Lauren Yabuki

The current global pressure for the achievement of competitive costs on crop production often leads to a misuse of fertilizers in agricultural areas that can cause severe contamination problems on soils, waters and atmosphere, affecting biodiversity and climate. Fertilization of crops with organic fertilizers such as liquid or solid manure (LSM) is a common practice throughout the world. However, when trying to reduce mineral fertilizer application, manure management can cause negative economic and environmental impacts. LSM increases soil organic carbon (SOC) levels and introduces a wide range of nutrients that improve soil quality and crop yields. However, repeated applications of organic fertilizers cause micronutrient accumulation in soil that generally does not result in increased micronutrient concentrations in field crops. Indeed, soil properties affecting micronutrient availability are of greater importance for crop accumulation. In the Ebro Valley (North-eastern Spain) intensive animal production is very important and generates high quantities of LSM. Therefore, a careful management of agricultural nutrients would be very relevant in this outstanding economic region. In this project, we will research the impact of mineral and organic fertilizers on micronutrients (copper and zinc) and nutrients (nitrogen and phosphorus) mobility in a Mediterranean agricultural maize field (Ebro valley, Spain). The effect of LSM addition on nutrients bioavailability will be systematically evaluated by one dynamic, in situ technique – Diffusive Gradients in Thin Films (DGT) – and conventional soil extraction methods using the three commonly extractants: acetic acid (HAc), ethylenediamine tetraacetic acid (EDTA), and calcium chloride (CaCl2). This project seeks to achieve improved crop fertilization strategies, especially in maize and its companion crops, to increase the sustainability of the cropping system.