E-commerce development and its contribution to agricultural non-point source pollution control: Evidence from 283 cities in China.

Agricultural non-point source (ANPS) pollution is a pressing environmental issue in developing countries that poses a substantial threat to sustainable development. With the rapid growth of e-commerce and its great penetration and transformation in many socioeconomic sectors, e-commerce plus agriculture is widely regarded as the solution to sustainable agricultural development. However, the environmental impacts of e-commerce on agriculture, as well as the underlying mechanisms have yet to be fully explored and verified. Based on China's practices of e-commerce development and its integration with agriculture, a panel dataset of 283 prefecture-level cities from 2009 to 2019 was collected, and a spatial difference in difference (SDID) model combined with a Durbin model was constructed to examine the local and spatial spillover effects of e-commerce development on ANPS pollution. It is found out that e-commerce development has significant positive environmental impacts achieved by stimulating industrial structure upgrading and promoting green technology innovation, while the mechanism of cultivation scaling up tends to aggravate the ANPS pollution. Spatial analysis demonstrates that e-commerce development also helps alleviate the ANPS pollution of neighboring regions with a decayed effect over a distance. Meanwhile, the impact of e-commerce on mitigating ANPS pollution shows regional heterogeneity. Those developed regions present significant positive effects, while those regions dominated by agriculture economy and without sufficient supporting facilities for e-commerce development, show significant negative effects. Therefore, we argue that the positive environmental contribution of e-commerce is not bound to happen but instead is contingent, while policies should be adapted to local conditions and enhanced to encourage the integration of e-commerce and other socioeconomic sectors, in order to develop beyond the immature pioneering stage.

Assessing the Nutrient Adequacy in China's Food Supply from 1965 to 2018.

Nutritional intake has important impacts on human health. A sufficient supply of nutrients is required to ensure high-level nutrition in a population. Assessment of nutrient supply adequacy can help to develop evidence-based policies and thereby promote public health. This study estimates the supply adequacy of nutrients in China's food system from 1965 to 2018 at the national level, aiming to reveal whether the supply of nutrients meets the demand. The results show that the nutrient supply in China's food system has experienced a sharp increase in the past five decades, and the deficiency in nutrient supply has been greatly mitigated. Although most nutrients such as potassium are already sufficiently supplied in China's current food system, some nutrients, especially calcium and zinc, still need a further enlarged supply to improve the nutrition condition of the Chinese population. Besides encouraging a healthy diet, supply-side regulation, e.g., fortification and enrichment, is also needed to improve nutrient availability. This study helps people better understand the development and current situation of nutrient adequacy in China's food supply, thereby providing information and implications for policymakers.

Using the Machine Learning Method to Study the Environmental Footprints Embodied in Chinese Diet.

The food system profoundly affects the sustainable development of the environment and resources. Numerous studies have shown that the food consumption patterns of Chinese residents will bring certain pressure to the environment. Food consumption patterns have individual differences. Therefore, reducing the pressure of food consumption patterns on the environment requires the precise positioning of people with high consumption tendencies. Based on the related concepts of the machine learning method, this paper designs an identification method of the population with a high environmental footprint by using a decision tree as the core and realizes the automatic identification of a large number of users. By using the microdata provided by CHNS(the China Health and Nutrition Survey), we study the relationship between residents' dietary intake and environmental resource consumption. First, we find that the impact of residents' food system on the environment shows a certain logistic normal distribution trend. Then, through the decision tree algorithm, we find that four demographic characteristics of gender, income level, education level, and region have the greatest impact on residents' environmental footprint, where the consumption trends of different characteristics are also significantly different. At the same time, we also use the decision tree to identify the population characteristics with high consumption tendency. This method can effectively improve the identification coverage and accuracy rate and promotes the improvement of residents' food consumption patterns.

Demographic Scenarios of Future Environmental Footprints of Healthy Diets in China.

Dietary improvement not only benefits human health conditions, but also offers the potential to reduce the human food system's environmental impact. With the world's largest population and people's bourgeoning lifestyle, China's food system is set to impose increasing pressures on the environment. We evaluated the minimum environmental footprints, including carbon footprint (CF), water footprint (WF) and ecological footprint (EF), of China's food systems into 2100. The minimum footprints of healthy eating are informative to policymakers when setting the environmental constraints for food systems. The results demonstrate that the minimum CF, WF and EF all increase in the near future and peak around 2030 to 2035, under different population scenarios. After the peak, population decline and aging result in decreasing trends of all environmental footprints until 2100. Considering age-gender specific nutritional needs, the food demands of teenagers in the 14-17 year group require the largest environmental footprints across the three indicators. Moreover, men's nutritional needs also lead to larger environmental footprints than women's across all age groups. By 2100, the minimum CF, WF and EF associated with China's food systems range from 616 to 899 million tons, 654 to 953 km3 and 6513 to 9500 billion gm2 respectively under different population scenarios. This study builds a bridge between demography and the environmental footprints of diet and demonstrates that the minimum environmental footprints of diet could vary by up to 46% in 2100 under different demographic scenarios. The results suggest to policymakers that setting the environmental constraints of food systems should be integrated with the planning of a future demographic path.

Are the Chinese Moving toward a Healthy Diet? Evidence from Macro Data from 1961 to 2017.

The change in diet structure is one of the critical features of social transformation, and diet structure is directly related to human health. In China, with rapid economic development, changes in the diet structure of the population have begun and are proceeding at a fairly rapid rate. In order to reveal how the Chinese diet is approaching or deviating from the nutritional goal, a novel index, NDBI (National Dietary Balance Index), is developed in this study to investigate the Chinese diet from 1961 to 2017 at a national level. The results show that the Chinese diet has transitioned from the under-intake stage to the over-intake stage. Before the 1980s, Chinese people ate all foods inadequately except staple foods; after the 1980s, the issue of under-intake began to fade, and the intake of meats even became excessive. The intake of staple foods is always excessive during this period. Currently, the Chinese diet is still unhealthy because of the inadequate intake of dairy products and the excessive intake of staple foods and meats. By evaluating diet structure on a national level, this study can help people to better understand how the Chinese diet deviated from the nutritional goal and provides information for policymakers intervening in China's food consumption.