The Impact of Uncertainty Shocks on Agricultural Price Spillover Effects

This study aims to assess the ability of agricultural markets to operate stably in the face of uncertain shocks. This study conducts an empirical analysis using the spillover effect index, based on daily price data of 9 agricultural products from 259 wholesale markets across 12 provinces in China, covering the period from January 1, 2018, to August 31, 2022. The results reveal: First, the agricultural product market system demonstrates remarkable resilience. Although the overall price spillover effects surged sharply during the peak of the shock, they quickly declined as the pandemic normalized, indicating that the shock did not cause permanent structural damage. This finding provides empirical support for the “agricultural market resilience” theory from the perspective of a major public health crisis. Second, the impact of the shock exhibits significant heterogeneity across categories. Perishable agricultural products (e.g., cucumbers, cabbage) and basic staple foods (e.g., wheat, eggs) became key hubs for risk transmission. In contrast, the spillover effects of livestock and poultry products showed high instability. The government should establish a risk-based categorized reserve system, with policy resources tilted towards perishable agricultural products and staple foods. Third, risk transmission follows spatiotemporal evolution patterns. The spillover effects adhere to a dynamic path of “stable-rising-normal,” and interregional linkages are highly pronounced, with over half of the price fluctuations originating from cross-provincial spillovers. Given the high degree of regional interconnectedness, it is essential to break down the “market fragmentation” caused by administrative divisions, and strengthen cross-regional information sharing and logistics coordination.