Quantifying the temporal stability of international fertilizer trade networks.

This article focuses on analyzing the temporal stability of international fertilizer trade networks for the three main nutrients: nitrogen (N), phosphorus (P), and potash (K). It introduces a novel metric called the structural inheritance index to distinguish the stability of existing trade structures from the effects of network growth, comparing it with mutual information and the Jaccard index. Using trade data from 1990 to 2018, the study finds that all three nutrient trade networks have increased in stability over time, with the P trade initially less stable but catching up, the K trade showing high core stability yet vulnerability to shocks, and the N trade being the most stable overall due to a stable medium-weight sub-network. The research concludes that these fertilizer trade systems have reached a steady state, and the proposed methods offer a multidimensional approach applicable to other complex temporal networks.