Spatio-Temporal Differentiation and Impediments to Agricultural and Rural Modernization Under Regional Coordination: Based on Three Major Economic Circles in Shandong Province

Coordinated regional development of agricultural and rural modernization is essential to remedy sectoral shortcomings and to advance comprehensive rural revitalization. Panel data from 16 cities in Shandong Province (2014–2023) were analyzed using GMI and LMI models to study spatio-temporal evolution and spatial correlation in three economic circles. The Dagum coefficient decomposed regional disparities, while an obstacle degree model identified key hindering factors. The findings were as follows. Agricultural and rural modernization in Shandong has followed a fluctuating but rapid growth trajectory, with a clear spatial hierarchy: Jiaodong > Lunan > Provincial Capital. Spatial agglomeration types HH and LL occurred mainly in Jiaodong and Lunan, respectively. By contrast, spatial outliers of type HL included Dezhou, Jinan and Jining, while LH characterized Rizhao and Dongying. Overall discrepancies in agricultural and rural modernization within the province arose mainly from differences between these economic circles and, on the whole, were converging. Although Provincial Capital has experienced episodic widening of intra-circle disparities, differences within Jiaodong and Lunan have tended to narrow. Persistent constraints on agricultural and rural modernization in Shandong Province included comprehensive control level of soil and water loss, governance expenditure on rural communities, industrialization level of agricultural products, and Agro-product Geographical Indications, while the comprehensive control level of soil and water loss was also the common obstacle factors across three major economic circles, and industrialization level of agricultural products became common to all three from 2020 onward. Each circle should exploit its particular resource endowment and development base. To narrow development gaps among prefecture-level cities, it is essential to clarify functional roles, strengthen inter-city division of labor and cooperation, and promote coordinated regional development of agricultural and rural modernization across the economic circles.