Research Project: DRIeR
Drought processes, impacts and resilience: making the invisible visible (DRIeR)
Drought is a natural phenomenon that is part of the natural climate cycle and which occurs at irregular intervals. For example, recent droughts took place in Southwestern Germany during the years 1976, 2003 and especially in 2018. Droughts are complex phenomena with wide-ranging environmental and socioeconomic impacts. Most frequently reported impacts in Southwestern Germany are adverse effects on the hydrological cycle (e.g., deficits in streamflow and groundwater), on the agricultural sector (e.g., harvest losses or even failures), on water quality, and on the public water supply. With climate scenarios pointing towards a future increase in drought occurrence, even in the temperate climate zones, the severity and frequency of these drought impacts is likely to increase as well.
DRIeR is a research project within the “Network Water” initiated and funded by the German federal state of Baden-Württemberg over a period of five years (2016-2020). According to the multifaceted and complex nature of droughts, DRIeR is organized in an interdisciplinary way. Thus, natural and social scientists of the universities of Freiburg, Tübingen and Heidelberg as well as a large number of stakeholders, governmental and private actors work together in DRIeR.
The overall project aims are the following:
- an interdisciplinary analysis of historic and recent drought events
- the enhanced collaboration between science, stakeholders and local actors in order to develop adaptation and coping strategies with regard to droughts
- the development of a public drought information and cooperation platform
- a better international visibility of water research in Baden-Württemberg
Our group’s research focus is on the analysis of drought impacts on landscape hydrology and soil nutrient fluxes. On field experimental plots we investigate evapotranspiration, soil water fluxes and groundwater recharge as well as concentrations of nitrate in the leaching, and we study their dynamics during and after drought events. These new experimental findings will support the further development of hydrological models, both at the plot and regional scale.
Currently, we carry out field experiments on two agricultural sites in Baden-Württemberg. There we measure nitrate concentrations of the soil water at different profile depths. The simultaneous measurement of soil physical properties, hydro-climatic variables and land use characteristics will help us to correlate the nutrient fluxes with their impact factors. Furthermore, our investigations include the analysis of long-term water and nitrate fluxes at a forest monitoring station in Rhineland-Palatinate.
The results of our field research support the further development of the hydrological model TRAIN. Beside the development of a specific module to simulate soil nitrate fluxes, the model is applied at different research sites as well as on the regional scale. Currently, we apply the model for the simulation of the water fluxes in Rhineland-Palatinate as well as in Baden-Württemberg. The ongoing investigations for the period 1961-2018 focus on the simulated dynamics of the different elements of the water balance during drought events.