Optimal nutrient supply is an essential prerequisite for yield and quality formation of plant products, as well as for maintaining soil fertility. Similarly, in livestock production, the supply of feed and nutrients is crucial for performance. However, agricultural roduction systems with high nitrogen input levels result in undesirable utrient surpluses and environmentally relevant emissions; due to nutrient low changes caused by fertilizer production and feed imports leading to nutrient cycle overload at the field, farm, and landscape levels in Germany and the EU. Moreover, legal regulations on agricultural roduction, farm documentation, reporting requirements, and societal demands for agricultural management are increasing. To address these challenges, increased nutrient efficiency, as well as appropriate economic and ecological goals are required. Digital systems can significantly contribute to the optimal nutrient supply of crops and livestock and reduce environmental nutrient emissions. This study aims to create conceptual frameworks and methodological approaches for the development of digital nutrient management systems. The results were directly incorporated and implemented into 11 the development of a web-based nutrient management system. Relevant knowledge was acquired through scientific monitoring of the development process of this software application, and the basic concept was refined incrementally. This dissertation comprises a technical analysis of the requirements for a nutrient management system, a description of the technical architecture, networking and data integration concepts, and the implementation and evaluation of field tests. Furthermore, concepts for the modeling and management of nutrient flows in value chains and on landscape levels are derived and scientifically substantiated.weiterlesen