The Continental Region is represented by the arc north of Lake Geneva in the Romandy region in western Switzerland. In contrast to other pilot region, this region is characterized by low animal production, and arable cropping is predominant. Arable crops and grass cuttings are mostly exported as feed to more animal-dense areas of Switzerland. With low animal stocks, nutrients have to be imported as manure or fertilizer. As nutrient imports can be expensive, the nutrient exports are expected to exceed the nutrient imports, resulting in nutrient deficits and imbalanced nutrient supply.
NutriBudget is collaborating with both conventional and organic farms in the pilot region, and both farming systems will be included in the study. In organic farming, nutrient imports are further restricted in amount and origin. Therefore, the nutrient imbalances are expected to be more profound on organic farming compared to conventional farms.
As part of the NutriBudget project, the pilot aims to optimize nutrient use through a detailed analysis of the current state in the first year and field experiments as well as modelling based on these results in the following 2 years. The mitigation measures may include:
Improved nutrient planning: Through calculations of the current nutrient import-export balance of the farms, nutrient imbalances will be revealed. This will aid in a better theoretical understanding of the nutrient flows in the area.
Reduced/adapted fertilizer input: Based on deficits or surpluses found in the first step, nutrient inputs will be adapted, thus increased or decreased. The ratios of exchangeable cations can vary depending on the fertilizer inputs. This strongly affects the release of nutrients from the soil buffering capacity. Fertilizer inputs will therefore additionally be adapted to optimize cation ratios in the soil.
Use of bio-based fertilizer (BBF): Bio based fertilizers are based on renewable material such as food-processing waste. BBF are a source of both nutrients and organic carbon. Optimizing the use of BBF to crop requirements allows sufficient supply of nutrients and maintaining soil organic carbon while re-using waste products and thus transitioning toward to a more circular economy.
Fertilizer placement: Fertilizer placement has a strong effect on nutrient use efficiency, especially for immobile nutrients such as phosphorus. Precision fertilization may thus reduce the fertilizer use compared to broadcasting.