Nouveaux indicateurs d'efficience de l'azote à l'échelle de l'exploitation

The excessive use of nitrogen (N) has significant negative impacts on the environment and human health. Increasing N use efficiency and reducing N surplus balances are agricultural priorities. Here, we have developed new indicators that can be used to help manage N levels in production systems. These indicators represent an improvement over those currently in use.
We describe a new nitrogen use efficiency indicator and a new N balance indicator; both account for the impact of N inputs and variation in soil organic matter. Our third indicator makes it possible to compare a farm’s current nitrogen use efficiency with its potential nitrogen use efficiency.
We calculated values for these three indicators for 38 dairy farms in Brittany to assess the farms’ nitrogen performance. We found that our indicators yield useful results, especially when evaluating conditions on mixed crop-livestock farms.
Farmers, agricultural advisors, and researchers can use a free online tool (https://www.nefficiencycalculator.fr/en/) to calculate indicator values, which can help them identify strategies for improving their agricultural systems.