Estimating soil carbon sequestration potential in Portuguese agricultural soils through land-management and land-use changes: a tier 1 approach

Mariana Luís Raposo

Key information

Authors:

Mariana Luís Raposo (Mariana Luís Raposo)

Supervisors:

Tiago Morais Delgado Domingos (Tiago Morais Delgado Domingos); Paulo José Tavares Canaveira (Paulo José Tavares Canaveira)

Published in

12/19/2023

Abstract

It is widely accepted that, in order to limit global warming to 2ºC and to pursue efforts to stay below 1,5ºC, it is necessary to employ negative emission technologies (NETs). Soil carbon sequestration (SCS) is a NET with low energy and cost requirements with a potential to both contribute to climate change mitigation and promote adaptation of agricultural systems. For cropland and grassland soils, SCS can be achieved through adequate land-use and land management practices such as improved crop varieties, reduced tillage and no-till, conversion to irrigation and improved grasslands. The CAP (Common Agricultural Policy) promotes agri-environmental measures and eco-schemes that reflect the growing concern of European policymakers in mitigating climate change, hence, the ability to measure, communicate and verify the effect of such agricultural practices on European soil becomes pressing. This M.Sc. dissertation aims to be a preliminary study towards understanding how the CAP agri-environmental measures and eco-schemes influence SCS. Following IPCC’s Tier 1 methodology, we provide: 1) estimates on the current SOC (soil organic carbon) content in mainland Portugal’s agricultural soils; 2) sequestration/emission potentials which result from specific land management practices and land-use changes (transitions); and 3) estimates for the total national sequestration potential for each transition.