LA ACTIVIDAD BIOLOGICA DEL SUELO RESPONDE A LOS SISTEMAS DE LABRANZA EN AMBIENTES SEMIARIDOS.

Soil is the main biological reservoir on the planet, since it is transformed into living organisms, from plants to microbial communities. Different management practices and uses of the soil modify its properties, affecting the structure of the microbial communities. This work aimed to compare the biological activity of soils under conventional tillage (LC) and no-tillage (SD) after sowing (spring) and harvest (autumn) of corn (Zea mays L) in Tornquist, Argentina. Soil samples were taken at two depths, 0-5 and 5-10 cm, and various chemical (total organic carbon, extractable phosphorus, microbial biomass carbon), physical (aggregates), and biochemical/biological parameters (soil enzyme activities and community physiological profile) were determined. Our results show that SD increases soil macroaggregates and enzymatic activities while LC increases microbial biomass and soil respiration. Furthermore, microbial biomass positively correlated with micro aggregates, while enzymatic activity correlated positively with macro aggregates. Our results confirm the need to continue studying tillage systems to better understand the functioning of soil biological activity. [ABSTRACT FROM AUTHOR]