Carbon sequestration potential of soils in southeast Germany derived from stable soil organic carbon saturation

• Published in: Global change biology Vol. 20; no. 2; pp. 653 - 665
• Main Authors: Wiesmeier, Martin, Hübner, Rico, Spörlein, Peter, Geuß, Uwe, Hangen, Edzard, Reischl, Arthur, Schilling, Bernd, von Lützow, Margit, Kögel-Knabner, Ingrid
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.02.2014; Wiley-Blackwell
• Subjects: agricultural management; Agriculture; Agronomy. Soil science and plant productions; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Carbon - analysis; Carbon Sequestration; climate change; Climatology. Bioclimatology. Climate change; CO2 mitigation; Earth, ocean, space; Ecosystem; Exact sciences and technology; External geophysics; Fundamental and applied biological sciences. Psychology; General agroecology; General agroecology. Agricultural and farming systems. Agricultural development. Rural area planning. Landscaping; General agronomy. Plant production; General aspects; Generalities. Agricultural and farming systems. Agricultural development; Germany; Meteorology; Soil - chemistry; soil fractionation; soil organic carbon stocks; Soil sciences; stabilization of soil organic matter; Central Europe; Europe; Germany; Germany, Bavaria; Organic carbon; Fractionation; Organic matter; mitigation; Stabilization; Carbon dioxide; stabilization of soil organic matter; CO; Carbon sequestration; Dynamical climatology; Climate change; Soils; soil fractionation; soil organic carbon stocks; Mitigation measure; Agriculture; agricultural management; Stock; CO2 mitigation; climate change
• ISSN: 1354-1013; 1365-2486
• DOI: 10.1111/gcb.12384

Sequestration of atmospheric carbon (C) in soils through improved management of forest and agricultural land is considered to have high potential for global CO2 mitigation. However, the potential of soils to sequester soil organic carbon (SOC) in a stable form, which is limited by the stabilization of SOC against microbial mineralization, is largely unknown. In this study, we estimated the C sequestration potential of soils in southeast Germany by calculating the potential SOC saturation of silt and clay particles according to Hassink [Plant and Soil 191 (1997) 77] on the basis of 516 soil profiles. The determination of the current SOC content of silt and clay fractions for major soil units and land uses allowed an estimation of the C saturation deficit corresponding to the long‐term C sequestration potential. The results showed that cropland soils have a low level of C saturation of around 50% and could store considerable amounts of additional SOC. A relatively high C sequestration potential was also determined for grassland soils. In contrast, forest soils had a low C sequestration potential as they were almost C saturated. A high proportion of sites with a high degree of apparent oversaturation revealed that in acidic, coarse‐textured soils the relation to silt and clay is not suitable to estimate the stable C saturation. A strong correlation of the C saturation deficit with temperature and precipitation allowed a spatial estimation of the C sequestration potential for Bavaria. In total, about 395 Mt CO2‐equivalents could theoretically be stored in A horizons of cultivated soils – four times the annual emission of greenhouse gases in Bavaria. Although achieving the entire estimated C storage capacity is unrealistic, improved management of cultivated land could contribute significantly to CO2 mitigation. Moreover, increasing SOC stocks have additional benefits with respect to enhanced soil fertility and agricultural productivity.