SSS41

Denitrification in soils under field conditions - advances in quantification, controlling factors and process-based modelling
Convener: R. Well  | Co-Convener: KBB Butterbach-Bahl 
Oral Programme
 / Wed, 22 Apr, 10:30–12:00  / Room 2
Poster Programme
 / Attendance Wed, 22 Apr, 17:30–19:00  / Hall A
Denitrification plays a key role in the soil N cycle due to its implication for losses of reactive N from soil and emission of gaseous N-oxides to the atmosphere. Despite a long research history on soil denitrification and numerous recent technological advances, we still lack a comprehensive, quantitative understanding of denitrification rates in soils. This is in part due to methodical difficulties in measuring N2 production and emission at atmospheric background concentrations of 78%. Because controlling factors of soil denitrification have been mostly investigated under laboratory conditions, the effective control at the field scale and the spatial variability of denitrification on a landscape scale is still not satisfactorily clarified. Due to the lack of suitable data-sets, process-based denitrification models have rarely been validated and results of their application on site and regional scales are highly uncertain. Recent technological advances in measurements of N2 fluxes and linking structure and activity of denitrifying microbial communities with denitrification rates offer new opportunities in this area. We invite contributions from the following fields:
Methodical advances in measuring and modelling of denitrification in soils; measuring N2 and N2O fluxes from denitrification and controlling factors under field-like conditions using quantitative methods like incubation under He atmosphere, 15N-Tracer technique or high precision N2/Ar ratios; method comparisons; process-based modelling of denitrification at various scales; linking denitrification rates to parameters of the denitrifying community.