Recovery from acidification in central Europe -: observed and predicted changes of soil and streamwater chemistry in the Lysina. catchment, Czech Republic

The geochemical model MAGIC was applied to estimate streamwater and soil chemistry between 1851 and 2030 at the Lysina catchment, an acid-sensitive granitic catchment covered by planted Norway spruce monoculture in the western Czech Republic, The total deposition of sulfur to the catclurient was 164 rneq M-2 in 1991, but had declined to 52 meq M-2 by 2000. Although S02 emissions in the region declined by 90% compared to the 1980s, acidification recovery was small within the period 1990-2000. Stream pH increased only slightly (from 3.92 to 4.07), although SO(4) concentration declined sharply from 568 mueq l(-1) (1990) to 232 mueq l(-1) (2000). Organic acids played an important role in streamwater buffering. According to the MAGIC prediction using deposition measured in 1999 2000, streamwater pH will increase to 4.3 and soil base saturation will increase to 6.2% by 2030 (from 5.7% in 2002). Pre-industrial pH was estimated to be 5.5 and soil base saturation 24.7%. The loss of base cations (Ca, Mg, Na, K) was caused predominantly by atmospheric acidity, but intensive forestry was responsible for approximately one third of the net base cation loss via accumulation in harvested biomass. Severely damaged sites, under continued pressure from forestry, will not return to a good environmental status in the near future (if ever) when the acid deposition input is only partially reduced. (C) 2002 Elsevier Science Ltd. All rights reserved.