Carbon losses from soil and its consequences for land-use management.

This paper reviews our current knowledge and understanding of carbon processes in the terrestrial ecosystem with a view to reducing soil carbon losses by optimising land-use and land management. Processes that influence the fate of carbon (in both terms of quantity and quality) are important in determining soil fertility, quality and health as well as consequences for future environmental change scenarios. We need to understand the processes that determine soil carbon losses and the fate of the carbon once lost from the soil in order to provide sustainable solutions for mitigating these carbon losses as part of land management "best practice" and balancing national carbon budgets. Here we review the amount of carbon within the UK terrestrial pool, the processes involved and factors influencing carbon transport to and from soils, the fate of the carbon once it has been lost from the soil environment and land-use scenarios that affect carbon losses. We conclude with possible management options to reduce soil carbon loss and identify gaps in knowledge in order to better understand carbon processes in the terrestrial environment.