English Abstract Annual inventories carried out in the Netherlands
indicate that 50% of the national forests is damaged. One of the measures
that could possibly counteract the effects of acidic depostion is forest
liming. Experimental liming plots are made in St. Anthonis (Peel region)
and Harderwijk to study the effects of forest liming. This report evaluates
measurements during 1 year after liming on plots near St. Anthonis and a
one-time inventory of the soil solution composition 3 years after liming on
the plots near Harderwijk. The results from the St. Anthonis site show a
significant relationship between forest liming and nitrate leaching. Due to
other processes in the saturated zone (such as denitrification) the net
effect is only a minor increase of the groundwater nitrate concentration.
The measurements at the Harderwijk site do not indicate nitrate leaching due
to liming but a one time inventory of soil solution is too small a basis for
conclusions on long term effects. The increase of nitrate leaching due to
liming probably depends largely on local factors such as soil type,
groundwater level and organic matter content.
