Soil biological indicators under agave cultivation and native vegetation in a semi-arid environment

Soil biological indicators are sensitive to changes in land use and provide important information on the functioning of soil organic matter (SOM), particularly in semi-arid environments where organic inputs and microbial activity are limited by climate. Microbial biomass carbon represents a dynamic and active pool of soil organic matter, while β-glucosidase activity reflects enzymatic processes involved in the decomposition of labile carbon compounds. This study evaluated microbial biomass carbon (Cmic) and β-glucosidase activity in the 0–30 cm soil layer under agave cultivation and native vegetation on five rural properties located in the municipality of Conceição do Coité, Bahia, Brazil. Overall, areas under native vegetation showed higher Cmic values ​​and β-glucosidase activity compared to agave cultivation. Statistically significant differences between land uses were observed only at Fazenda Fortaleza (F2) for both indicators (p < 0.05), highlighting the high spatial variability  of soil biological properties. In contrast, at Fazenda Jurubeba (F3), agave cultivation showed Cmic values ​​similar to or higher than those of native vegetation, indicating site-specific responses, probably associated with local soil conditions and management history. β-glucosidase activity showed a more conservative response, maintaining consistently higher values ​​under native vegetation on all farms. Overall, the results demonstrate that biological indicators of the soil respond in a context-dependent manner to changes in land use, emphasizing the role of site-specific factors in regulating soil organic matter. These findings reinforce the importance of integrated biological indicators to improve the assessment of soil functioning and support sustainable management strategies in semi-arid agroecosystems.