Options for climate change mitigation in agricultural soils and impact on crop and grassland production: a multi-scale study

The decline of soil fertility is recognized by the European Union (EU) as the cause of yields reduction in many arable lands. The Soil Thematic Strategy proposed by the European Commission in 2006, identified the decline of organic matter as one of the main soil threats in EU. Organic carbon content is a recognised indicator of soil quality. Several studies have investigated this relationship through long-term field level experiments. This thesis presents a different approach: starting from data and information at EU level, a regional case study is investigated. The general objective of this thesis is to evaluate and quantify the impact of specific management practices in preserving or sequestering soil organic carbon in EU and regionally. The thesis is structured in five chapters: the first is a general introduction on the need for preserving soil organic carbon in the agricultural land and a review on the relevant legislation at international and European level. The second is a scoping chapter that presents a comparison on the available data on organic carbon content at EU level. The third chapter is a meta-analysis on soil organic carbon sequestration data available in scientific literature and reflection the management practices applied at EU scale. In the fourth chapter, the CENTURY model is applied at regional level in order to estimate the actual values of soil organic carbon stock and to model the implementation of the most promising management practices in two different climatic scenarios. The last chapter outlines the general conclusions and recommendations.