Teaching knowledge on nutrient fluxes in agroecosystems so as to maximize nutrient use efficiency by crops and minimize losses to the environment while providing optimal nutrient supply to crops. Methods to establish nutrient budgets are presented. Nutrient input and output variables (e.g. losses by various pathways) are treated and their optimal management presented.
At the end of the lecture the students can establish nutrient budgets, can critically evaluate agricultural systems as source of elements for the environment and can propose agricultural practices that limit these losses while maximizing nutrient use efficiency and optimizing nutrient supply to crops.
This course provides understanding of nutrient fluxes in agro-ecosystems so as to maximize nutrient use efficiency by crops while minimizing nutrient losses to the environment at optimal nutrient supply to the crop. First, different approaches to calculate nutrient budgets at various levels of the agro-ecosystem will be studied. Then the characteristics of input and output variables will be treated. These variables encompass organic (e.g. animal manure, plant residues, recycled organic wastes) and mineral fertilizers (e.g. minerals and products from recycling), symbiotic nitrogen fixation, nutrient deposition and pathways of nutrient losses. Measures to mitigate nutrient losses to the environment will be presented. Using case studies on nutrient rich and nutrient poor agro-ecosystems, strategies for an optimal nutrient management will be discussed that integrate attributes of soils, plants and fertilizers.