Soil water tension

Soil water tension is measured automatically at pits 50, 100 and 160 with tensiometers (EQ2 Equitensiometer, Delta-T) combined to pressure transducers (TR2000A, Trans Instruments) which are further connected into serial data transmitters. There are automatic tensiometers also installed at different depths around the trees from which gas exchange is measured. Similar manually read tensiometers are used in pits 60, 70, 80 and 130 and measured with a Soilmetric pressure sensor. In the organic horizon smaller (SW041, Soil Measurement System) tensiometers are used.