4.1.3. Containment

In the last decades, many containment interventions have been implemented in Europe with the objective of reducing land take. As a consequence, a number of sustainable strategies and green belts have been designed (e.g., the Grüner Ring in Leipzig, Corona Verde in Torino) to limit and control urban growth. Numerous interventions of this kind have proven successful in promoting sustainable development. For example, the Corona Verde strategy [40] envisages an ecological 'crown' around the metropolitan area of Torino (Italy), and brings together different intersectoral policies in order to reduce urban land consumption and to increase the quality of the rural–urban environment (e.g., through the mitigation and renaturation of infrastructural barriers, the conservation of the rural heritage).

Certain characteristics, such as the support of a strong political will and the adoption of long-term visions, seem to improve the implementation of these interventions. For example, the German governmen<sup>t</sup> set the 30 hectares' target, with the ambitious goal of reducing annual land consumption to 30 hectares per day nationwide by 2020 (Umweltbundesamt— UBA, German Environment Agency: www.umweltbundesamt.de/en/ (accessed on 15 March 2021)). Cooperation that goes beyond municipal boundaries is another characteristic that often improves the successfulness of containment interventions. This is the case of Vision Rheintal (Austria) [41]. For the expert informant, its success is partly due to intramunicipal cooperation, as well as engagemen<sup>t</sup> with a heterogeneous group of experts (thus, promoting the transfer of expert knowledge) and the adoption of a holistic approach.

The adoption of legal binding instruments also seems to improve these interventions. For example, the 2014 Tuscany Regional Law on soil consumption (Italy) requires municipalities to delimit the borders of their more densely urbanized areas and to promote the urbanization of empty plots through simplified regulations and incentives. Non-residential transformations outside urbanized areas, which involve the consumption of new land, are only allowed if the co-planning conference provides a favorable opinion (Legge Regionale Toscana 65/2014). Similarly, the 2009 Law for the City of Sofia (Bulgaria), which works together with the city's General Urban Development Plan (GUDP), is considered to have produced positive outcomes, in particular by stating that "the designation of existing green plots or parts thereof in the urbanized territories, created according to the development plans cannot be changed" (art. 9). The GUDP, however, seems to have been less successful. In fact, inconsistencies seem to exist between the plan's overall goals and some of its measures and implementation tools [42]. Thus, certain interventions, if not implemented correctly, might lead to a discrepancy between the desired objectives and the actual outcomes. This might also be exacerbated by a lack of political will, technical capability and scarcity of economic resources.

Moreover, certain containment initiatives may turn out to be counterproductive for the promotion of sustainable land use. This seems to be the case of the Cork Area Strategic Plan (Ireland), which provides a long-term vision for the development of the Cork City-Region up to 2020. The expert reporting the intervention noted that, even though it aims to reduce urbanization in the countryside, an overexploitation of natural resources still occurs, and that the strategy is based on a pro-growth approach.
