CONTEXT: Policy issues in most nations include adapting primary agricultural production to reduce greenhouse gas (GHG) emissions. Commitments have been established through multi-lateral agreements targeting GHG emission reductions to abate climate change impacts. In response to policy initiatives targeted at industries such as agriculture, producers are adopting innovative production methods and technologies to provide environmental services and mitigate emissions. GHG emissions arising from livestock production contribute to a damaging narrative surrounding agriculture, particularly beef production. OBJECTIVE: The purpose of this study is three-fold, quantifying (a) net emissions,2 (b) changes in practice, and (c) economic outcomes attributed to the forage production facet of cow-calf production. METHODS: The Saskatchewan Forage Production Survey was developed to gather forage management practices data, placing emphasis on land use and land management changes. Canada's whole-farm assessment model, Holos, was applied as a carbon accounting framework to derive the net emissions of the forage production cycle. RESULTS AND CONCLUSIONS: Results indicate carbon sequestration increased between the periods of 1991-94 and 2016-19. Gross emissions decreased to a larger degree and net emission results for the forage production facet of the Saskatchewan cow calf sector are -0.123 Mg CO2e/ha/yr in 2016-19. SIGNIFICANCE: Recommendations include the renewal of forage rejuvenation funding programs that may improve forage yields and carbon sequestration potential. Further, the expansion of term conservation easement programs to include non-native forage lands is recommended to incentivize the retention of forage land.

Cropping systems depend on external nitrogen (N) to produce food. However, we lack metrics to account for society's fertilizer dependency, although excessive increases in N application damage human and environmental health. The objective of this study is to propose a novel indicator, N fertilizer dependency, calculated as the ratio between human-controllable external inputs and total N inputs. Nitrogen fertilizer dependency has a solid mathematical base being derived from closing the nitrogen use efficiency (NUE) equation. This study also tests the value of the N fertilizer dependency concept at the cropping system (plant-soil) scale and at different spatial scales, from field to country, as a complementary indicator to promote sustainable production. The field experiments conducted with grain cereals as a main crop showed that when replacing the barley precedent crop with a legume, N fertilizer dependency accounted for soil legacy and was reduced by 15% in fertilized treatments. In a farm population, N fertilizer dependency ranged from 47 to 95% and accounted for the relevance of biological fixation and irrigation water N inputs, adding pertinent information to performance indicators (i.e., NUE). At the country scale, N fertilizer dependency showed different temporal patterns, depending mainly on the relevance of biological atmospheric N fixation. Nitrogen fertilizer dependency of global cropping systems has risen to approximate to 83% in the last five decades, even though the N exchange among regions has increased. Nitrogen fertilizer dependency has great potential to monitor the achievements of efforts aiming to boost system autonomy, and within similar agricultural systems, it can be used to identify practices that lead to a reduction of fertilizer needs. In summary, N fertilizer dependency is a new indicator to evaluate the agroenvironmental sustainability of cropping systems across the scales and provides a complementary dimension to the traditional indicators such as NUE, N output, and N surplus.