Soil microbial biomass and oxy-hydroxides contribute to aggregate stability and size distribution under different land uses in the Central Andes

Context Agricultural intensification leads to land use changes with potential consequences for soil aggregate stability and size distribution, affecting nutrient water retention capacity, aeration, sequestration of organic carbon, biogeochemical cycling. Aims This study evaluated distribution under potato, fallow Eucalyptus globulus L. uses in Cambisols the eastern branch Central Andes, Bolivia. We also investigated relation between aggregates total C, extractable oxy-hydroxides, microbial biomass activity. Methods Aggregate stability, oxy-hydroxides were measured samples from eight plots each use. Key results Compared fields cultivated potato (Solanum tuberosum L.), increased megaaggregate content, C N free silt + clay fraction. Fallow did not lead significant structure. Soil was related both oxy-hydroxides. Microbial activity dithionite Fe positively megaaggregates stability. Oxalate Mn microaggregates. Conclusions The plantation is suitable structural amelioration sequestration, but its introduction areas should be carefully due effects on chemistry microbiology. Short-term fallowing contribute maintenance Implications In a context change, modifications would affect formation Alternative management practices are required maintain structure optimize sustainable fields.