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Land abandonment in the Mediterranean mountains since the 20th century has led to a reduction of ecosystem services, due to revegetation and homogenization of the landscape. To counteract these effects, the regional administration of La Rioja in Spain initiated a Plan for Shrub Clearing (PSC) combined with extensive livestock grazing in 1986, which is still in action today. This study analyses the effects of pairing clearing with grazing in an experimental area of the Leza valley (Iberian System) on: (i) the landscape structure and structural diversity; (ii) the production of pasture; (iii) fire control; (iv) soil organic carbon sequestration (also considering soil environmental types); (v) surface water resources. The results show that: (i) a more fragmented landscape with greater diversity is created; (ii) grazing land is almost doubled in alkaline soils and four-fold in siliceous soils; (iii) fires are considerably reduced, with the mean surface fire spread falling from 34.1 ha/year from 1968 to 1985, to 1.2 ha/year between 1986 and 2022; (iv) regenerated post-clearance grazing soils sequester more organic carbon than that of shrublands, especially older clearings on alkaline soils (55.3 % more); (v) clearing increases hydrological connectivity and water resources. The conclusion is that managing the Mediterranean mid-mountains could be a very effective strategy to improve the supply of certain ecosystem services and improve the current socio-economic perspective of these marginal areas in a context of Global Change. The PSC also contributes to local development by increasing livestock numbers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Semiarid climate conditions hamper natural re-vegetation, leaving the soil vulnerable to erosion after the cessation of agriculture. Therefore, soil and landscape protective measures, especially afforestations, have been implemented in the Mediterranean region since the early 20th century. This study aims to determine the long term impact of afforestation on soil functioning, in comparison with natural re-vegetation (secondary succession) on abandoned fields and semi-natural vegetation. A comparison of secondary succession and afforestation with the present traditional rain fed cereal fields and semi-natural (open) forest, including natural resource islands, was made as well. Composite soil samples were taken to study the physical (i.e. texture, aggregate stability) and chemical (i.e. carbon content, nutrient availability) soil characteristics after 20 and 40 years of afforestation and secondary natural succession. To take into account the resource island effect, the spatial heterogeneity induced by differences in plant cover, samples were taken both below and in between the tree canopy of the semi-natural and afforested Pinus halepensis trees. Our results indicate that under secondary succession on abandoned fields, soil quality improves non-linearly and only marginally over a time of 40 years. The afforestation showed a much more pronounced linear increase for most soil quality indicators, resulting in soil conditions comparable to what can be found under the semi-natural forest vegetation. Site preparation might have been a crucial factor for the success of ecosystem restoration in the studied dry land area as it improved water availability for the afforestation., (Copyright © 2018 Elsevier B.V. All rights reserved.)