Indicator: Natural area connectivity on land
Indicator name

Tag: None
Indicator abbreviated name

Definition: Average proportion of connected natural area on land within a local neighbourhood of approximately 50 km2 at EU27 level. Both average connectivity within the natural area of the EU27 countries (FAD) and average connectivity within the overall area of the EU27 countries (AVCON) are reported.
Definition describing what the indicator measures

Unit: % of connected natural area on land
Measurement unit of the indicator values

Spatial coverage: EU (current composition, only continental areas and Macaronesia)
Geographic area covered by the indicator

Temporal coverage: 2016-2022
Time coverage of the indicator from first to most recent available year

Update frequency: Every 2 years
Frequency at which indicator is updated

DPSIR: State
DPSIR classification framework: Driver, Pressure, State, Impact, or Response

Method: 1) Land cover classes of the input ESA-CCI Land cover map are reclassified into two categories: natural area and non-natural area. Among the 37 classes of ESA-CCI Land cover map, the following classes are considered as non-natural: Cropland, rainfed (herbaceous, tree or shrub cover), Cropland, irrigated or post-flooding, Mosaic cropland (>50%) / natural vegetation (tree, shrub, herbaceous cover) (<50%), Grassland, Urban areas. 2) The reclassified dataset is then submitted to the Foreground Area Density (FAD) analysis, performed using GWB (GuidosToolbox Workbench): for each pixel classified as natural area, the relative number of connected pixels also classified as natural areas in its local neighbourhood of 23 x 23 pixels, equivalent to approximately 50 km2, is calculated. Specifically, for each pixel, the FAD value is computed as: FAD = Number of pixels classified as natural areas / Total number of pixels in kernel 3) The output map from FAD analysis is then intersected with administrative boundaries (source: FAO GAUL, revision 2015). 4) Zonal statistics are computed by country as well as at EU27 level, and the average FAD and AVCON values for each country and for EU27 are retained. AVCON value is derived from average FAD as: AVCON = average FAD x natural area percentage.
Description of the main methodological steps used to calculate the indicator

Reference: https://nsojournals.onlinelibrary.wiley.com/doi/full/10.1111/ecog.05864 (accessed on 26/06/2025). Robuchon, M., Liquete, C., Neuville, A., Delli, G., Gkimtsas, G., Goutis, D., Mahmoud, I., Vogt, P., Borg, J. and Hagyo, A., State of play and future steps for the EU Biodiversity Strategy (EU BDS) dashboard, European Commission, Ispra, 2024, JRC137635.
Reference sources describing the indicator and method to calculate it (e.g. peer-reviewed articles, scientific/technical reports, webpages, other)

Producer: Joint Research Centre
Institution which produces the calculation of the indicator values

Provider: Joint Research Centre
Institution supplying the indicator values, even if not the original producer of indicator values

Open source: True
Indicates whether calculation code is openly available

Spatial scope (Member States): True
Whether the indicator is available at Member States level

Spatial scope (EU27): True
Whether the indicator is available at EU27 aggregated level

Spatial scope (global): False
Whether the indicator is available at global level

Accuracy uncertainties: The spatial resolution (300m) of the input dataset used do not allow to take into account small-scale natural areas. Furthermore, the indicator is based on a reclassification of land cover classes into a binary classification (natural and non-natural areas), and therefore (i) it does not capture the actual naturalness gradient of land areas and (ii) it represents overall connectivity of natural land, without distinguishing connectivity within each land cover class of natural land.
Comment on data accuracy, limitations, and uncertainty

Comments: None
Additional remarks

Storage

Copyright/Licence of use: None
Copyright or licensing information related to the indicator