Sprecher
Beschreibung
The plant fossil record is naturally biased and quantifiable leaf traits vary greatly by preservation conditions. Like all living organisms, plant chemical composition consists of a suite of bioelements, essential for survival, homeostasis and competition. Here we extend the ‘biogeochemical niche’ and ‘elementome’ hypotheses to deep-time floras on the basis that stable isotopes of many elements are demonstrably unaltered in compression fossils.
To test this, we use well-established chemical analysis methods of herbaria, and, for a broad fossil application and replicability, we use both non-destructive and high-spatial precision methods: portable X-ray Fluorescence and Laser Ablation Inductively Coupled Plasma Mass Spectrometry. While many other studies report fossil leaf chemical compositions, none use a holistic multi-elemental approach, capturing all present and detectable elements.
Our study reports the multi-elemental composition of fossil leaves from the Jameson Land Basin, East Greenland, which span the end-Triassic mass extinction (ETME). To ensure sufficient replication, we used ecologically dominant taxa of five distinct morphogenera.
Our data indicate an observable elemental shift in taxa that are continuous through time (across the ETME) and highlight distinct compositional differences between taxonomic groups. The study demonstrates a regional-scale elemental profile independent of depositional setting and distinguishable from host rock; supporting detection of a fossil leaf ‘palaeo-elementome’. Coupling fossil plant palaeo-elementomics with ETME palaeoecological shifts in the Jameson Land flora, facilitates establishment of a novel plant chemical ecology method in the field of palaeobotany.