The increasing global environmental consequences of a weakening US-China crop trade relationship

The consideration of tariffs on China's imports of US agricultural products has focused on economic impacts, while the environmental consequences have received less attention. Here we use a global computable general equilibrium model to evaluate long-term crop portfolio changes induced by China's retaliatory agricultural tariffs and thereby assess the environmental stresses imposed by different crop production portfolios based on region-specific and crop-specific databases. We show that China's tariffs cause unintended increases in nitrogen and phosphorus pollution and blue water extraction in the United States as farmers shift from soybeans to more pollution-causing crops. If diverted to Brazil, China's soybean demands would reduce Brazilian stresses of nitrogen pollution and water use through crop portfolio changes, but may add additional pressures on phosphorus pollution and deforestation. On a global scale, trade policies could help to reduce nutrient pollution and water source depletion by promoting crop production where it is most efficient in terms of nutrient and water use. The potential environmental consequences driven by US-China crop trade tension are considerable and could spill over to other countries, especially Brazil and other South American countries, through international trade. Such consequences are predominantly driven by China's proposed retaliation on US soybeans.

Automated summary

The study found that China's tariffs on US agricultural products cause American farmers to shift to more pollution-causing crops, leading to increases in nitrogen and phosphorus pollution as well as water usage. If redirected to Brazil, while it could reduce nitrogen pollution and water stress, it may worsen phosphorus pollution and deforestation. Trade policies promoting crop production in the most efficient way in terms of nutrient and water use could help reduce pollution and water depletion. The potential environmental consequences of the US-China crop trade tensions are significant and could affect other countries, particularly Brazil and other South American countries, through international trade.