Nitrogen dynamics in deep ploughed soils of North Germany

Rolf Nieder1, Zaur Jumshudov1, Viridiana Alcántara2, Axel Don2, Reinhard Well2

1Institute of Geoecology, Technische Universität Braunschweig, Langer Kamp 19c, Braunschweig 38106, 

  Germany, [email protected]

2Thünen Institute of Climate-Smart Agriculture, Bundesallee 50, Braunschweig 38116, Germany

Abstract

On average 45 years after the deep ploughing operation, deep ploughed soils contained 24±5% more total N compared to conventionally ploughed reference soils. However, the mean N stock in the new topsoils was still 8% lower compared to the reference soils. This indicates a long-term N accumulation potential lasting more than 4-5 decades. The potential N mineralization and nitrification capacities of loamy deep ploughed soils were higher compared to sandy deep ploughed soils. All sites showed very low N mineralization potentials and nitrification capacities in the buried Ap material compared to surface Ap horizons.