A long-term soil moisture monitoring network in Twente, the Netherlands: observations, applications, and perspectives

The ITC Faculty at the University of Twente operates a soil moisture monitoring network consisting of approximately 20 stations that continuously measure volumetric soil water content and soil temperature at up to five depths between 5 and 80 cm. The network was originally established in 2009; over time, several stations have been removed, while others have been added. Its initial purpose was to support the calibration and validation of satellite-based soil moisture products. Recent applications use soil moisture and groundwater monitoring to support adapted water management practices, including adjustable weirs and controlled drainage. For this purpose, supplementary soil moisture stations have been installed in smaller clusters within projects conducted in collaboration with local farmers and the regional water authority Vechtstromen. The quality-checked dataset from 2009-2020 has been published by van der Velde et al. (2023) and also added to the International Soil Moisture Network (ISMN). Furthermore, real-time and historical soil moisture data contribute to the Dutch drought portal. Recently, the soil moisture network has been integrated into the development of a larger multi-sensor infrastructure at the ITC, supported by the NWO-funded Sectorplan in Earth and Environmental Sciences.The collected data will be analyzed to investigate long-term trends, responses to meteorological extremes, and spatial variability in soil moisture across the Twente region. Furthermore, data from soil moisture, meteorological, groundwater, and additional sensors, together with remote sensing observations, will serve as calibration and validation data for an integrated hydrological model. This framework aims to investigate the effects of local agricultural water management practices on water fluxes and water balance components, such as evapotranspiration, groundwater recharge, and surface runoff, and to scale up field-level adaptation measures and their effects to the regional scale. Insights from these investigations are expected to support the identification of sustainable and resilient water management practices from field to regional scales, helping to better cope with increasing water-related challenges such as droughts and flooding.References: van der Velde, R., Benninga, H.-J. F., Retsios, B., Vermunt, P. C., and Salama, M. S.: Twelve years of profile soil moisture and temperature measurements in Twente, the Netherlands, Earth Syst. Sci. Data, 15, 1889–1910, https://doi.org/10.5194/essd-15-1889-2023, 2023.