The results of a
literature study examining quantitative estimates of N2O emission
rates are presented for a range of land-uses across Europe. The analysis shows
that the highest N2O emission rates are for agricultural lands
compared to forests and grasslands. The main factors regulating these rates are
available mineral nitrogen, soil temperature, soil water content and the
available labile organic compounds. These controls operate across different
time-scales, all must exceed a certain threshold for N2O emission to
occur. The results support the need for an emission factor function of land-use
and climate within models describing nitrogen dynamics in catchments. This would
allow the assessment of the net N2O emission within catchments in
terms of current levels and potential changes associated with climate
variability, climate change and land use change.
Keywords: nitrous oxide, soil water content, inorganic N, soil temperature,
ecosystems, land-use management, soil type |