Incorporating plant diversity into biogeochemical models to better infer ecosystem services
Résumé
Multi-species grasslands are a reservoir of biodiversity and provide multiple ecosystem services, including fodder production and carbon sequestration. The provision of these services depends on the control exerted on plant diversity by the interplay of biotic and abiotic factors (e.g. grazing or mowing intensity). Biogeochemistry models incorporate a mechanistic view of the functioning of grasslands and provide a sound basis for studying the underlying processes. Although major advancements in modelling have been made recently, the simulation of biogeochemical cycles mostly remains disjointed from plant species dynamics, with considerable uncertainty in the quality of predictions. In contrast, ecological models account for plant diversity with approaches adopted from biological demography, without sufficiently linking the dynamics of plant species to the biogeochemical processes occurring at the community level (which is essential to assess resilience against, for instance, drought or nutrient limitation). The MODIPRAS project explored and highlighted the role of plant diversity in the regulation of ecosystem functions. An extensive literature and model survey were carried out with an emphasis on technically advanced models reconciling biogeochemistry and biodiversity, and models readily applicable to managed grasslands in Europe. The survey sets out state-of-the-art of biogeochemical and ecological modelling.