Denitrification in relation to soil nitrite and nitrate dynamics – towards source differentiation in undisturbed soil

点击翻译按钮获取中文摘要

In DASIM phase I the project P5 focused on the characterization of the simultaneously occurring gross nitrogen dynamics in laboratory experiments with repacked soil with and without hot spots. A laboratory incubation method at reduced N2 atmosphere was developed and carried out to increase the sensitivity of N2 flux measurements. Different labeling options, including the 15N triple labelling method, dual 18O-15N labelling and isotopomer studies were carried out in parallel and are currently evaluated. In phase II (this application) measurements will move to the field. P5 is responsible for the central experiment CE-GI on permanent grassland where the methods that were tested and developed in phase I will be carried out under field conditions. P5 will test and develop suitable labeling techniques and will also carry out 18O labelling studies in the field as well as soil core studies to support field data. CE-GI will interact with most P’s and cooperates intensively with PC to develop numerical analysis techniques for the analysis of data sets generated within DASIM. The soil structure of the Giessen soil will be evaluated in collaboration with P1. Full data sets obtained will serve as validation data for the models developed in P7 and P8 of the DASIM RU.