Ciencia del Suelo (Jun 2023)
CROP DIVERSITY IMPROVES CARBON, NITROGEN AND SOIL BIOLOGICAL FUNCTIONS IN AN AGROECOLOGICAL SYSTEM
Abstract
ABSTRACT Agroecological management is emerging as a promising alternative to current agricultural management, which is associated with deterioration of environmental quality and soil fertility. Therefore, the aim of this study was to evaluate the conversion from conventional to agroecological management by analysing soil chemical and microbiological properties. This study was carried out in the Barrow Experimental Farm of the National Institute of Agricultural Technology (INTA), Buenos Aires, Argentina, where two treatments were evaluated: agroecological (AE) and conventional (CV) management. Samples were taken at 0 - 10 cm depth, and several soil chemical and microbiological parameters were determined. The AE management resulted in an apparent restoration of soil fertility, with increases in soil organic carbon (SOC), total nitrogen (TN) and pH of 21%, 16% and 3%, respectively. AE management also led to an increase in the activities of enzymes involved in the carbon cycle: cellobiohydrolase (CBH) and β-glucosidase (BG), nitrogen cycle: N-acetyl-b-glu-cosamine (NAG) and sulfur cycle: arylsulfatase (SUL), as well as an increase in the microbial biomass car-bon and in the diversity and richness of the bacterial community (p<0.05). Bacterial and fungal communities differed between treatments (PERMANOVA, bacteria p<0.017 r2=0.1074; fungi p<0.001, r2=0.1973). The bacterial and fungal communities of the AE management were the only ones that correlated positively and significantly with the measured properties, confirming their key role in this system. The bacterial community correlated with the parameters SOC, TN, BG and SUL, while the fungal community correlated with SOC and BG. These results confirm the importance of improving above and belowground biodiversity to maintain or restore soil fertility.
