Abstract: Compared with cross-provincial integration, provincial integration is more likely to be promoted through enforceable consistent claims, which is the basis for the further advancement of cross-regional integration. Based on this assumption, using the urban panel data of the Yangtze River Delta from 2003 to 2017, this paper constructs the urban function borrowing index and analysis framework, and investigates it from the perspective of urban productivity. The study found that the small and medium-sized cities in the periphery of the Yangtze River Delta have a strong ability to borrow the functions of their respective provincial capitals, while the effect of borrowing the urban functions of Shanghai is poor, which shows the importance of provincial integration. The closer a city is to Shanghai and the larger its scale, the more effectively it can borrow Shanghai's urban functions. The small and medium-sized cities on the periphery of the Yangtze River Delta should use provincial integration to realize the indirect and effective borrowing of Shanghai’s urban functions. The above experience provides a new perspective for the in-depth implementation of the inter provincial integration strategy. Based on the heterogeneity of urban scale and location characteristics, exploring and constructing the practical way and operation mode of integration can accumulate experience for the integration construction of various regions.
