Soil sealing

Description of the results

Soil is a limited and essential resource that is used not only for agriculture, forestry and construction, but also as a habitat for animals and plants. In urban and transport areas, some of the soil is sealed by the buildings built upon it. Undeveloped areas such as open spaces, operational and recreational areas as well as traffic areas which are also partly covered with concrete, asphalt, paving stones or water-bound surfaces and are therefore partly or completely sealed (1). The conservation of unsealed soil is an important indicator of climate regulation.

Data on soil sealing has only been collected annually since 2012. Prior to that, data were only collected for single years. Figure 1 shows a steady increase in soil consumption in South Tyrol from 2006 (19 043 ha) to 2023 (20 253 ha). The annual increases vary from an increase of just under 50 ha in 2016 to around 200 ha in 2017. Figure 2 shows the percentage of land consumption. In 2006, 2.58 % of the provincial territory was sealed, increasing to 2.74% in 2023 (+0.16%). In comparison, the share of sealed surfaces in South Tyrol is between two and three percent, while the Italian average is at about seven percent (Figure 3). After Valle d'Aosta, South Tyrol has the lowest sealed surface area in Italy in 2020 (2). However, only about 5.5% of South Tyrol's land area is available for permanent settlement, as the rest consists of uninhabitable glacier, mountain, forest, water and protected areas. Due to the limited space available, land is a particularly precious resource in South Tyrol.

By signing the UN Global Agenda for Sustainable Development, which sets out the Sustainable Development Goals (SDGs), Italy agreed to participate in the monitoring of these goals using a system of indicators that includes land consumption. By 2050, EU member states are required to reduce their net land consumption to “net zero” per cent. As such, South Tyrol intends to limit building activity to residential areas.

Method

Data on soil sealing in Italy and South Tyrol are provided by the National Institute for Environmental Protection and Research ISPRA (Istituto Superiore per la Protezione e la Ricerca ambientale) (2). The underlying geodata are generated by classifying satellite images provided by the Copernicus program. The classification system divides land use into two main categories, permanent and reversible, which form a second level of classification. Knowledge of land use is available throughout Italy thanks to the data updated in 2018 by the National System for Environmental Protection (SNPA), both in tabular form and as a geospatial dataset. The map in Figure 3 shows the level of detail provided by satellite imagery for the municipality of Bolzano in 2020. For reasons of readability, only a small section is shown here.

 Sectors affected

• Settlement

• Biodiversity

• Soil

• Natural hazard

• Ecosystem service

• Health

Related indicators

References

(1) Umweltbundesamt: Was ist Bodenversiegelung?

2) Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA) 2021: Consumo di suolo, dinamiche territoriali e servizi ecosistemici. Edizione 2021:  ISPRA - Istituto Superiore per la Protezione e la Ricerca Ambientale; http://www.consumosuolo.isprambiente.it

Contact

Eurac Research: Peter Laner, Institute for Regional Development;

Data: Kathrin Renner, Center for Climate Change and Transformation