Landscape as a support for biodiversity: The arribas do Douro case study (international Douro natural park, NE Portugal)

Abstract

The fluvial canyon of the international Douro and Águeda rivers (NE Portugal-Spain border) supports a relevant natural and cultural heritage, which led to its recent integration in the portuguese conservation system – the International Douro Natural Park (IDNP). The spectacular steep cliffs, regionally named Arribas do Douro, are the major landscape feature of the region. They were developed during the incision of the Douro River and its tributaries on the Iberian Meseta, crosscutting granitic and metasedimentary terranes under the control of the fracture network. The landscape reflects the stream capture of the Tertiary Douro Basin towards the Atlantic by an active Quaternary down cutting. This geological setting provides one of the most important nesting habitat in Europe for vultures, eagles and black storks. The floristic heritage found on the rock slopes and ancient floodplains is also relevant. Evidence of the close relationship with the geological characteristics is also given by the millenary human occupation of the abrupt slopes, profiting from the microclimatic conditions for the production of wine, olive and almond. In conclusion, the Arribas do Douro landscapes have a relevant geological heritage and provide the support for the IDNP biodiversity. Therefore, the nature conservation policies must take this strong linkage into account.