Assessment of soil respiration and microbial indicators under different land-use systems in the Mantaro Valley, Peru

Yupanqui F.F.R.; Flores G.S.L.; da Cruz M.C.P. · Bragantia (2026) · DOI: 10.1590/1678-4499.20250280

Resumen

Land-use intensification alters soil carbon dynamics and edaphic microbial activity, thereby affecting soil quality and functionality in inter-Andean agroecosystems. The aim of this study was to analyze soil basal respiration, and its relationship with microbial indices under different land-use systems in soils of the Mantaro Valley, Peru. Four land-use systems were evaluated: forest, pasture, fallow, and cropland systems. Soil samples were evaluated collected at a depth of 0–20 cm, and oxidizable carbon, microbial biomass, permanganateoxidizable carbon, basal respiration, metabolic quotient, microbial quotient, and basal respiration normalized by oxidizable carbon were determined. Results showed differences among land-use systems. Forest and pasture systems exhibited higher contents of oxidizable carbon, microbial biomass, and active carbon, associated with greater biological activity and soil functional stability. The cropland system showed lower carbon and microbial biomass value, and higher metabolic quotient values, indicating reduced microbial efficiency and increased physiological stress. Basal respiration normalized evidenced greater carbon mineralization in fallow and cropland systems. Correlation analyses showed that soil respiration responded differentially according to land-use system and the functional status of soil carbon. Less disturbed systems promoted carbon conservation and microbial metabolic efficiency, suggesting greater sustainability for inter-Andean agroecosystems due to their sensitivity to changes in carbon quality, whereas the fallow system reflected recovery processes in which microbial biomass and metabolic efficiency appeared to be undergoing restructuring.

Instituciones: Universidad Nacional del Centro del Perú