Expanding agricultural lands is not the sole solution to sustain a burgeoning population. A recent study reveals that curbing air pollution could significantly boost crop yields, thereby preserving valuable land and resources.
Reducing emissions of a single air pollutant by half could lead to a remarkable increase of over 10% in winter crop yields.
The specific pollutant under consideration is nitrogen oxides, which are invisible toxic gases emanating from vehicle exhaust and industrial emissions, including nitrogen dioxide.
Nitrogen oxide emissions rank among the most prevalent air pollutants globally. There is suspicion that exposure to higher levels of these gases may damage plant leaves and impede their growth, although experts are still unraveling the exact mechanisms at play.
Simultaneously, nitrogen oxides serve as precursors to ozone and tiny aerosols in the atmosphere. These can dim sunlight and diminish crop yields.
Researchers discovered that reductions in ozone, particulate matter, nitrogen dioxide, and sulfur dioxide resulted in a 20% increase in U.S. corn and soybean production between 1999 and 2019.
By reducing just four air pollutants, it is estimated that an additional $5 billion worth of crops could be produced annually.
Nitrogen dioxide, being one of the more easily measurable pollutants in a region, can be directly correlated with crop growth. When emitted into the atmosphere, nitrogen dioxide interacts with ultraviolet light in a way that satellites can easily detect.
David Lobell, a professor at Stanford University, explains that nitrogen oxides are invisible to humans, yet new satellites have achieved remarkable precision in mapping them.
This capability, coupled with the ability to measure crop yields from space, presents an opportunity to swiftly enhance our comprehension of how these gases impact agriculture across diverse regions.
The research team compared nitrogen dioxide emissions in various parts of the world with farmland greenness and consistently found a negative impact. The loss of greenery is particularly noticeable.
Utilizing this correlation, the researchers estimated that a 50% reduction in nitrogen dioxide emissions could lead to an approximate 28% increase in winter crop yields. In summer, yields could rise by 16%.
In a scenario where yields typically fluctuate around 1% per year, the potential impact of reducing air pollution in certain regions could be substantial.
Experts emphasize that the primary lesson from this research is that the agricultural benefits of such measures could significantly contribute to addressing the challenge of feeding a growing population.
While the direct effects of nitrogen oxides on plant growth are not yet fully understood, the robust relationship uncovered in this study strongly suggests that air pollution is causing crop losses on a global scale.
