Effect of protected areas in reducing land development across geographic and climate conditions of a rapidly developing country, Spain

Protected areas (PAs) aim at safeguarding biodiversity and ecosystem services in the long term. Despite the remarkable growth in area covered by PAs in recent years, biodiversity trends continue to worsen as a result of serious global pressures such as habitat destruction and degradation. One main cause of habitat destruction and degradation is land development that implies the replacement of natural land uses-land covers (LULCs) with artificial ones. Here, we assessed the effectiveness of four PA networks at preventing land development in Spain, a biodiversity-rich country that has experienced recent rapid environmental transformations, using two models of increased validity: an original model and a biophysically enhanced model. We applied a before-after control-impact (BACI) design whereby absolute artificial area increase (AAI) and relative artificial area increase (RAI) were compared across PA categories (nature reserves [NRs], nature parks [NPs], Sites of Community Importance [SCIs], and Special Protection Areas [SPAs]), study zones (coastal and inland), and climates (Atlantic and Mediterranean) using CORINE Land Cover (CLC) data and two control zones: 1- and 5-km buffers around protected polygons. NRs prevented land development, whereas other categories reduced it moderately to very substantially in the assessed period. AAI was especially intense in inland SPAs and NPs. NRs and NPs were the most effective PA categories inland, whereas NRs and SPAs were the most effective ones on the coast. Land development was greater on the Spanish coast than inland inside and outside PAs, especially around Macaronesian and Mediterranean PAs. Atlantic PAs experienced similar or greater land development values than surrounding areas. Our results are intended to guide future conservation efforts in Spain, chiefly on its heavily pressured coastal environment.