Work package 3

In WP3, we elevate the experimental control of canopy disturbance and drought to gain a deeper mechanistic understanding of how forest biodiversity responds to these stressors. While large-scale surveys, like WP1 and WP2, are invaluable, they often face the challenge of environmental co-variation. To disentangle the effects of drought and canopy disturbance, WP3 employs a highly controlled, full-factorial experiment that isolates the individual and combined impact of these drivers.

At our experimental site in the Vagevuurbossen (Wingene, BE), we simulate the ‘no-analog’ light regimes currently appearing in European forests by carefully clipping tree branches and foliage within 12 circular forest plots. This approach creates distinct levels of canopy disturbance within the forest stand. To simulate drought, we have installed shelters (similar to those in WP2) that capture incoming precipitation. In total, the experiment houses 432 hydrologically isolated mesocosms containing diverse plant species and communities. By exposing these communities to these manipulated environmental conditions, we can precisely observe how biodiversity responds to these stressors.

Ultimately, the goal of WP3 is to determine why certain species thrive while others decline under the pressures of a changing climate. By achieving this high level of experimental orthogonality, we gain the mechanistic clarity needed to predict how future forest understoreys will shift as canopy disturbance and drought continue to interact.