The food supply chain operates in a complex and dynamic external environment, and the external uncertainties from natural and socio-economic environment pose great challenges to the development of the food industry. In particular, the COVID-19 pandemic and Russia–Ukraine conflict have further exacerbated the vulnerability of the global food supply chain. Analyzing the dynamic impacts of external uncertainties on the stability of food supply chain is central to guaranteeing the sustainable security of food supply. Based on the division of food supply chain and the classification of external uncertainties, the TVP-FAVAR-SV model was constructed to explore the dynamic impacts of external uncertainties on food supply chain. It was found that the impacts of external uncertainty elements were significantly different, the combination of different external uncertainty elements aggravated or reduced the risks of food supply chain. And some uncertainty elements had both positive and negative impacts in the whole sample period, as the magnitude and direction of the impacts of various uncertainties in different periods had time-varying characteristics.

Many studies shed light on online shopping adoption and its determinants, most of which were conducted in developed countries and focused on sociodemographic factors. However, the influence of spatial attributes remains unclear or underestimated, especially in emerging economies. China is the largest e-commerce market in terms of the number of e-shoppers and the volume of online retail sales, with a distinctive geographical pattern of e-shopping usage. This study developed a conceptual model of China’s e-shopping adoption, examined the spatial characteristics of the e-shopping usage across 1918 counties, and explored its key drivers. The findings indicate a digital divide of e-shopping in China, with counties in metropolitan areas having a relatively high online shopping index (SI) value. The counties’ online shopping levels in China decrease from the eastern coastal regions to the rural-mountainous regions in west China. This study also found that the key drivers of e-shopping adoption are the rate of urbanization, local delivery systems, and the internet connection, which indicates that geographical attributes, rather than socioeconomic problems, have to be solved for improving online shopping adoption.

The digital divide has loomed as a sustainable development issue for over two decades and there has been much research in terms of efforts to measure the digital divide from different dimensions and scales. Drawing on spatial agglomeration analysis and multiple linear regression, this paper aims to reveal the spatiotemporal pattern of the prefectural digital divide in China and its determinants. The results show that there is a significant prefectural digital divide in China that is characterized by a decline of ICT development index (IDI) values from the east to the west as well as from core cities to more peripheral ones. Cities with high IDI values are mainly concentrated in large metropolitan areas in eastern China, whereas cities with low values tend to concentrate in poverty stricken regions in central and western China. However, the digital divide has been characterized by a reduction from 2001 to 2015. The results also show that both economic and educational factors have significant influences on the prefectural digital divide in China. During the early stages, the percentage of university students, urban residential income, and the urbanization rate were key factors. However, after 2010, the adult literacy rate and rural residential income determined the digital divide.

The minimum purchase price policy for wheat and rice implemented by the Chinese government has achieved the fundamental goals of stabilizing grain prices, promoting production, and ensuring food security. This policy has also had negative impacts such as domestic and foreign price spreads and continuous increases in stocks and imports, which are not conducive to China’s grain security development and thus unsustainable. Therefore, this paper builds a partial equilibrium model of China’s grain market by simulating the effects of canceling or reducing the minimum purchase price on the market price, production, consumption, stock, and net import of wheat and then evaluates the sustainability of various adjustment programs. The research results show that first, lowering the minimum purchase price of wheat can reduce the domestic and foreign price spread, stock, and imports to a certain extent; however, it cannot fundamentally solve the negative impact of this policy. Second, cancellation of the minimum wheat purchase price policy can significantly reduce domestic and foreign price spread, stock, and imports; however, it will also significantly reduce wheat production and threaten China’s grain security. Third, cancellation of the minimum wheat purchase price and the increase in agricultural production subsidies can solve the negative impact of the minimum purchase price policy and reduce the impact of the cancellation of the minimum purchase price policy on grain supply security. This policy adjustment is more sustainable than China’s current policy. Finally, this paper asserts that China’s grain price policy reform will influence and have implications for stakeholders in the global grain industry.