Nitrogen cycling in terrestrial ecosystems is complex and includes microbial processes such as mineralization, nitrification and denitrification, plant pyhsiological processes (e.g. nitrogen uptake and assimilation) and physiochemical processes (leaching, volatilization). In order to understand the challanges nitrogen puts to the environment, a through understanding of all these processes is needed. This chapter provides an overview about processes relating to ecosystem nitrogen input and output and turnover. On the basis of examples and literature reviews, current knowlege on the effects of nitrogen on ecosystem functions is summarized, including plant and microbial processes, nitrate leaching and trace gas emissions. Nitrogen cycling and nitrogen stocks in terrestrial ecosystems significantly differ between different ecosystem types (arable, grassland, chrubland, forests).
114.13 (Luft und Gase im Boden; Bodenatmosphäre; Bodenatmung) 114.61 (Gärungsbakterien. Nitrifikation, Denitrifikation usw.) 181.45 (Einflüsse durch Verunreinigungen der Umwelt) 114.261 (Stickstoff und Stickstoffverbindungen)
