Integrated crop-livestock systems: A sustainable land-use alternative for food production in the Brazilian Cerrado and Amazon

Sustainable intensification of agriculture is central to deal with the challenges of feeding a growing population while promoting a rational use of environmental and economic resources. Nowhere is this challenge more prominent than in Brazil, where low productivity and environmentally degrading agricultural activities occupy vast areas. We used the emergy synthesis approach, including innovative indices - emergy footprint and carbon-emergy output intensity - to assess and compare the environmental performance of an integrated crop-livestock system to a continuous crop and a continuous livestock system. Our analysis uses survey and empirical case study data from the 2017/18 crop season in Mato Grosso state, Brazil - the largest grain and beef producer in the country. Economic indicators such as gross revenue, production costs and profitability were calculated to complement the sustainability assessments. The emergy indices indicate that integrated crop-livestock system shows a balanced performance between input use and economic and environmental outcomes. In contrast, due to its heavy dependence on external inputs, the cropping system has poor environmental results, but the highest profitability. By excluding these environmental costs, current accounting of soy-corn production in Brazil dramatically overstates its net benefits to society and overall sustainability. The Emergy Sustainability Index for the integrated system was 0.66 and its Net Profit was USD 235.69 ha-1, while for the continuous crop system the values were 0.47 and USD 295 ha−1, respectively. The livestock system performed poorly in both, economic and environmental outcomes, underscoring the need to transition away from existing extensive systems. Livestock shows the highest positive greenhouse gas emissions, 7.98 E−09 tonCO2eq for each joule produced, and Net Loss of USD 0.58 ha-1. These results provide further support for Brazil’s investment in integrated systems as part of its climate mitigation and sustainable agricultural development plans and warrant consideration in sustainable agriculture initiatives in other countries where cattle production is widespread.