EFFECTS OF LIMING, FERTILIZATION AND ACIDIFICATION ON PH, SOIL-MOISTURE, AND ATP CONTENT OF SOIL FROM A SPRUCE FOREST IN SOUTHERN GERMANY

Short-term and medium-term effects of liming (CaCO3), fertilization [5 Ca(NO)3)2.NH4NO3], and acidification on soil bioactivity were measured in a spruce stand in Southern Germany. The experiment was set up in a randomized block design. Acid precipitation lowered the pH, liming in creased the pH, while fertilization caused only small alterations in p H values. Significant differences in soil moisture occurred only in th e mineral horizons. The soil ATP content of the humus layers decreased in all plots (control included) up to day 100. On all sampling dates, a pronounced decrease in ATP content followed the acidification. Mino r decreases in ATP were observed after fertilization, while liming pro duced no defined effects. Similar trends, but less pronounced, were ob served in the mineral horizons. Only a few significant correlations we re found between pH values and ATP or between moisture and ATP within a treatment and sampling date.