Impact of land conservation status on soil functionality in degraded versus old‐growth forest in the Brazilian Atlantic Forest biome

Abstract Our aim was to assess the physical and biochemical properties of soil, the chemodiversity of dissolved soil organic matter (SOM), and the arbuscular mycorrhizal fungi (AMF) community associated with Ocotea porosa forests in the Brazilian Atlantic Forest biome. We evaluated (i) the physical and biochemical properties of soil using standard protocols, (ii) dissolved SOM chemodiversity and its optical characterization via Fourier‐transform ion cyclotron resonance mass spectrometry, and (iii) AMF community structure and root colonization through morphological characterization. The highest values for Ca 2+ , Mg 2+ , SOM, S, P, K + , Zn 2+ , geometric mean diameter, weighted average diameter, microbial C biomass, microbial respiration, total glomalin, root colonization, oxalic and malic acids, carbohydrates, lipids, proteins/amino sugars, biological index, and fluorescence index were observed in the preserved plots. We also found differences in the AMF community associated with land conservation status: (i) Acaulosporaceae and Gigasporaceae were strongly correlated with the preserved plots. (ii) Claroideoglomus claroideum , Funneliformis mosseae , and Rhizophagus intraradices were more prevalent in the degraded plots. This has the potential to (i) increase soil C sequestration, (ii) mitigate climate change, and (iii) contribute to the preservation of an endangered, century‐old tree species in the Atlantic Forest biome.