Influence of soil texture, moisture regime and land use on carbon storage in Belgian soils

Human activities significantly altered the carbon cycle on earth and gave rise to elevated atmospheric CO2 concentrations. In order to decrease atmospheric CO2 concentrations, carbon storage in soil is considered as a possible option in the Kyoto-protocol. In the present study, the influence of soil texture, soil moisture regime and land use on the storage of soil organic matter (SOM) was investigated. The results were used to formulate management strategies that will increase soil organic matter content. In the present study, a multiple regression analysis was performed on data of 8990 soil profiles from the AARDEWERK database. From the studied dataset, only soils from the northern part of Belgium (above the Samber and Meuse rivers) showed a significant relationship between soil texture, soil moisture regime, land use and SOM-content. However, only a part of the variability in SOM-content could be explained by soil texture, soil moisture regime and land use (r² = 0.212). A high SOM-content was preferentially found in wet meadows with a clayey soil texture. However, the influence of soil texture is prone to interaction-effects with the two other variables (moisture regime and land use). Although soils with a clayey texture contain more SOM than sandy and loamy soils, Anthrosols in the Campine region are an exception since these sandy soils are characterized by an elevated SOM content Possible management options that can increase or stabilize carbon storage in soils consist of surface drainage, irrigation, limited soil cultivation, reforestation and a shift in land use from field to meadow. Although no ‘ultimate’ solution can be proposed, the combination of different modest strategies that are also economically efficient can contribute to the increased sequestration of carbon in soils. As such, the storage of carbon in soil can be considered as a feasible management option to reduce atmospheric CO2 concentrations.status: publishe