Nitrous oxide emissions from soils have been studied extensively during the last decade. Although only a small portion of these studies have been conducted in forests, there is considerable understanding about the effects of soil type, moisture, temperature and nitrogen concentrations on the emission patterns of N2O. However, the interactions between soil fauna, microbial community dynamics, root growth and decay, root activity and gas emissions are poorly understood. These parameters have a major impact on N2O-fluxes as they determine the availability of mineral nitrogen, which is the limiting factor for gaseous nitrogen losses in many non-agricultural ecosystems. In addition, some physical processes that determine gas flow to the atmosphere have received little consideration to date. It is postulated that forests will receive ever-greater attention in the future, as their area is increasing in many industrial states. Furthermore, forests play a major role in climate stabilisation, water management, and many provide an important source of renewable energy for the future. The aim of this paper is to point out some unresolved questions and less well studied aspects of nitrogen cycling in forest soils and their potential effects on N2O emission rates.
