TERRAFORM: Trait Ecology and Biogeochemical Cycles in Deep Time

Plants respond to environmental change but also impact the Earth system by altering biogeochemical fluxes. Plants and their distribution have also changed profoundly across deep time as major evolutionary groups have evolved, prospered or declined. However, the current representation of this change in models is simplistic. For example, a simple succession of biogeochemical impacts along with evolution of major plant groups (i.e.,sporophytes, gymnosperm, and angiosperms) is assumed through eras of deep time, whereas major plant innovations are known to have evolved through appearance of novel combinations of traits that show variation within these lineages.

In the TERRAFORM project we are integrating trait ecology of extinct plants, state-of-the-art weathering experiments, and multi-scale modeling to study the terrestrial biosphere’s impact on the carbon, nutrient and hydrological cycles in deep-time. We focus on the effects of evolution of plant traits on chemical weathering and the global silicate cycle and how it varies over time, we hope to track how plants have impacted major episodes of biosphere upheaval. Pursuant to that focus, we perform palaeo-Earth weathering and decomposition experiments to understand the difference in effect of plant evolutionary groups and their traits on  biogeochemical fluxes. We apply these empirical insights to plant fossils spanning episodes of major environmental change (Pennsylvanian-Permian glacial interglacial cycles; the Triassic-Jurassic mass extinction; Cretaceous OAEs) to evaluate the impact of environmental change on extinct plants and their traits. This knowledge will improve the chemical weathering and terrestrial ecosystem parameterization and performance of biogeochemical models, to evaluate the plant feedback on other components of the earth system. Ultimately we aim to understand how plants TERRAFORMed the Earth, and how plant functional traits and function evolved over the past 300 million years.