“…However, most GHG studies have been conducted in the North Amazonia region (Neill et al, 2005;Carmo et al, 2007), while only few studies have attempted to evaluate the influence of different soil management practices on N 2 O emissions and to identify the main soil and environmental driving factors determining N 2 O emissions in subtropical agricultural systems of Southern Brazil (Pavei, 2005;Giacomini et al, 2006;Jantalia et al, 2008). In Southern Brazil, 8 Mha are cultivated with annual crops and the use of cover crops-based cropping systems has substantially increased in the last years as a consequence of the adoption of conservation practices, mainly no-tillage (Mielniczuk et al, 2003).…”