Subproject 7 – Hydrological cycling
Monitoring and modeling of water and related nutrient fluxes in rice-based cropping systems
Subproject SP7 investigates the impact of crop management (mulching, cover crop) and cropping patterns (R-WET wet rice/wet rice, R-MIX wet rice/dry rice, M-MIX wet rice/maize) on water and water related nitrogen fluxes. Within Phase II we focus part of our research on cracks by a set of field experimental approaches including electrical resistivity tomography, crack-o-meter sampling, and geometric measurements. These experiments are part of a wider joint crack experiment in which all other subprojects participate and which is organized by SP7. Further, we will continue our routine measurements using the automatic sampling system. We will concentrate on the partitioning of evaporation and transpiration by means of vertical profiling of stable water vapor isotopes and associated measurements of stable water isotopes in soil, plant, and ponding water. All field experimental results will be used to parameterize and validate CMF, for which a number of double-porosity models will be tested to identify the most appropriate approach to consider dynamic cracks. Finally, the revised CMF will be used for the simulation of hydrological fluxes on the ICON core sites as well as on additional IRRI MET sites. In a joint effort with SP6, we will regionalize water and associated N fluxes along with trace gas emissions and run virtual catchment experiments to investigate landscape relevant fluxes.
Investigators:
Prof. Dr. Johan A. Huisman
Institution:
Institute for Landscape Ecology and Resources Management
Justus Liebig University Giessen
Heinrich-Buff-Ring 26
D-35392 Giessen, Germany
Institute for Bio- and Geosciences,
IBG 3 – Agrosphäre,
Forschungszentrum Jülich GmbH,
52425 Jülich, Germany