Regional soil moisture networks have been installed in the two study regions Kraichgau and Central Swabian Alb which continuously provide data on soil water contents and soil temperature in 15 cm depth as well as precipitation amounts from 21 monitoring sites in each region.

The monitoring stations were established in an outer (27x27 km²), a central (9x9 km²) and an inner grid (3x3 km²). All stations are located on agricultural fields. In the Kraichgau region, they consist mainly of winter wheat, spring barley, and winter rape fields. In the Swabian Alb region, also triticale, spelt, and oat fields are included. Soil water contents is measured by so-called TDT (Time Domain Transmission) sensors. Measuring length of this cable sensor in the soil is 3 m. The measuring volume of approx. 6 L is clearly bigger than that of a classical TDR (Time Domain Reflectometry) sensor. Data are transferred to a central data server in Hohenheim by GPRS and internet and can be accessed by the public (link). The cooperation of 34 farmers owning the fields of this networks is greatly acknowledged.