaf traits and the interaction between plants and insect herbivores. To figure out and quantify shifts and changes of leaf traits and insect damage on leaves fossil leaf assemblages from three distinct stratigraphic levels, i.e. late Eocene, early Oligocene and late Oligocene, and from two distinct habitats, i.e. the coastal plains of the Palaeo-North Sea and its volcanic-shaped hinterland are selected. Coastal plain fossil assemblages are selected from the central German Leipzig Embayment and assemblages from volcanic-shaped habitats are mainly located in Northern Bohemia. The approximately 13 Ma long time interval includes globally important climate shifts such as the Eocene-Oligocene turnover and the late Oligocene warming which are simultaneously remarkably periods of vegetation change. The two distinct habitats are linked to distinct depositional settings and sedimentary facies types. Expected facies dependencies of leaf traits will be traced and quantified within the three given time intervals. Important morphological and morphometric leaf traits are qualitative parameters such as the determination of the Trait Combination Type and quantitative parameters such as leaf size, leaf mass per area and circularity. The significance of the results should be guaranteed by studying large quantities of specimens which are provided by several public scientific collections in Germany and the Czech Republic. The long-term palaeoecological study addresses three consecutive study aims: (1) recording characteristic pattern of functional leaf traits and insect herbivory for coastal plain assemblages and volcanic-shaped hinterland assemblages, (2) recognizing the impact of climate related changes on functional leaf traits and insect herbivory pattern in both habitat types, and (3) evaluation of the meaningfulness of the fossil record by a case study in a similar extant forest in SW China. It is expected that the investigations support the hypothesis that fossil leaf assemblages only serve as fundamental environmental proxy if leaf traits, insect herbivory and taphonomic processes are coherently investigated. To achieve these goals applicant’s working group collaborates with experienced PIs and their working groups.