From the local landscape organization to land abandonment: an analysis of landscape changes (1956-2017) in the Aisa Valley (Spanish Pyrenees)

ContextThe Mediterranean mountains have witnessed the revegetation of former pasture and cultivated fields since the mid-20th century. The process started when the mountains joined a dynamic and competitive market, which led to depopulation, abandoning cultivated fields, and a reduction in extensive livestock farming.ObjectivesWe investigate changes in land use and land cover (LULC) and landscape structure in a valley of the Central Pyrenees in 1956, 1981 and 2017, and we discuss the implications for land management within a multidisciplinary context.MethodsAerial photographs are used to map the LULC in 1956, 1981 and 2017, followed by landscape ecology metrics and indices to analyse the structure of the landscape.ResultsThe results show: (i) a reduction in cultivated area (-42%) and pastures (-63%) in the montane belt between 1956 and 2017, while forests doubled in area; (ii) changes in LULC are more significant in the montane belt than in subalpine and alpine areas; (iii) based on the Kappa index, it was found that the 29% of the area had undergone changes in LULC between 1956 and 2017, with the changes being greater in the first period (1956-1981) than in the second (1981-2017); (iv) the structure and heterogeneity of the landscape shows an increase between 1956 and 1981, and a change in trend from 1981 to 2017, so that the landscape is more homogeneous in 2017 than in 1956.ConclusionThe discussion suggests the need to maintain and recover mosaic landscapes, since their structure is akin to traditional cultural ones, to increase biodiversity and sustainability, and provide ecosystem services to the population.

Automated summary

Since the mid-20th century, the Mediterranean mountains have witnessed the revegetation of former pasture and cultivated fields. This study examines the changes in land use and land cover in a valley of the Central Pyrenees from 1956 to 2017, revealing a decrease in cultivated and pasture areas and an increase in forest area. The findings emphasize the importance of preserving and restoring mosaic landscapes for biodiversity, sustainability, and ecosystem services.