Effects of acidification and its mitigation with lime and wood ash on forest soil processes in southern Sweden. A Joint Multidisciplinary Study A Joint Multidisciplinary Study

• Main Authors: Lundström, Ulla, Bain, D C, Taylor, A F, Van Hees, P A, Geibe, Christine E, Holmström, Sara J, Melkerud, P A, Finlay, R, Jones, D. L., Nyberg, L, Gustafsson, J P, Riise, G, Tau Strand, L
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Nature 2003
• Subjects: Air and Soil Pollution; Chemical Sciences; Chemistry; Focus; Kemi; Natural Sciences; Naturvetenskap; Water; Northern Sweden
• Online Access: https://doi.org/10.1023/A:1024131615011; https://researchportal.murdoch.edu.au/esploro/outputs/journalArticle/Effects-of-acidification-and-its-mitigation/991005560425207891

A joint multidisciplinary investigation was undertaken to study the effects of lime and wood ash applications on two Norway spruce forest Spodosolic soils. The two sites, typical for southern Sweden, were treated in 1994 with either 3.25 t ha-1 dolomite or 4.28 t ha-1 wood ash (Horröd site) or in 1984 with either 3.45 or 8.75 t ha-1 dolomite (Hasslöv site). Both sites show signs of acidification by atmospheric anthropogenic deposition and possessed low soil pH(4.3) and high concentrations of inorganic Al (35 μM) in the upper illuvial soil solution. The prevailing soil conditions indicated perturbed soil processes. Following treatment with lime or wood ash, the soil conditions were dramatically altered. Cation exchange capacity (CEC) and base saturation (BS) was considerable increased after addition. Four years after application most of the added Ca and Mg was still present in the mor layer. Fifteen years after application,Mg in particular, became integrated deeper in the soil profile with a greater proportion lost by leaching in comparison to Ca. The concentrations of these ions were greatest in the mor layer soil solutions and Mg had higher mobility giving higher concentrations also deeper in the profile. Four years after treatment, the application of wood ash and lime resulted in lower pH values and higher inorganic Al in mineral subsoil solutions compared to the untreated soil. We hypothesize that this was probably due to an increased flow of hydrogen ions from the upper soil as a result of displacement by Ca and Mg ionsin the enlarged exchangeable pool. In contrast, fifteen years after lime and wood ash application, the mineral subsoil horizons possessed a higher pH and lower soil solution Al content than the untreated plots.Liming promoted soil microbial activity increasing soil respiration 10 to 36%. This is in the same range as net carbon exchange for forests in northern Sweden and could potentially have a climatological impact. The turnover of low molecular weight organic acids (LMWOA) by the soil ...