关键词: 城市蔓延, 非正式聚落, 扩展强度指数, 姆万扎, 坦桑尼亚, 一带一路

Abstract: The urban sprawl problem of Mwanza, the second largest city in Tanzania and among the fastest growing cities in Sub-Saharan Africa, has become increasingly prominent in recent years. Based on the land-use classification data(2000, 2010 and 2015), supplemented with field surveys, methods including GIS spatial analysis, elasticity ratio of urban land growth and landscape index were employed to study the pattern and influencing factors of urban sprawl for Mwanza. The findings indicated that: 1）Mwanza experienced rapid spatial growth mainly in the form of informal settlements during 2000 to 2015. Bare lands followed by vegetation were mostly occupied during the urban sprawl, and the encroachment on vegetation was accelerating. 2）The patterns of the sprawl mainly took place along the three major roads, and were dominated by corridor expansion, coupled with filling-up expansion, forming a finger-like urban spatial form. The compactness of the built-up area gradually decreased and its shape became irregular. 3）The urban sprawl showed obviously distance attenuation feature, and the expansion intensity was highest towards the southeast direction. 4）The urban sprawl of Mwanza was mainly influenced by the growth of the population and economy, the improvement of traffic condition, land system and the lack of effective planning. Strengthen the planning and construction of both secondary and local roads, and make timely, effective and context-based urban planning are recommended ways to curb further urban sprawl of Mwanza.

Key words: urban sprawl, informal settlements, expansion intensity index, Mwanza, Tanzania, the Belt and Road