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Soil acidification: comparison of acid deposition from the atmosphere with inputs from the litter/soil organic layer

1995; Elsevier BV; Volume: 66; Issue: 1-2 Linguagem: Inglês

10.1016/0016-7061(94)00071-h

1872-6259

Claire N. Gower, David L. Rowell, Stephen Nortcliff, A. Wild,

Peatlands and Wetlands Ecology

At three relatively unpolluted sites in beech (Fagus sylvatica) woodlands on the Chiltern Hills of southern England, measurements were made over one year of the amount and composition of precipitation, throughfall, stemflow, and drainage below the soil organic layer. At two sites the soils were acidic and at the third the soil contained calcium carbonate. Comparison was made between the soil acidification potential (A.P.) of throughfall calculated as (H+ + 2NH4+) and the A.P. of the drainage water from the soil organic layer calculated as the difference between the sum of cations and the sum of Cl−, SO42− and NO3−, that is, as HCO3− + organic anions. In the two woodlands with acidic soil the A.P. of throughfall was 198 mmolc m−2 a−1 and that of the drainage water was 224 mmolc m−2 a−1; the corresponding figures for the woodland with calcareous soil were 176 and 511 mmolc m−2 a−1. The increases in the drainage water are attributed mainly to organic anions in the acidic soils and bicarbonate in the calcareous soil. The relative importance of the components in throughfall and the organic anions in drainage from the soil organic layer is discussed in relation to soil acidification.