Abstract Background Obscured by the more prevalent discussion of intensification and expansion of agricultural land, the impacts of the abandonment of many grasslands and croplands of the world in recent decades have received limited attention in the literature. Land abandonment is a common phenomenon in the Mediterranean Basin, a global biodiversity hotspot, but little is known about the impacts of this process on biodiversity. To upscale existing case-study insight to a Pan-Mediterranean level, we plan to perform a systematic review of the effects of land abandonment on plant and animal richness and abundance in pastures, arable lands and permanent crops of the Mediterranean Basin. In particular, we ask (1) which taxonomic groups are most affected by land abandonment; (2) whether different spatial and temporal scales of studies influence species richness and abundance outcomes; (3) whether previous land use and current anthropogenic impacts on abandoned lands determine differences in the number and abundance of species; and (4) whether landscape context modifies the impacts. Methods Our review will be based on searching scientific databases as well as the internet for empirical studies on the effects of land abandonment on biodiversity in the Mediterranean Basin. Study selection follows a three-stage process and includes study quality assessment. Extracted data will be synthesized through meta-analysis. Results will be presented in the form of a quantitative (e.g. figures indicating effect sizes, tables summarizing heterogeneity statistics) and narrative synthesis. Additional aspects will be addressed through meta-regression and sub-group analyses.

Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a meta-analysis of the effects of land abandonment on plant and animal species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1) which taxonomic groups (arthropods, birds, lichen, vascular plants) are more affected by land abandonment; (2) at which spatial and temporal scales the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size  = 0.2109, P<0.0001) plant and animal species richness and abundance overall, though results were heterogeneous, with differences in effect size between taxa, spatial-temporal scales, land uses, landforms, and climate. In conclusion, there is no "one-size-fits-all" conservation approach that applies to the diverse contexts of land abandonment in the Mediterranean Basin. Instead, conservation policies should strive to increase awareness of this heterogeneity and the potential trade-offs after abandonment. The strong role of factors at the farm and landscape scales that was revealed by the analysis indicates that purposeful management at these scales can have a powerful impact on biodiversity.

Wildfires are increasing in severity, and magnitude in the Mediterranean Basin in recent years, reaching a yearly average of 450 000 ha over the last decade. Drivers include climate change, land-use change, and land abandonment. Wildfire mitigation requires landscape-level action as impact to each parcel is affected by the conditions of the others. We conducted a case study of a regional-level initiative that develops community efforts to mitigate wildfires through silvo-pastoral agroforestry systems, using an integrated landscape management approach. This approach involves collaboration among stakeholders to achieve multiple objectives. In order to derive insights into its potential, we asked participating land managers: (1) What motivates their participation?, (2) How do they perceive initiative outcomes?, and as urban outmigrants with non-traditional goals are increasing in rural areas, (3) Do responses differ between rural and neo-rural participants? Our results show that managers feel highly affected by wildfires and are strongly motivated to reduce wildfire risk. Land abandonment and inappropriate policy were major concerns. The initiative was seen to have positive outcomes for individual participants as well as the region, and to stimulate community connectedness. We conclude that fit to local contexts, integrated landscape management can be a well-received approach to reducing wildfire risk. Agroforestry systems in Extremadura can act as "productive fuelbreaks" that reduce fire risk over extensive areas, while restoring traditional landscapes. We suggest that programs to reduce wildfire risk can also be used as a leverage point for financing rural revival and provision of multiple ecosystem services.

Supplementary information

The online version contains supplementary material available at 10.1007/s10457-022-00771-6.