Settlement changes after peak population: Land system projections for China until 2050: Fid-Bau Portal

Settlement changes after peak population: Land system projections for China until 2050

Wang, Yuan / van Vliet, Jasper / Debonne, Niels / Pu, Lijie / Verburg, Peter H

Highlights • We simulate settlement system changes in China until 2050. • Our model includes multiple settlement systems, allowing for different urbanization trajectories. • Future changes include both urban development and a development of village landscapes. • Increase in built-up land mostly leads to a decline in natural areas via cropland displacement. • Maintaining current population densities can avoid a loss of 57–73 × 10³ km² of natural land.

Abstract China has experienced unprecedented urbanization in the past few decades, fueled by population growth, economic development, and rural to urban migration. In the future, economic growth as well as rural to urban migration is expected to continue, but demographic scenarios indicate that the population of China will peak and subsequently decline. As a result, it is unsure how urban areas will develop after peak population. In this study we further develop the CLUMondo land system model to simulate land system changes in China until 2050. Our application represents a range of settlement systems, from dense urban areas to village landscapes, differing in their built-up area as well as their population density to enable the simulation of different settlement change trajectories. Our results show that a UN high population scenario in combination with a continued decline in population density leads to an increase of built-up land of about 48%. Conversely, the UN low population scenario in combination with a constant population density could be accommodated within the current amount of built-up land in China. Due to prevailing cropland protection policies, increase in built-up land will mostly lead to a loss of natural areas, hence our scenarios highlight the opportunity space for limiting land take and saving natural areas. This study also demonstrates the need for more nuanced representation of settlement systems for the assessment of land change trajectories.