Forest humus forms as a playground for studying aboveground-belowground relationships: Part 1, theoretical backgrounds

Within the context of soil biodiversity erosion and of soil recognition as a non-renewable resource i.e., not recoverable within a human lifespan, we mix theoretical backgrounds from community ecology and functional ecology to address links between aboveground diversity and belowground diversity and their functional consequences for soil. We develop a working hypothesis, for future research, stating that the best performance of the soil-plant interface (i.e., high organic matter recycling, low losses of biogenic elements, and plant productivity) is achieved when all communities (plant and soil biota) have reached a similar organizational pattern based on species assemblages, limiting functional traits similarity, and maximizing complementary traits. We conclude that the humus system is the best candidate for testing this hypothesis.