TY - JOUR
T1 - Denitrification in a vertisol under long-term tillage and no-tillage management in dryland agricultural systems
T2 - Key genes and potential rates
AU - Melero, Sebastiana
AU - Pérez-de-Mora, Alfredo
AU - Murillo, José Manuel
AU - Buegger, Franz
AU - Kleinedam, Kristina
AU - Kublik, Susanne
AU - Vanderlinden, Karl
AU - Moreno, Felix
AU - Schloter, Michael
PY - 2011/3
Y1 - 2011/3
N2 - The impact of tillage practices on microbial N transformations in Vertisols is poorly understood and data from long-term field experiments are scarce, particularly in semiarid regions. We evaluated the effects of traditional tillage (TT) vs no-tillage (NT) on denitrification in a long-term field experiment under a rainfed crop rotation system (cereal-sunflower-legumes) on a Vertisol (SW Spain). In general, the abundance of denitrifiers and the respective potential denitrification rates was higher under NT compared to TT during the vegetation period, but not after harvesting. However differences in denitrifier numbers were within the same order of magnitude (0.5-3×107copiesgsoildw). The abundance of nitrite reducers and N2O reducers was relatively similar. In addition, N2O/N2 ratios between 1 and 2 were found for both treatments. These results emphasize that NT has a limited impact on denitrification in Vertisols under fertilizer regime and legume-crop rotation and thus losses of N2O are expected to be comparable to those of traditional tillage systems.
AB - The impact of tillage practices on microbial N transformations in Vertisols is poorly understood and data from long-term field experiments are scarce, particularly in semiarid regions. We evaluated the effects of traditional tillage (TT) vs no-tillage (NT) on denitrification in a long-term field experiment under a rainfed crop rotation system (cereal-sunflower-legumes) on a Vertisol (SW Spain). In general, the abundance of denitrifiers and the respective potential denitrification rates was higher under NT compared to TT during the vegetation period, but not after harvesting. However differences in denitrifier numbers were within the same order of magnitude (0.5-3×107copiesgsoildw). The abundance of nitrite reducers and N2O reducers was relatively similar. In addition, N2O/N2 ratios between 1 and 2 were found for both treatments. These results emphasize that NT has a limited impact on denitrification in Vertisols under fertilizer regime and legume-crop rotation and thus losses of N2O are expected to be comparable to those of traditional tillage systems.
KW - NO/N ratio
KW - NirK
KW - NirS
KW - NosZ
KW - Real-time PCR
UR - http://www.scopus.com/inward/record.url?scp=79951552204&partnerID=8YFLogxK
U2 - 10.1016/j.apsoil.2010.12.003
DO - 10.1016/j.apsoil.2010.12.003
M3 - Article
AN - SCOPUS:79951552204
SN - 0929-1393
VL - 47
SP - 221
EP - 225
JO - Applied Soil Ecology
JF - Applied Soil Ecology
IS - 3
ER -
