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

Abstract

Abstract Context The 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. Objectives We 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. Methods Aerial 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. Results The 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. Conclusion The 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.