Combined effect of intercropping and minimum tillage on soil carbon sequestration and organic matter pools in the semiarid region of Brazil

This study aimed to evaluate the effect of two intercropping systems and minimum soil tillage in the semiarid region of Brazil on soil organic carbon (SOC) and pools of soil organic matter (SOM), compared with the native vegetation (NV). The first intercropping was cultivated with beans, sesame and pigeon pea, whereas the second was cultivated with cotton, maize, beans, sesame and pigeon pea. Two areas under NV, adjacent to the crop areas, were also sampled. Soil sampling were collected from 0-5, 5-10, 10-20, 20-30 and 30-50 cm layers in three plots per area to characterise the SOM (SOC, soil nitrogen, humic substances, microbial biomass, and mineralisable carbon). Our results demonstrated that, when compared with the NV, intercropping systems conducted with minimum soil tillage were effective in maintaining and sometimes increasing the levels and stocks of SOC and some SOM fractions such as microbial C and humic substances, and therefore, these systems can be an alternative form of sustainable soil management in the semiarid region of Brazil.