OECD regions have lost 10% of their forests in the last 2 decades and many OECD FUAs – and especially small ones – have seen built-up area growth outpace population growth
Between 2010 and 2020, the new built-up areas across the globe consumed an area as big as Austria. This expansion addresses the growing need for housing and infrastructure, especially in developing and urbanising economies, but it can also harm the environment, biodiversity and many dimensions of well‑being. A growing number of countries have set targets to achieve net zero land take by 2050: for instance, the European Union set a non-binding goal for 2050 and France has legally committed to this objective.
Built-up growth has been widespread in OECD regions and even those experiencing population decline increased built-up areas in the last decade, although at a slower pace than regions that are growing in population. In remote regions, where built-up area growth is largest, built-up surface growth in 2010-20 in regions experiencing population decline was around 11%, faster than the growth seen by metropolitan regions with population growth (Figure 3.29).
Although cities record lower built-up area per capita than others, there are also clear signs of increased unsustainable land use in cities, especially in smaller ones. In nearly 70% of FUAs that saw population growth population in 2010-20, the expansion of built-up areas outpaced the population growth. On average, the increase in built-up areas was 6.6 p.p. higher than population growth in OECD FUAs. Smaller FUAs with fewer than 100 000 inhabitants experienced an average population decrease of 2.1%, but their built‑up areas expanded by 11.6%. Strikingly, smaller FUAs that saw population decline (by -7.4%) expanded their built-up areas by 11% in built-up, while those that gained population (by 6.3%), saw an increase of 12.2%. In contrast, in large FUAs where the population grew by 10%, the increase in built-up areas matched the population growth rate (Figure 3.31 and Figure 3.32). Large FUAs also tend to use space more efficiently, with 92 m2 of built-up area per inhabitant, almost 30 m2 lower than in FUAs with less than 500 000 inhabitants.
Urbanisation is not the only cause of biodiversity loss and the destruction of natural habitats; deforestation and climate change also play significant roles. On average, OECD regions have lost 10% of their forests between 2000 and 2022 (Figure 3.27). Portugal is the most impacted OECD country, with more than half of its forest cover lost. In some regions, forest loss aligns with large forest fires. For example, Centro in Portugal and the Canberra region in Australia lost nearly 60% of their forests from 2000 to 2022. Fires have also severely hit these regions, burning 46% and 82% of their forests from 2000 to 2022.
Natural protected areas are crucial for preserving biodiversity and maintaining natural habitats. Despite this, construction continues to expand in these areas, particularly in remote regions. The Kunming-Montreal Global Biodiversity Framework aims to protect at least 30% of land by 2030 (Convention on Biological Diversity, 2023). Currently, nine OECD countries and about a quarter of OECD large regions have met this goal, with Costa Rica and Luxembourg leading in this effort by protecting more than half of their land. OECD regions protect 21% of their terrestrial areas and the average gap between the most and the least protected region is 31 p.p. (Figure 3.28). Worryingly, from 2010 to 2020, built-up growth consumed an area equal to the Brussels region in Belgium in protected areas that, in principle, have stricter management. In fact, in remote regions, built-up growth was faster in protected areas (18%) than in other (non-protected) remote areas (14%), considering all designated protected areas as recorded in January 2024 (Figure 3.30).
