70 



W. R. MULLER-STOLL AND G. LERCH 



basal container however, that much water was transferred upward, due to 

 the same temperature gradient (about io°C), that soil moisture in the upper 

 tube increased up to 4-2%. Thus, after twelve hours the initial soil moisture 

 in the upper containers had increased by approximately 50% compared 

 with the initial status. 



o 



u 



i" 40H 



^ 3-0- 

 o 2-8 - 





water bath 

 ■r^"/' / y /■ > ^ X /- 



basal soil column 



■50 



°C 



-40 



-30 



-20 



n 



120- 



110- 



I "^ I ' 1^1 



I I I I 



I ' I ^ I ' I ^ I ' I 



8 10 12 14 16 18 20t 



10 12 14 



Time on test day 



20hrs 



Fig. 2. Vapour condensation in bare soil due to temperature gradients. Initial water 

 contents in apical and basal soils respectively (a) 11%, 11%; (b) 2-8%, 11%; (c) 11%, 



Inverse experimental conditions -higher soil moisture (ii-o%) in the 

 apical tubes, dry soil (2-8%) below them- did not cause any change in the 

 water content of the apical soil columns (Fig. 2c). 



