TY - JOUR
T1 - Soil organic carbon stocks, distribution, and composition affected by historic land use changes on adjacent sites
AU - Mueller, Carsten W.
AU - Koegel-Knabner, Ingrid
N1 - Funding Information:
Acknowledgements We would like to thank L. and E. Mueller and E. Walter for their energetic help on the field sites. For their help in the laboratory, we thank L. Wissing, M. Greiner, and H. Fechter. H. Knicker is acknowledged for her help with 13C-CPMAS NMR spectroscopy and W. Haeusler for the X-ray diffraction measurements of our clay samples. For the fast processing of our samples, we would like to thank Xiaomei Xu and S. Trumbore at the KECK Carbon Cycle AMS Facility in Irvine, CA, USA. We thank two anonymous reviewers for very helpful comments on the manuscript. The project was generously funded by the Helmholtz Association in the joint virtual institute VH-129 “Center for Stable Isotope Analysis in Ecosystem Research.”
PY - 2009/3
Y1 - 2009/3
N2 - Historic alterations in land use from forest to grassland and cropland to forest were used to determine impacts on carbon (C) stocks and distribution and soil organic matter (SOM) characteristics on adjacent Cambisols in Eastern Germany. We investigated a continuous Norway spruce forest (F-F), a former cropland afforested in 1930 (C-F), and a grassland deforested in 1953 (F-G). For C and N stocks, we sampled the A and B horizons of nine soil pits per site. Additionally, we separated SOM fractions of A and B horizons by physical means from one central soil pit per pedon. To unravel differences of SOM composition, we analyzed SOM fractions by 13C-CPMAS NMR spectroscopy and radiocarbon analysis. For the mineral soils, differences in total C stocks between the sites were low (F-F∈=∈8.3 kg m-2; C-F∈=∈7.3 kg m-2; F-G∈=∈8.2 kg m-2). Larger total C stocks (+25%) were found under continuous forest compared with grassland, due to the C stored within the organic horizons. Due to a faster turnover, the contents of free particulate organic matter (POM) were lower under grassland. High alkyl C/O/N-alkyl C ratios of free POM fractions indicated higher decomposition stages under forest (1.16) in relation to former cropland (0.48) and grassland (0.33). Historic management, such as burning of tree residues, was still identifiable in the subsoils by the composition and 14C activity of occluded POM fractions. The high potential of longer lasting C sequestration within fractions of slower turnover was indicated by the larger amounts of claybound C per square meter found under continuous forest in contrast to grassland.
AB - Historic alterations in land use from forest to grassland and cropland to forest were used to determine impacts on carbon (C) stocks and distribution and soil organic matter (SOM) characteristics on adjacent Cambisols in Eastern Germany. We investigated a continuous Norway spruce forest (F-F), a former cropland afforested in 1930 (C-F), and a grassland deforested in 1953 (F-G). For C and N stocks, we sampled the A and B horizons of nine soil pits per site. Additionally, we separated SOM fractions of A and B horizons by physical means from one central soil pit per pedon. To unravel differences of SOM composition, we analyzed SOM fractions by 13C-CPMAS NMR spectroscopy and radiocarbon analysis. For the mineral soils, differences in total C stocks between the sites were low (F-F∈=∈8.3 kg m-2; C-F∈=∈7.3 kg m-2; F-G∈=∈8.2 kg m-2). Larger total C stocks (+25%) were found under continuous forest compared with grassland, due to the C stored within the organic horizons. Due to a faster turnover, the contents of free particulate organic matter (POM) were lower under grassland. High alkyl C/O/N-alkyl C ratios of free POM fractions indicated higher decomposition stages under forest (1.16) in relation to former cropland (0.48) and grassland (0.33). Historic management, such as burning of tree residues, was still identifiable in the subsoils by the composition and 14C activity of occluded POM fractions. The high potential of longer lasting C sequestration within fractions of slower turnover was indicated by the larger amounts of claybound C per square meter found under continuous forest in contrast to grassland.
KW - Black carbon
KW - C-CPMAS NMR
KW - Density fractionation
KW - Particulate organic matter
KW - Radiocarbon
UR - http://www.scopus.com/inward/record.url?scp=61349112717&partnerID=8YFLogxK
U2 - 10.1007/s00374-008-0336-9
DO - 10.1007/s00374-008-0336-9
M3 - Article
AN - SCOPUS:61349112717
SN - 0178-2762
VL - 45
SP - 347
EP - 359
JO - Biology and Fertility of Soils
JF - Biology and Fertility of Soils
IS - 4
ER -
