Variables Description################ *patchLabelBETAFOR: unique BETA-FOR patch label *subPatch: number of the sub-patch where the measurement was performed *dwc:decimalLatitude: latitudinal coordinates of the patch in decimals *dwc:decimalLongitude: longitudinal coordinates of the patch in decimals *dwc:samplingProtocol: The way the samples were taken *startSampling: The date when the sampling period started *endSampling: The date when the sampling period ended *dwc:measurementType: The nature of the measurement, in this case soil pH *dwc:measurementMethod: A description of the method or protocol used to determine the measurement *pH: determined pH value *temp: temperature at which the pH value was measured *dwc:measurementDeterminedBy: person who performed the measurement

At each Subpatch in the Bavarian Forest and University Forest Sailershausen, we took a soil core with 10 cm depth and 5 cm diameter. It is important to note that we only roughly removed litter and the soil cores include organic and mineral soil together. After sieving at 2 mm (Sailershausen) / 4mm (Bavarian Forest), 10 g of air-dried soil was solved in 25 ml of 0.01 M CaCI2 solution, shaken and left for 1 h. Measurements were conducted with a pH meter according to the manual. pH- Meter: Orion Star™ A211 pH-Benchtop Meter. Measuring electrode: Orion™ ROSS Ultra™ Triode™ pH/ATC-KombinationselektrodeThermo Scientific™. The temperature at which the pH value of the individual samples was measured is documented in the data set.