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The role of SO4-Reduction and spatial Heterogeneity of Soil SO4 Pools for the Reversibility of Soil and Water Acidification
BITÖK-S 6From 01/1995 to 12/1997
Principal Investigator: Egbert Matzner
Staff: Christine Alewell, Claudia Jungnickel, Bernhard Manderscheid, Thomas Schweisser
Grant: 0339476 B Vorhersage und Erklärung des Verhaltens und der Belastbarkeit von Ökosystemen unter veränderten Umweltbedingungen
To predict the recovery of soil solution and runoff acidification under decreasing S deposition, the spatial heterogeneity of SO42- sorption isotherm parameters as well as SO42- desorption from deeper soil layers in 1 - 10 m depth were investigated at the catchment Lehstenbach. The spatial heterogeneity of the isotherm parameters in the soil was found rather high which effects the prognosis of recovery significantly. Relations between sulfate sorption parameters in soils and other soil chemical properties were weak.
The SO42- storage of the deeply weathered granite bedrock was much higher (90 kmol/ ha up to 10 m depth) as compared to the soil (15 kmol/ha up to 50 cm depth). Simulation models indicated that the weathered lithosphere in the Lehstenbach catchment acts as a long lasting SO42- buffer for groundwater in response to decreasing S-deposition.
We found low temporal and spatial heterogeneity in the d34S values of the SO42- input via throughfall but a large spatial and temporal heterogeneity for d34S in soil solutions and concluded that the soil is a reactive pool for SO42- which creates heterogeneity of the isotopic signature. Stable isotope data clearly showed that SO42- is not inert to biological processes. While d34S values in soil solutions of the intermittent seep was distinctly enriched in 34S, indicating S-reduction, SO42- in soil solutions of terrestrial forest soils were slightly depleted, which points to the influence of SO42- mineralisation. The effect of sulfate reduction on the overall S-budget of the watershed seems to be low.
Different modeling approaches to predict sulfate dynamics and soil solution chemistry were compared. Objective parameters to evaluate model performance were used and developed. Furthermore an attempt was made, to define the term valid model for a system. (final report 1998)
List of publications of this Project
|Groscheová, H; Novák, M; Alewell, C: Changes in the d34S ratio of pore-water sulfate in incubated sphagnum peat, Wetlands, 20/1, 62-69 (2000) -- Details|
|Alewell, C: Investigating sulfate sorption and desorption of acid forest soils with special consideration of soil structure, Z. Pflanzenernährung Bodenkunde, 161, 73-80 (1998) -- Details|
|Alewell, C; Manderscheid, B: Use of objective criteria for the assessment of biogeochemical ecosystem models, Ecological Modelling, 107, 213-224 (1998) -- Details|
|Alewell, C; Bredemeier, M; Matzner, E; Blanck, K: Soil solution response to experimentally reduced acid deposition in a forest ecosystem, J. Environmental Quality, 26, 658-665 (1997) -- Details|
|Alewell, C; Giesemann, A: Sulfate reduction in a forested catchment as indicated by d34S values of sulfate in soil solutions and runoff, Isotopes Environm. Health Studies, 32, 203-210 (1996) -- Details|
|Alewell, C; Matzner, E: Water, NaHCO3-, NaH2PO4- and NaCl-extractable SO42- in acid forest soils, Z. Pflanzenernährung Bodenkunde, 159, 235-240 (1996) -- Details|
|Matzner, E; Alewell, C: Zur Abschätzung der zukünftigen Entwicklung der Grundwasserversauerung, Informationsberichte des Bayerischen Landesamtes für Wasserwirtschaft, 3/95, 271-280 (1995)|
|Lükewille, A; Malessa, V; Alewell, C: Measured and modelled retention of inorganic sulfur in soils and bedrock (Harz Mountains, Germany), Water, Air and Soil Pollution, 85, 683-688 (1995) -- Details|
|Alewell, C; Manderscheid, B; Lükewille, A; Koeppe, P; Prenzel, J: Describing Soil SO42- dynamics in the solling roof project with two different modelling approaches, Water, Air and Soil Pollution, 85, 1801-1806 (1995) -- Details|
|Alewell, C: Sulfat-Dynamik in sauren Waldböden - Sorptionsverhalten und Prognose bei nachlassenden Depositionen in Bayreuther Institut für Terrestrische Ökosystemforschung (BITÖK): Bayreuther Forum Ökologie, Selbstverlag, 19, 1-185 (1995) -- Details|
|Alewell, C; Matzner, E; Bredemeier, M: Reversibility of sulfate sorption in acid forest soils: a transfer of laboratory studies to the field with MAGIC, Informationsberichte des Bayerischen Landesamtes für Wasserwirtschaft, 3/95, 171-173 (1995)|