Zone di appoggio

Biodiversityv00.50 credits/per_km2

Responsible:Niccolò Calandri

Stepping Zones

Overview

Stepping zones (or "stepping stones") are small, isolated natural or semi-natural areas that facilitate wildlife movement between larger habitat patches across fragmented landscapes. Unlike continuous ecological corridors, stepping zones function as discrete refugia that species can use sequentially during dispersal.

Examples include:

Isolated natural areas (forest remnants, hedgerows)
Tree-lined roads (avenues, riparian buffers)
Temporary wetlands (seasonal ponds, flooded fields)
Urban parks and gardens (green spaces within built-up areas)

Stepping zones are particularly important for:

Birds and flying insects that can traverse gaps between habitat patches
Plant species whose seeds are dispersed by wind or animals over moderate distances
Urban biodiversity where continuous corridors are impossible due to built infrastructure

The data is stored as vector geometries in the internal database (protected_areas table with source='stepping_zones').

Calculation Methodology

Identification approach:

Stepping zones are identified through ecological connectivity analysis:

Habitat patch mapping — Protected areas (WDPA, KBA, Natura 2000) and natural land cover patches are mapped as source/destination nodes
Gap analysis — Areas between patches that exceed corridor width thresholds but contain small natural elements are identified
Stepping zone classification — Small habitat patches (< threshold size) within connectivity gaps are classified as stepping zones
Connectivity contribution — Each stepping zone's contribution to overall landscape connectivity is assessed using graph-theoretic metrics

Data Sources

Source	Provider	Type	Storage
Ecological connectivity analysis	Internal	Vector polygons	`protected_areas` table (source='stepping_zones')

Technical Notes

Stepping zones are complementary to ecological corridors; together they form the connectivity component of green infrastructure
The effectiveness of stepping zones depends on species-specific dispersal capabilities
Urban stepping zones are particularly important in highly fragmented landscapes
Regular updates incorporate new green space designations and land cover changes

References

Saura, S., Bodin, Ö., Fortin, M.J. (2014). "Stepping stones are crucial for species' long-distance dispersal and range expansion through habitat networks". Journal of Applied Ecology, 51(1), pp. 171–182.
Baum, K.A., Haynes, K.J., Dillemuth, F.P., Cronin, J.T. (2004). "The matrix enhances the effectiveness of corridors and stepping stones". Ecology, 85(10), pp. 2671–2676.

Data Sources & References

Sources

WRD_WDPAX_25WRD_KBAXX_25EUR_N2KXX_25CAN_CPCAD_23USA_PADXX_25

Methodology

Le stepping zones (zone di passaggio) vengono estratte dal database interno (tabella protected_areas con source='stepping_zones'), basate su analisi di connettività ecologica. Le stepping zones sono elementi del paesaggio che fungono da 'pietre di guado' per la fauna selvatica, facilitando il movimento tra habitat frammentati anche quando non esiste un corridoio continuo. Tipicamente includono: piccole aree naturali isolate, fasce alberate lungo strade e canali, zone umide temporanee, giardini e parchi urbani. L'estrazione avviene tramite query spaziale per identificare le zone che intersecano l'area di interesse. Per ogni zona vengono calcolate: la distanza minima dal campo alla stepping zone più vicina, e la percentuale del campo all'interno di stepping zones. La visualizzazione utilizza una colormap Greens graduata. I dati vettoriali vengono rasterizzati con un bordo di 100m.