The nitrogen economy of rice-livestock systems in Uruguay

Over many decades there has been a global trend away from mixed farming and integrated crop-livestock systems to more-intensive single commodity systems. This distorted local nutrient balances, resulting in environmental pollution as well soil depletion. Future food should include with tight budgets. For nitrogen (N), detailed understanding of processes, fluxes – including gaseous forms budgets at component level is needed design productive high N use efficiency (NUE) across the full chain. In Uruguay, unique rice-livestock system practiced for over 50 years, attaining production rice (mean grain yields > 8 Mg ha−1) an average livestock (120 kg liveweight gain ha−1 y−1). The aim this study was quantify components balance NUE system, so understand its long-term sustainability, draw conclusions other regions. Analysis country-level statistics each last 16 years shows balances +3.49, +2.20 +2.22 yr−1 rice, whole respectively. Based on values retained edible products, were 65.7, 13.2 23.1% While unchanged period, decreased due increasing fertiliser use. Further gains are possible by better integrating components. Actions increase raising pasture productivity controlling fertilisers rice. Tightly can play significant role re-shaping agriculture towards meeting security, socioeconomic sustainability targets.