Influence of Mediterranean shrublands management on soil carbon sequestration

This study evaluates how different management systems influence soil organic carbon (SOC) sequestration in a Mediterranean ecosystem of the Iberian Peninsula. SOC was quantified in 108 samples from wooded shrubland (WS) and shrubland without trees (S), featuring species such as Quercus rotundifolia, Phillyrea angustifolia, Retama sphaerocarpa, and Cistus ladanifer. SOC levels were significantly highest in WS (67.9 g/kg) than in S (37.4 g/kg), likely due to tree-shrub interactions that promote favorable carbon-storing microhabitats. Generalized additive mixed models identified normalized difference vegetation index (NDVI) and cation exchange capacity (CEC) as key SOC predictors (p = 0.015 and p < 0.001, respectively), with SOC increasing by 36.7% across the NDVI gradient and 178.4% across the CEC range. These results showed a positive correlation with vegetation biomass and soil fertility. Sustainable practices such as reforestation and organic amendments could boost sequestration and help mitigate climate change. Maintaining mixed tree-shrub cover is therefore vital for enhancing SOC in Mediterranean landscapes.