UK-3 :: Soil ‘Regeneration’

It is widely claimed that an increase of soil organic matter (SOM) by 20% would be beneficial but how much this is needed is contested. Research is being carried out at Rothamsted & Lancaster University in this area. However a lot of resources and money could be committed without understanding what will be delivered. The origin of the 20% figure is unclear.
How to increase to Soil Organic Matter in poorer soils, and what level is achievable, desirable, beneficial? Sharing lessons in best practice, costs & benefits in peatland restoration would be valuable.
Specific research questions (following the conceptual model of INSPIRATION)
Demand By restoring local soil, the need to exploit and perhaps consume soil elsewhere is reduced. The amount of soil restored is likely to be a fraction of any soil conserved elsewhere giving a synergistic return on soil restoration investment.
Natural capital Soil is a limited, quasi-non-renewable resource and improving its fertility and ability to act as a physical and chemical buffer will enhance natural capital. To what level should soil organic matter be increased?
Land management Improved soil would yield enhanced ecosystem services, including yields, and hence reduce demands on land elsewhere. How should soil organic matter content be increased?
Net impacts Improved soil would be able to offer enhanced ecosystem services and locally to the point of demand.
Justification The requested research would deliver a better evidence base for specific policy targets on soil organic matter content.