Recovery of soil pH, cation-exchange capacity and the saturation of exchange sites from stemflow-induced soil acidification in three Swedish beech (Fagus sylvatica L.) forests
G. Matschonat et U. Falkengren-grerup, Recovery of soil pH, cation-exchange capacity and the saturation of exchange sites from stemflow-induced soil acidification in three Swedish beech (Fagus sylvatica L.) forests, SC J FOR R, 15(1), 2000, pp. 39-48
Stemflow water acidifies the soil in beech stands impacted by atmospheric d
eposition. To investigate whether the soil recovers from acidification, ste
mflow was experimentally removed. A horizon material was sampled at a dista
nce of 10-250 cm From the stems. Before the onset of the experiment, there
were stemflow-induced gradients in the saturation of exchange sites with K, H+ and Na+ that were larger near the stems, while the pH(KCl), the cation
-exchange capacity, and the saturation with Ca2+, Mg2+ and Mn2+ were smalle
r. After 8 yrs of recovery, the pH(KCl) and the saturation with Ca2+ and Mg
2+ had increased close to the stems, while the saturation with Na+, H+, Mn2
+ and Fe2+ and the C/N ratio had decreased. With some exceptions, e.g. base
saturation, the recovery was not complete after 8 yrs. Soil far from stems
had also changed similarly, probably because of the ongoing decrease in ov
erall deposition in southern Sweden.