The Loss of Landscape Ecological Functionality in the Barcelona Province (1956–2009): Could Land-Use History Involve a Legacy for Current Biodiversity?

Enric Tello,Claudio Cattaneo,Roc Padró,Joan Marull,Francesc Coll

doi:10.3390/su12062238

Abstract

Could past land uses, and the land cover changes carried out, affect the current landscape capacity to maintain biodiversity? If so, knowledge of historical landscapes and their socio-ecological transitions would be useful for sustainable land use planning. We constructed a GIS dataset in 10 × 10 km UTM cells of the province of Barcelona (Catalonia, Spain) for 1956 and 2009 with the changing levels of farming disturbance exerted through the human appropriation of photosynthetic net primary production (HANPP), and a set of landscape ecology metrics to assess the impacts of the corresponding land-use changes. Then, we correlated them with the spatial distribution of total species richness (including vascular plants, amphibians, reptiles, birds and mammals). The results allow us to characterize the main trends in changing landscape patterns and processes, and explore whether a land-use legacy of many complex agroforest mosaics maintained by the intermediate farming disturbance managed in 1956 could still exist, despite the decrease or disappearance of those mosaics before 2009 due to the combined impacts of agroindustrial intensification (meaning higher HANPP levels), forest transition (meaning lower HANPP levels) and urban sprawl. Statistical analysis reveals a positive impact of the number of larger, less disturbed forest patches, where many protected natural sites have been created in 1956–2009. However, it also confirms that this result has not only been driven by conservation policies and that the distribution of species richness is currently correlated with the maintenance of intermediate levels of HANPP. This suggests that both land-sharing and land-sparing approaches to biodiversity conservation may have played a synergistic role owing to the legacy of complex land cover mosaics of former agricultural landscapes that are now under a serious threat.

Highlights

Europe has experienced a long-lasting and widespread forest transition on the steep terrain [1,2,3,4,5], whereas urban-industrial facilities and linear infrastructures are taking ever more land on the plains
We constructed a GIS dataset in 10 × 10 km UTM cells of the province of Barcelona (Catalonia, Spain) for 1956 and 2009 with the changing levels of farming disturbance exerted through the human appropriation of photosynthetic net primary production (HANPP), and a set of landscape ecology metrics to assess the impacts of the corresponding land-use changes
After constructing a GIS dataset to assess from a landscape ecology point of view the main land use and cover change (LUCC) in 48 UTM cells of 10 × 10 km in the Barcelona province from 1956 to 2009, we obtained two relevant set of statistical results by testing to what extent the spatial distribution of total species richness currently observed correlates with the changes experienced from 1956 to 2009 in the levels of farming disturbance (HANPP), land cover equi-diversity (H’), grain size (LPI), fragmentation (EMS), ecotony (PD, Edge density (ED)), and ecological connectivity (ECI)

Summary

Introduction

Europe has experienced a long-lasting and widespread forest transition on the steep terrain [1,2,3,4,5], whereas urban-industrial facilities and linear infrastructures are taking ever more land on the plains. There are authors who praise this forest transition for some of its environmental benefits, such as carbon sequestration and lower human pressure over large mountain areas where species richness can refuge [8,9,10], while others have raised concerns about other negative impacts on biodiversity [11,12,13,14,15]. These contrasting views on forest transition are tightly linked to the ongoing debate between the “land sparing” and “land sharing” approaches to biological conservation [16]. According to the intermediate disturbance hypothesis, landscape heterogeneity can contribute to a dynamic biodiversity peak at intermediate levels of ecological disturbance, through the interaction among land cover diversity, ecosystem complexity, and dispersal abilities of the colonizing species that escape form the most disturbed patches and are sheltered in less disturbed ones [16,21,22,23,24,25]

Results

Discussion

Conclusion