The objective of this presentation is to develop metrics to measure the connectivity of habitats and small landscape elements for various reference units such as administrative boundaries (municipalities, counties) and natural spatial units or a regular grid (INSPIRE Grid). For the habitat types ‘wet habitats’, ‘wood-dominated areas or forests’ and ‘dry habitats’, we examined connectivity with the inclusion of small-scale landscape elements. Thereby, we measure on different administrative levels, whereby habitats lying on borders are considered as a whole. Furthermore, the focus is on the implementation of barriers that are impossible or difficult for animals to cross, such as roads, rivers, or train tracks.

Two measurement concepts used in the City Biodiversity Index (Chan et al., 2021, p. 15) and the Proximity Index (Gustafson, Parker, 1992) are compared and expanded accordingly. The City Biodiversity Index (CBI) is a set of 28 indicators, including the two indicators 'Proportion of Natural Areas' and 'Connectivity Measures for Ecological Networks', the latter measuring the connectivity of ecological networks in cities. The Proximity Index is a measure of the proximity and size of neighboring elements and is described by four variants (PX92, PXpt, PXfg and PX94). With the Proximity Index, it is possible to integrate movement barriers into the evaluation algorithm, so that the interruptions of the habitat networks by roads etc. were taken into account, as is already the case with ‘Connectivity Measures for Ecological Networks’. The transferability to the spatial reference units can be achieved by means of spatial aggregation, so that larger habitats that extend across regional boundaries were also adequately taken into account. In the results for the CBI, it was found that the two indicators examined should always be viewed in conjunction. It has been shown that paying attention to barriers significantly influences the results. Overall, the values aggregated into levels (grid or administrative units) lead to results that are comprehensible and clearly presentable as maps and statistical measures. In summary, we are convinced that the selected indicators, taking barriers into account, can be used for regular monitoring of the environmental status of the landscape even in larger areas and can thus be an important basis for spatial planning and success evaluation.