Data: Countries and the Relationship of Crop Yields and Nitrogen Pollution: Wuepper, Le Clech, Zilberman, Mueller, Finger 2020 (Nature Food)

However, causal evidence of countries’ influence is scarce. Using global geospatial datasets and a regression discontinuity design, we provide causal quantifications how much crop yield gaps, nitrogen pollution, and nitrogen pollution per crop yield, are influenced by country-level factors, such as institutions and policies.

We find that there is on average a trade-off between crop yields and nitrogen pollution and countries influence nitrogen pollution much more than crop yields. On average, the countries that reduce their yield gaps (the difference between attainable and attained yield) compared to their neighbors by ~1 percent, produce ~35% more nitrogen pollution than their neighbors. Country characteristics that explain which countries cause the most pollution relative to crop yields include economic development, population size, institutional quality, foreign financial flows to land resources, as well as countries’ overall agricultural intensity and its share in a country’s economy.