Journal of Agronomy and Field Innovations

Background: Monoculture of cereal crops has made the decline in soil organic matter content, nutrient reserves, and microbial function among agro-ecosystems faster, thus threatening the agricultural productivity base of sustainable agriculture in the long run. As biological nitrogen fixation and residue carbon input make legume-based crop rotation one of the recommended tools of enhancing soil and agricultural sustainability.
Methods: The comparative study was aimed at studying three rotation systems based on legumes versus monoculture of cereals, in order to assess their impact on soil health indicators as well as agricultural productivity.
Methodology: The two-season randomized block experiment with replicated blocks compared soybean-maize, cowpea-maize and groundnut-maize crop rotations versus monoculture, with the measurement of soil properties, such as soil organic carbon content, nitrogen, phosphorus, potassium content, microbial biomass carbon content, basal soil respiration, bulk density, soil water holding capacity, aggregate stability and yield of cereals.
Results: Rotations of legumes have improved significantly the parameters of soil organic carbon, nutrients, microbial biomass, and soil aggregation, and resulted in lowering the soil density. The cowpea-maize combination was found to provide the most positive results concerning microbial biomass and carbon respiration, while soybean-maize system yielded the highest total production of cereals as well as a higher nitrogen content.
Conclusions: The application of legumes in crop rotation proves to be useful for enhancing a range of soil quality characteristics and can contribute positively to the overall sustainability of the agricultural approaches.