Grazing intensity for enhanced resource use efficiency in integrated crop-livestock systems: Balancing soil carbon storage and food security

Preserving natural resources while addressing global food demand is a critical responsibility of the agricultural sector. In light of this, strategically integrating domestic herbivores into crop monocultures is seen as a promising opportunity to generate additional income and improve the efficiency of food production. Our study presents long-term results from experimentation on Integrated Crop-Livestock Systems (ICLS), revealing its productive and environmental benefits. We assessed carbon and nitrogen stocks and their temporal trend over 22 years, linking them to resource use efficiency and food provision in soybean systems with winter cover crops grazed at high, moderate, and low intensities, as well as ungrazed cover crops. Our results indicate an initial increase in carbon and nitrogen stocks across all treatments, stabilizing over time without significant differences among grazing intensities. High grazing intensity reduced the efficiency of nitrogen, phosphorus, potassium and water use, as well as soybean and pasture production. In contrast, energy production increased by 32% under moderate and low grazing intensities, and protein production by 24% under moderate grazing intensity, without compromising soil carbon and nitrogen stocks. The ICLS proved to be a key strategy for increasing food production while preserving soil carbon stock, with correct pasture management being paramount for gathering these outcomes.