Long-term bio-cultural heritage: exploring the intermediate disturbance hypothesis in agro-ecological landscapes (Mallorca, c. 1850-2012)

Abstract

We applied an intermediate disturbance-complexity approach to the land-use change of cultural landscapes in the island of Mallorca from c. 1850 to the present, which accounts for the joint behaviour of human appropriation of photosynthetic capacity used as a measure of disturbance, and a selection of land metrics at different spatial scales that account for ecological functionality as a proxy of biodiversity. We also delved deeper into local land-use changes in order to identify the main socioeconomic drivers and ruling agencies at stake. A second degree polynomial regression was obtained linking socio-metabolic disturbance and landscape ecological functioning (jointly assessing landscape patterns and processes). The results confirm our intermediate disturbance-complexity hypothesis by showing a hump-shaped relationship where the highest level of landscape complexity (heterogeneity connectivity) is attained when disturbance peaks at 50 60 %. The study proves the usefulness of transferring the concept of intermediate disturbance to Mediterranean cultural landscapes, and suggests that the conservation of heterogeneous and well connected land-use mosaics with a positive interplay between intermediate level of farming disturbances and land-cover complexity endowed with a rich bio-cultural heritage will preserve a wildlife-friendly agro-ecological matrix that is likely to house high biodiversity.