The Big Picture

The long-term aim of our research is to understand how variation in plant functional traits mechanistically governs biogeochemical cycles and other key ecosystem functions, in managed and natural ecosystems. To realize this, we evaluate the extent and drivers of leaf-, stem-, whole-plant-, and root-trait variability across (a) tree species globally and (b) the world’s most common crops. Based on an understanding of trait variability, our work then seeks to explain and predict rates of key ecosystem processes at individual plant- to global scales, including: (a) above- and belowground carbon (C) stocks and fluxes, (b) soil organic matter composition and cycling, and (c) plant- and ecosystem responses to environmental change drivers.


♣ Tree Functional Traits and Forest Ecosystem Processes

In forest ecosystems, variability in wood chemical traits—concentrations of C, N, lignin, cellulose, and secondary compounds (e.g., non-structural carbohydrates [NSC])—are likely strong determinants of biogeochemical processes. Our research therefore investigates: (1) variability in wood chemical traits among and within tree species; (2) environmental and phylogenetic drivers of these differences; and (3) linkages between wood chemical traits and biogeochemical processes.


ψ Crop Functional Traits and Agroecosystem Processes

The aggressive expansion of agricultural lands indicates that crop functional traits are increasingly vital determinants of ecological processes across multiple spatial scales. For instance, just four crop species (i.e. rice, maize, wheat, soy) now dominate ~50% of the ~1.42 billion ha of farmland worldwide. Their and other main crops’ trait variability are likely strong predictors of how ecosystem processes will shift under global change. Our research therefore: (1) evaluates the causes and patterns of trait (co-) variation within and among crop species and genotypes; and (2) explores how crops differ from “wild plants” in their functional traits; and (3) explores how crop leaf, root, and stem traits predict biogeochemical cycling in agroecosystems.


∇ Anthropogenic Changes in Plant Diversity

Changes in crop diversity across the world is regarded as one possible defining features of the “Anthropocene Epoch”. Our research seeks to: (1) explore how changes in crop taxonomic, phylogenetic, and functional diversity have unfolded globally and within countries over the past 60 years; and (2) examine if these changes have led to the homogenization of plant and crop diversity in managed terrestrial systems globally.