Synopses & Reviews
Synopsis
Foreword1. Study context and methodology1.1. Fallow period: definition, management practices and regulatory aspects1.2. Study objectives and approach2. Main lessons drawn from the study of the literature2.1. Cover crop management techniques2.2. Nitrate and water during fallow periods2.3. Effects of cover crops on erosion, physical soil properties and carbon balance2.4. Biotic effects of cover crops on weeds, microflora and fauna2.5. Conclusion: a rich but incomplete analysis of the literature3. Main lessons drawn from the simulation study3.1. Objectives of the simulation study using a dynamic crop model3.2. Methodology of the three parts of the simulation study3.3. Generic and specific lessons drawn from the simulation study3.4. Discussion of study results4. Conclusions and outlook
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Synopsis
This study, based on a literature review and simulations, shows the efficiency of cover crops at catching nitrate in most agriculture situations. It also analyzes both the negative impacts they can have and the ecosystem services they can provide. The introduction of a cover crop between two main crops helps catch the soil mineral nitrogen before the period of drainage and consequently reduces nitrate leaching and nitrate concentration in the drainage water. This study allows quantifying the efficiency of cover crops at catching nitrate and optimizing their implantation conditions over a large range of French pedoclimatic conditions. The presence of high nitrate levels in surface and ground waters, due to excessive nitrogen fertilization and natural production of nitrate by soil organic matter mineralization, is a double challenge for public health and environment protection.