Towards an energy–landscape integrated analysis? Exploring the links between socio-metabolic disturbance and landscape ecology performance (Mallorca, Spain, 1956–2011)

Abstract

The role of agricultural landscapes in biodiversity conservation is an emerging topic in a world experiencing a worrying decrease of species richness. Farm systems may either decrease or increase biological diversity, depending on land-use intensities and management. We present an intermediate disturbance-complexity model (IDC) of cultural landscapes aimed at assessing how different levels of anthropogenic disturbance on ecosystems affect the capacity to host biodiversity depending on the land matrix heterogeneity. It is applied to the Mallorca Island, amidst the Mediterranean biodiversity hotspot. The model uses the disturbance exerted when farmers alter the Net Primary Production through land-use change as well as when they remove a share of it (HANPP), together with Shannon–Wiener index (H′) of land-cover diversity. The model is tested with a twofold-scalar experimental design (1:50,000 and 1:5000) of a set of landscape units along three time points (1956, 1989, 2011). Species richness of breeding and wintering birds, taken as a biodiversity proxy, is used in an exploratory factor analysis. The results clearly show that when intermediate levels of HANPP are performed within intermediate levels of complexity (H′) in landscape patterns, like agro-forest mosaics, great bird species richness and high socio-ecological resilience can be maintained. Yet, these complex-heterogeneous landscapes are currently vanishing due to industrial farm intensification, rural abandonment and urban sprawl. The results make apparent the usefulness of transferring the concept of intermediate disturbance-complexity interplay to cultural landscapes. Our spatial-explicit IDC model can be used as a tool for strategic environmental assessment of land-use planning.