Determination of local nitrogen loss for exploitation of sustainable precision agriculture: Approach description

Nitrogen management is an issue in agricultural sustainability. Compared to conventional tillage, precision agriculture practices can potentially improve nitrogen cycle efficiency, with positive benefits on crops, soils and environment. The present paper discusses the result of precision agriculture on nitrogen management, taking into account a 52 ha experimental site, in a private farm in a typical Po Valley field in north-eastern Italy, monitored from 2013 to 2015. The area is cultivated with corn (Zea mays) managed with variable rate application of fertilizer. Available data were combined in order to estimate with a 10×10 m resolution the actual efficiency in Nitrogen utilization and to quantify local losses, mainly due to denitrification, volatilization or leaching. Results show how an average loss of 76 kg.ha-1 per year was found in the experimental site, and only 11.5 % of the total area undergoing losses higher than 200 kg.ha-1. Clearly the identification of critical areas can help definition of correction actions to be implemented to reduce and minimize the impact on agriculture on environment.