Variation in organic‐carbon concentration and bulk density in Flemish grassland soils

Abstract

The different management regimes on grassland soils were examined to determine the possibilities for improved and/or changed land management of grasslands in Flanders (Belgium), with respect to article 3.4 of the Kyoto Protocol. Grassland soils were sampled for soil organic carbon (SOC) and for bulk density.For all grasslands under agricultural use, grazing and mowing + grazing led to higher SOC stocks compared with mowing, and grazing had higher SOC stocks compared with mowing + grazing. Overall, 15.1 ± 4.9 kg OC m–2 for the clayey texture, 9.8 ± 3.0 kg OC m–2 for the silty texture, and 11.8 ± 3.8 kg OC m–2 for the sandy texture were found for grassland under agricultural use to a depth of 60 cm. For seminatural grasslands, different results were found. For both the clayey and silty texture, mowing and mowing + grazing led to higher SOC stocks compared with grazing. The clayey texture had a mean stock of 15.1 ± 6.6, the silty texture of 10.9 ± 3.0, and the sandy texture of 12.1 ± 3.9 kg OC m–2 (0–60 cm). Lower bulk densities were found under grazed agricultural grassland compared with mown grassland but for seminatural grassland, no clear trends for the bulk density were found. The best management option for maintaining or enhancing SOC stocks in agricultural grassland soils may be permanent grazed grassland. For seminatural grassland, no clear conclusions could be made. The water status of the sampled mown fields was influencing the results for the clayey texture.Overall, the mean SOC stock was decreasing in the order clay > sand > silt. The higher mean SOC concentrations found for the sandy texture, compared to the finer silty texture, may be explained by the historical land use of these soils.

Soil organic carbon contents of agricultural land in the Netherlands between 1984 and 2004

“…Exchange of land between arable farms and grassland-based dairy farms has increase during the last decades. Decreasing SOC content in grassland soils in Belgium was also related to changes in land use (Mestdagh et al, 2004(Mestdagh et al, , 2006.…”

“…So far, most estimates are either derived from long-term field experiments (e.g., Jenkinson and Rayner, 1977;Wadman and De Haan, 1997) and/or simulation modelling (Jenkinson et al, 1987;Jenkinson, 1988;Yang and Janssen, 2000;Vleeshouwers and Verhagen, 2002;Freibauer et al, 2004;Vellinga et al, 2004;Smith et al, 2005). Few studies have used repeated inventories for estimating changes in SOC at regional scales (Sleutel et al, 2003;Lettens et al, 2004;Bellamy et al, 2005;Mestdagh et al, 2006). Some recent studies suggest that SOC of European agricultural land is decreasing (Vleeshouwers and Verhagen, 2002;Sleutel et al, 2003;Bellamy et al, 2005).…”

Spatial and vertical variation of soil carbon at two grassland sites — Implications for measuring soil carbon stocks

“…Land use history and productivity at Kaltenborn were comparable to Mehrstedt and the profiles of SOC concentrations and stocks had a very similar form, but at different concentration levels. In Flemish seminatural and intensively managed grassland soils, SOC stocks increased from sandy to clayey soil (Mestdagh et al, 2006). In this study of extensively grazed grassland, the soils with clay texture contained on average 123t C ha − 1 ± 3.9 for 0-60cm depth (mean ± s.d.).…”

What Global and/or European Agriculture Will Need from Grasslands and Grassland Breeding over the Next 10–15 Years for a Sustainable Agriculture

“…Although temporary grassland is a better carbon sink than arable land, it stores about 50 % less carbon than permanent grassland and cut grassland stores about 50 % less carbon than grazed grassland (Mestdagh et al 2004;Conijn 2007;Vertès et al 2007), since a proper cutting management allows less senescent material to return to the soil.…”