Identification of the dissimilatory nitrate reduction into ammonium (DNRA) activity in grassland soils and quantification of gross nitrogen transformation rates (T. Cugnon)
The DNRA was first assumed to only occur in water environment but we now have proof that it also occurs under soil conditions, and this reaction has the big interest that it maintains nitrogen in the cycle. The objectives of this work are to identify the presence of the bacterial Nrf-a gene in soils by using PCR, to quantify the rates of the various paths of nitrate reduction in the nitrogen cycle by using labeled nitrogen, and to identify some bacterial clades involved in the DNRA reaction by using metagenomics.
Prediction of the nitrogen soil mineralization potential using anaerobic incubation (T. Cugnon)
The amount of nitrogen which could be provided by the soil mineralization is quite difficult to estimate, due to the heterogeneity of the soils and the environmental factors. This project aims to validate a better way of prediction based on anaerobic incubation of a diversity of Walloon soils. We are monitoring the real mineralization on different kinds of soils and crops to correlate it with our prediction. The final objective is also to predict this potential by using near infrared spectroscopy.
Collaborations: ELIA-Nitrawal, Laboratoires du réseau Requasud.