The diversity of trees and associated fungi has a positive impact on soil production and quality in temperate forests

The results show that tree diversity does not necessarily increase total wood or litter production, but it significantly alters the way litter is distributed over time and space. In more diverse forests, leaf fall is more spread out over time and more unevenly distributed on the forest floor.

This creates a greater variety of resources for soil organisms, which can promote their activity and improve the overall functioning of the ecosystem, such as decomposition, nutrient recycling and carbon storage in the soil.

The type of mycorrhizae (fungi) also influences certain aspects, notably timber production and the nutrient content – such as phosphorus – in dead leaves. However, contrary to expectations, combining several types of mycorrhizae does not make the ecosystem more productive.

In summary, this study shows that tree diversity plays an important role, particularly in the way in which resources recycled from fallen leaves are distributed across time and space, rather than in the total quantity produced. This diversity can therefore support greater activity amongst soil organisms and enhance forest functioning.