Does sward management affect carbon storage under upland permanent pasture?

Soil is the largest terrestrial sink for atmospheric carbon. In the UK, almost a third of soil organic carbon (SOC) is found in the uplands. Research in the uplands has focused on peat as a carbon sink. Other research has explored changes between land use types, such as pasture, forestry and arable systems. Management within a land-use type, for example, which has an effect on carbon storage in grasslands, is less well understood. Using the Brignant plots, established in 1994 to explore the legacy of low intensity management in upland pastures, soil organic carbon (SOC) was estimated using an equivalent soil mass (ESM) methodology. Because it does not rely on fixed depths, the ESM method can be useful to calculate SOC in soils where sampling to a fixed depth is difficult when impeded by rocky, thin soil, or other obstacles, making it useful at Brignant where soil depth is variable and very stony. Management treatments are: grazing only, hay-cutting only and hay-cutting with aftermath grazing; all with and without liming. A grazed control treatment which has N, P, K and lime added as per industry best practice runs alongside. This study describes the use of ESM to determine SOC levels between a range of management options in an upland fringe-pasture setting