Higher levels of no-till agriculture associated with lower PM2.5 in the Corn Belt

Abstract

No-till approaches to agricultural soil management have been encouraged as a means of reducing soil erosion, reducing water pollution, and increasing carbon sequestration. An understudied additional benefit of no-till approaches may be improvements in local air quality. No-till approaches involve reductions in both machinery use and soil erosion, both of which could lead to improvements in air quality. We leverage recent advances in remote sensing and air pollution modelling to examine this question at a landscape scale. Combining data on daily PM2.5 levels with satellite measures of no-till uptake since 2005, we show a strong association between increasing adoption of no-till and reductions in county average PM2.5 pollution over more than 28 million hectares of cropland in the American Corn Belt. The reduction in local pollution implies substantial monetary benefits from reductions in mortality that are roughly one-fourth as large as the estimated carbon benefits. The benefits of mortality reductions are also, by themselves, nearly equal to the current monetary costs of subsidizing no-till practices.