Large-scale assessment of optimal emergence and destruction dates for cover crops to reduce nitrate leaching in temperate conditions using the STICS soil–crop model

摘要: Abstract Cover crops can be an efficient agricultural practice to reduce nitrate leaching during the fallow period and decrease pollution of aquifers. For maximum reduction leaching, cover-crop management must adapted pedoclimatic context. We used soil–crop model STICS assess optimal emergence dates in summer destruction autumn winter for three species cover (mustard, ryegrass vetch) at a large scale France. first calibrated validated STICS’s predictions soil crop dynamics under wide range conditions, including bare crops. Since were sufficiently accurate, we then predicted impact several on 24 contrasting climatic sites over 20 years. These represented conditions found France much Europe. Using generalized linear (GLM), extrapolated vulnerable zones sites. defined date as allowing higher drained water those which high was that also avoided negative effects subsequent main resources. accurately mineral N from both calibration validation datasets, despite lower accuracy vetch simulations. Over 20-year simulations, varied, depending mainly site, year. Optimal earlier (late July) than (early August) mustard north (cold rainy) south (warm dry). dates, this paper, frequently between October December. Mean by site strongly correlated with characteristics tested, enabled us extrapolate them larger identify areas similar according species. Later occurred southeastern late August September, while earliest July early east The (October–December), later located temperature western coastal Atlantic Ocean