As the climate changes, mixed-grass prairie becomes vulnerable to dust-bowl formation.
PHOTO: JOHN SIRLIN/ALAMY STOCK PHOTO
In the 1930s, the central United States turned into a dust bowl, which disrupted agriculture, economies, social structures, and ecosystems and may hold lessons for a future of increasing climate instability. Knapp et al. replicated some of the Dust Bowl conditions in Kansas and Wyoming to determine why a grass characterized by the C3 photosynthetic pathway replaced seemingly better-adapted C4 grasses during the drought despite its preference for cooler temperature and higher soil moisture. The key lies in the timing of precipitation. Drier summer months and wetter cool months during this 4-year period favored the growth of the C3 grasses, which outcompeted the C4 grasses.
Proc. Natl. Acad. Sci. U.S.A. 117, 22249 (2020).
