Agroforestry practices fail to mimic the aboveground-belowground interactions of Amazon mature forest

The anthropogenic pressure exerted by an alarming and increasing deforestation threatens tropical ecosystems. Notably, this mainly occurs in the eastern and southern Amazonia areas known “deforestation arc”, because of extensive pastures and shifting cultivation. Shifting cultivation is trapped in a vicious cycle of unsustainable intensification and degradation, with repeated slash-and-burn cycles and shortening fallow periods translating into reduced agronomic productivity and, ultimately, rural poverty. Agroforestry systems may offer a sustainable alternative, reportedly mimicking the plant-soil interactions of the forest. We investigated interactions between microbial community, environmental parameters and plants in different agroforestry systems and in secondary and mature rainforest controls in Amazonia. Management practices reduced bacterial dependence on plant biomass and soil factors (aboveground-belowground interactions), which contrasted with mature forest interactions. This reduction may compromise the sustainability of agroforestry, especially the functioning of nutrient cycling. Consequently, management strategies should focus on enhancing plant-soil interactions to recapture the mature forest interdependencies.