Land use suitability analysis for town development planning in Nanjing hilly areas: A case study of Tangshan new town, China

Land use suitability analysis plays an important role in sustainable land use and solving environmental problems caused by rapid urban development. A land use suitability mapping approach for town development planning in hilly areas was constructed based on two multi-criteria evaluation methods: Weighted Linear Combination (WLC) and Ordered Weighted Averaging (OWA), to comparatively evaluate and map land use suitability of Tangshan new town in Nanjing, China. Fourteen evaluation factors related to topographic, environmental, socio-economics and historical sites data were used as suitability criteria. The analytic hierarchy process (AHP) method and GIS techniques were integrated into the evaluation models to create the land use suitability map for town development planning. The results of WLC approach showed that 11.4% of the total area is highly suitable while the 48.6% is unsuitable. The results of WLC and OWA approach showed the distribution of degree of land use suitability is almost the same. The areas located at the southern and eastern flat regions are highly suitable for land use, whereas the areas close to the mountain forests, steep slopes, waters, and hot springs, have lower suitability for land use. Sensitivity analysis indicated that the suitability results of the two proposed methods are robust. Indirect validation was achieved by mutual comparison of suitability maps derived from the WLC and OWA methods. It demonstrated that the overall agreement is 90.81% and kappa coefficient is 0.81, indicating that both methods provide very similar spatial suitability distributions. By overlaying the resultant map with the previous master plan map of Tangshan new town, the overlay map once again indicated a satisfactory ecological fit between the two maps. At last, several recommendations are proposed aiming at improving the long-term town development plan for Tangshan new town.