The roadless map of Greece
Scientific context In a biodiversity crisis era, land use change is the top threat for biodiversity decline, and road sprawl a key driver behind it globally. Roads cause direct habitat loss and fragmentation and a suite of negative environmental impacts (Ibisch et al. 2016). The dataset is developed for Greece, being less fragmented than the rest of Europe, but with higher rates of fragmentation increase. Description The dataset presents the roadless areas (RAs) of Greece (2/2020) in kmz format. RAs are defined as those land patches of a size greater than 1 sq.km that are at least 1 km away from the nearest road. Intersected by 367,370.74 km of roads, the Greek landscape is shattered in 4,659 patches (>1 km away from any road). The dataset presents the 1,115 RAs, accounting for 4.99% of the Greek land. This proportion is the Roadless Fragmentation Indicator (RFI), that can act as a straightforward finer scale indicator pinpointing areas of minimal anthropogenic pressures at more natural landscapes. The map includes high and medium confidence data. Red polygons indicate the RAs with an area ≥50 sq.km (high confidence data). They cover 0.51% of the Greek land and are located in six remote mountains: Lefka Ori, Timfi, Olympos, Taygetos, Saos, and Smolikas. Orange polygons indicate the RAs with an area 1-50 sq.km. Significance, use, limitations The database can be used: • to assess and monitor fragmentation in Greece in more natural ecosystems in terms of the RFI. Note the association with the SEBI 13 indicator (EEA 2012) • to pinpoint the remaining least disturbed natural areas that they should be legally protected as road-free zones supporting biodiversity conservation and ecosystem services. Note the suggested enlargement of the network of protected areas by the new European Biodiversity Strategy (EC 2020). • to guide spatial planning towards canalizing development projects, and related infrastructures in already developed and fragmented lands outside the larger RAs (e.g. sectors of renewable energy, tourism, transport etc) • to trigger policies towards landscape conservation and fragmentation minimization (CoE 2000; EC 2011). The database needs regular updating to be reliably used in conservation policy and in spatial planning for projects across various economic sectors. Funding This work was funded by the Green Fund of Greece References CoE 2000. https://www.coe.int/en/web/conventions/full-list/-/conventions/treaty/176 EC 2011. http://ec.europa.eu/science-environment-policy EC 2020. https://ec.europa.eu/info/files/communication-eu-biodiversity-strategy-2030-bringing-nature-back-our-lives_en EEA 2012. https://www.eea.europa.eu/publications/streamlining-european-biodiversity-indicators-2020 Ibisch et al. 2016. http://doi.org/10.1126/science.aaf7166
Steps to reproduce
We used the following freely available geospatial data: 1. OSM. Geofabrik GmbH and OpenStreetMap Contributors: Data/Maps http://download.geofabrik.de. Date of access: 11/2/2020 2. GEODATA. http://geodata.gov.gr. Date of access: 15/2/2020 3. MEE. Ministry of Environment and Energy. http://wfdgis.ypeka.gr. Date of access: 15/2/2020 Step 1: As a reference basis of the road network in Greece we used the freely available OSM database (1). We considered only those road classes that can be accessed by vehicles; road segments classified as footway, path, pedestrian or steps were excluded (total length of 16,511.78 km). The dataset included 352,486.39 km of roads. Step 2: We considered the Greek coastline (GEODATA-(2)) and we subtracted all waterbodies, including natural lakes, reservoirs and transitional water bodies, using the relevant database from the Ministry of Environment and Energy (MEE-(3)). The resulting land area of Greece was 130,223.86 sq.km. Step 3: We applied a buffer of 1 km from each side of the roads in the database and we excluded it from the database. We then calculated the area of the remaining polygons. Step 4: We inspected freely available imagery to identify and subsequently digitize any missing roads located in roadless fragments of an area equal or greater of 50 sq.km. Imagery included BingMaps (year 2013) and World Imagery (years 2015-2019) accessed via the ArcGIS online tool. A total of 14,884.35 km of road length was mapped. Step 5: We reapplied the 1 km buffer zone to the updated road network, and we excluded all land patches with an area less than 1 km sq.km. (3,544 fragments) to conclude to the 2020 roadless map of Greece.