Analysing intensification, autonomy and efficiencies of livestock production through nitrogen flows: A case study of an emblematic Amazonian territory

CONTEXT: Livestock farming is a major factor in the balance or disruption of bio-geochemical cycles, climate and biodiversity. The Brazilian Amazon is emblematic of these tensions between livestock production and environment. Extensive cattle production has spearheaded the territorial conquest of this region for more than 50 years, and is the main cause of deforestation. The intensification of animal production is presented as a success factor for long-term maintenance of low deforestation and a good level of production. Yet in reality there is no guarantee of this outcome, and very few studies focus on quantifying the effective intensification of the Amazonian livestock sector, and its impact on deforestation. OBJECTIVE: The objective of our article is to characterize and discuss the evolution of livestock farming in Paragominas (Brazil). This municipality is presented as an example of sustainable agrarian transition in the Amazon. After several decades with one of the highest rates of Amazon deforestation, Paragominas reduced its annual deforestation rate tenfold between 2005 and 2012. METRHODS: We analyse the livestock sector, using the method of territorial metabolism. The first step consisted in making an inventory of all material flows and all areas used either directly or indirectly by livestock farming. We calculate productive and environmental indicators' trends from 1990 to 2012 (intensity, production, efficiency, self-sufficiency, deforestation and N surplus). RESULTS AND CONCLUSIONS: We observe an extensive farming system with low density (between 0.47 and 0.83 LU/ha), low production (between 0.97 and 1.48 kg N/ha/year), low efficiency, but a large degree of self-sufficiency (exceeding 95%), and very low N surplus per hectare (between 14 and 16 kg N/ha/year). Ruminants account for 98% of all Livestock Units (LU) and over 95% of animal production. The selected indicators to characterize the intensity of farming systems are divergent: indicators expressed per unit area show extensification, with a decrease in animal density, inputs per ha and a stabilization of production per ha. However, production per animal unit and livestock efficiency increase across the study period. SIGNIFICANCE: The increase in animal production and efficiency was not related to the decrease in deforestation. The increased oversight of land use, along with strict policies, enabled the cessation of deforestation, but this did not result in the intensification of livestock farming for the moment. Our study shows that there is significant potential to increase livestock production and efficiency