Jiabo Xu

Despite the growing attention on uncontrolled and unprofitable urban sprawling in many African countries, few pragmatic solutions have been raised or effectively implemented. While uncontrolled and unprofitable urban expansions happened primarily due to poor land use management and dysfunctional land market, the cost of land management enforcement and reform is high. This paper suggests that the recently re-emerging special economic zones (SEZs) in Africa could be a practical way of using government intervention to reduce uncontrolled urban expansion and optimize urban land use. By evaluating the spatial impacts of two SEZs on their host cities in Ethiopia and Zambia, this paper demonstrates that SEZs could notably change urban expansion in terms of its speed, direction, and spatial structure. By using SEZs as an experimental area for land policy reform, the government can also effectively unlock a profitable urban development model with the functional primary and secondary land market. However, the diverging results in Ethiopia and Zambia also show that the optimizing effect can be significant only when the government is participatory and can fulfil its public function, including delivering proper planning in advance, lunching land policy reform, and even executing compulsory land acquisition for public interests.

Innovative actors have been studied in both triple helix and quintuple helix framework. Their functions and interactions between each other have been demonstrated, but spatial agglomeration involving all kinds of innovative actors has rarely been deeply analyzed especially in a metropolitan area. Existing innovation theories and relevant research explain why innovative actors agglomerate and cooperate but provide few spatial evidence to support the importance of geographical proximity. Taking the Yangtze River Delta metropolitan area as an example, this study focuses on confirming the importance of geographical proximity between not only technology firms but also other different types of innovative actors on both data and spatial level. Following the triple helix model, namely, technology-, knowledge-, and service-based actors, this study traces the spatial agglomeration and growth of innovative actors since 2008. Primacy index, concentration, and spatial Gini index were used to examine the extent to which three kinds of innovative actors were concentrated in the metropolitan area and a highly centralized hierarchy system with a trend to become multicenter system was thus shown as the spatial distribution structure of innovative actors in the study area. The study also evaluates the innovative performance measured by patents before comparing the innovative capacity of different kinds of innovative actors. By assessing the innovative output structure and leading type of innovative actors, common features of innovatively well-performed cities were concluded as the simultaneous existence of high-output knowledge-based leading actors and a large number of technology-based actors.