Fig. 7: Distribution of API regression coefficient of agricultural product production price index.

Panels a–d respectively present the spatial distribution of API regression coefficients in 2016, 2018, and 2022. The legend in each panel denotes the ranges of API regression coefficients, with colors corresponding to specific value intervals. Solid lines represent national boundaries, dash-dot lines indicate the nine-dash line, and small green regions denote south China sea islands. North arrows and scale bars are included to illustrate spatial orientation and distance, respectively.