Analysis of the threshold effect of agricultural industrial agglomeration and industrial structure upgrading on sustainable agricultural development in China

Sustainable agricultural development plays a key role in natural resource conservation, environmental protection and the promotion of rural revitalization. Scholars agree on the need to implement agricultural industrial agglomeration and promote industrial structure upgrading to boost agricultural development. However, the contradiction between them is also coming to the fore, and the rapid development of industry has brought huge pressure on agricultural development by influencing resources and the environment. Therefore, the complicated nonlinear relationship between agricultural industrial agglomeration, industrial structure upgrading and sustainable agricultural development requires further clarification. Using panel data from 1997 to 2019, this study measures the agricultural sustainable development index (ASDI) in 31 provinces in China based on potential resources and environmental capacity. The nonlinear relationships between agricultural industrial agglomeration, industrial structure upgrading and sustainable agricultural development are then examined by panel threshold models. The results are as follows. (1) Taking 2002 and 2007 as the demarcation point, the national average ASDI presents a trend of rising first, then falling, and finally rising, and significant spatial differences existed. (2) Constrained arable land space and environmental space are the main drivers of the decline in the ASDI. (3) Agricultural industrial agglomeration and industrial structure upgrading had a nonlinear effect on sustainable agricultural development, and both of them also had threshold effects. (4) China is currently in the promotion stage for agricultural industrial agglomeration, but provinces have entered the restriction stage for industrial structure upgrading. These results may help China design relevant policies for sustainable agricultural development from an industrial development perspective.