2017/01/01 by Julie Constantin, Constantin, Julie, Nicolas Beaudoin +11
Environmental Science · #0 #Drainage #Engrais vert #Green manure #Nitrate #Soil water content #Stock d’eau du sol #Wastewater Treatment and Nitrogen Removal
paper · pdf · doi:10.15454/1.517407043672525e12
openalex publication_date 2017/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/19
Sown in the summer/early autumn, multi-services cover crops trap mineral nitrogen from the soil before the drainage period. For this reason, they are one of the tools in the Nitrate Directive to limit nitrate pollution of aquifers coming from agriculture. Cover crops are very effective to limit these losses, up to 90% of reduction as compared to bare soil during the fallow period. This efficacy is increased when cover crop is non-legume (although legumes remain effective) and growing period is long. However, high biomass reduces drainage by increasing evapotranspiration, which can be a problem for water resource. Nevertheless, cover crops generally do not reduce available water for the subsequent cash crop, except if destruction is too late. At destruction, cover crops release mineral nitrogen, more quickly as their C/N is low and up to 50% of the nitrogen uptake within the following 6 months. Depending on the intensity of leaching and the amount of nitrogen absorbed by the cover crop, nitrogen pre-emptive effects can be observed, particularly in dry climate, requiring compensation with mineral fertilization. In the long term, a positive effect on the subsequent crop is observed, due to a higher organic matter content of the soil and increased mineralization. To better combine the different services offered by cover crops, local adaptation is needed, according to the pedoclimatic conditions and specific objectives during fallow period.