Abstract
Managing carbon storage at the landscape level through emission reduction and carbon sequestration is emerging as a viable local response to atmospheric carbon loading from anthropogenic activities. The conversion of uncultivated land uses and land covers (LULCs) to arable or perennial cropping systems is widely recognized as resulting in significant decomposition of soil organic carbon (SOC). Minimizing conversion and advocating alternative management of these cultivated land uses have been identified as having the potential to minimize this loss and potentially sequester atmospheric carbon. However, effective landscape management requires a more rigorous understanding to inform local decision-making. This review of published studies within diverse Mediterranean landscapes found that cultivated areas contained roughly half of the SOC of uncultivated LULCs, with vineyards often containing the lowest observed SOC levels in a landscape. Mitigation through alternative management can result in higher SOC levels than conventional management, but the latter is likely to be a fraction of the C loss from initial cultivation. However, the majority of relevant studies relied on shallow standardized sampling depths and other protocols that have been demonstrated to lead to miscalculations of existing SOC stocks. Novel sampling techniques and emerging research opportunities have the potential to revolutionize our understanding of this question and support scientifically sound carbon-based landscape management.