Changes in soil acidity from 1927 to 1982–1984 in a forest area of south‐west Sweden

Abstract

Reinvestigation of 90 soil profiles sampled for pH measurements in 1927 revealed a general decrease in pH with 0.3-0.9 units (measured electrometrically on field-moist samples in water with the same ratio soil/water on both occasions). All soil horizons (A 0 , A 2 , B and the subsoil, C, at 70 cm depth) had become more acid beneath all types of canopy (beech, oak, spruce planted during different periods), but the spruce stands were on average more acid than the hardwoods. In the upper soil horizons (A o and A 2 ), old spruce stands were more acid than the young ones at both samplings, but this effect was small in the B horizon and absent in the C horizon. While the tree species effect and age effect in the spruce stands may be called biological acidification, the acidification of deeper horizons, now often below pH 4.5 and in the aluminium buffer range, seems difficult to explain without assuming an influence of acid deposition.

Decadal Changes in Potassium, Calcium, and Magnesium in a Deciduous Forest Soil

“…C ase studies of long-term soil change are becoming more common in the literature and are adding substantially to our knowledge about this important subject (Bailey et al, 2005;Falkenggren-Grerup and Eriksson, 1990;FalkenggrenGrerup and Tyler, 1992;Hallbacken and Tamm, 1986;Johnson et al, 1988Johnson et al, , 1994Johnson and Todd, 1990;Knoepp and Swank, 1994;Richter et al, 1994;Richter and Markewitz, 2001;Trettin et al, 1999). In polluted regions of the world, atmospheric deposition may play a major role in causing soil acidifi cation and decreases in exchangeable K + , Ca 2+ , and Mg 2+ (Falkenggren-Grerup and Eriksson, 1990;Hallbacken and Tamm, 1986;Johnson and Todd, 1990).…”

“…In polluted regions of the world, atmospheric deposition may play a major role in causing soil acidifi cation and decreases in exchangeable K + , Ca 2+ , and Mg 2+ (Falkenggren-Grerup and Eriksson, 1990;Hallbacken and Tamm, 1986;Johnson and Todd, 1990). Uptake and accumulation in tree biomass can also be a signifi cant cause of soil change, especially when the site is occupied by species with high Ca concentrations in their biomass (Alban, 1982;Johnson et al, 1988;Johnson and Todd, 1990;Richter and Markewitz, 2001;Trettin et al, 1999).…”

Rhizospheric P and K in forest soil manipulated with ammonium sulfate and water

“…Temporal approaches (e.g. Hallbäcken and Tamm 1986) and spatial approaches are often combined and may yield general low resolution information from which trends in ecosystems may be identified. Similarly, microcosm approaches (e.g.…”

Impact Models to Assess Regional Acidification

“…However, silicates are likely to dominate completely in soil layers surrounding strongly acid lakes, and there the weathering rate may thus be more or less independent of the acid deposition. Moreover, recent analyses of soil from areas in southern Sweden, where such lakes are common, show that exchangeable cations are strongly depleted (Hallbacken and Tamm, 1986;/:i'alkengren-Grerup et al, 1987), which means that ion exchange processes must be relatively insignificant there today. It thus turns out that the concentration of nonmarine calcium plus magnesium in many of Sweden's strongly acid lakes is quite low (usually < 200~eq 1-1).…”