Classification of linear environmental impacts and habitat fragmentation by object-oriented analysis of aerial photographs in corrubedo national park (NW Iberian Peninsula)

Abstract

The increase of tourism in coastal protected areas is a potential driver for ecosystem fragmentation, as it frequently involves damages to their biodiversity values. One of the key issues in the management of protected areas is their access regulation in order to avoid negative effects of trampling on natural and semi-natural habitats. Protection measures need to be carefully designed to achieve an effective protection of biodiversity while minimizing as possible the constraints to tourism development. The accurate design and monitoring of performance of such measures needs effective methods to evaluate fragmentation. In this work, we aimed at the development of a consistent method for the automatic recognition of linear environmental impacts (paths and tracks) on natural and semi-natural habitats using colour aerial photo- graphs. The method is based on a multi-scale segmentation of the images. Brightness, shape and connectivity criteria were implemented at several scales of analysis by means of a fuzzy knowledge base, allowing the recognition of linear elements corresponding to networks of trails. We used as study case a protected area in the NW coast of the Iberian Peninsula with a complex vegetation pattern. The method allowed the general discrimination of linear artificial features, causing environmental impacts and human- driven habitat fragmentation, against other linear elements with similar brightness and shape, but different thematic meaning regarding their conservation implications.