Are there differences in the forces driving the conversion of different non-urban lands into urban use? A case study of Beijing.

Examining the heterogeneous factors behind the conversion of various types of non-urban land into urban use is of great significance for controlling urban land expansion and formulating reasonable land use policies. Taking Beijing as an example, this study identified the spatial patterns of urban expansion in China's large cities and then explored the different driving factors behind its various sources. The results showed that, from 2001 to 2010, Beijing's urban land presented a compound expansion mode in which multiple spatial modes coexisted. Urban encroachment contributed differently to the loss of different non-urban lands. Cultivated land and ecological land were the main sources of newly developed urban land, of which the conversion was driven jointly by topography, location, transportation, socioeconomic development, and spatial planning. Moreover, the main factors behind the conversion of various land types varied: closing to existing built-up area and infrastructures increases the conversion probability of most land types; socioeconomic development has common but differentiated effects; governments at different levels have their influences on the conversion of different types of non-urban land. Based on the results, this study suggested the importance of considering varied approaches in managing non-urban lands to better controlling their conversion into urban use and the different roles that could be played by governments at various levels.