Development of a method to derive groundwater levels in organic soils in Germany from Sentinel radar data
Greenhouse gas emissions from organic soils are strongly influenced by the groundwater level. Deriving groundwater levels from remote sensing data could strongly improve the spatial and temporal resolution of greenhouse gas emission estimates.
In Germany, drained organic soils emit large amounts of carbon dioxide (CO2) and contribute around 40 % to the greenhouse gas emissions from the sectors agriculture and land use, land use change and forestry (LULUCF). Rewetted, especially flooded, peatlands may show large methane (CH4) emissions. Groundwater level and soil moisture are crucial drivers for both CO2 and CH4 emissions. In this project we will test the applicability of remotely sensed radar data (C-band microwave) for the determination of groundwater levels and, in future, for the monitoring of mitigation measures.
We use both the data base of groundwater levels available at the Thünen Institute for Climate-Smart agriculture and data from ongoing projects to calibrate and validate the relationship between the radar signal (“backscatter”) and groundwater levels. A crucial step is the application of a semi-empirical method for the correction of vegetation effects on the backscatter coefficient for different land-use types. Besides estimating the groundwater level drained organic soils we will test whether radar data can be used to detect and quantify the area of mitigation measures (rewetting of peatlands, raising the groundwater levels in utilized peatlands).
8.2017 - 7.2019
Project status: ongoing