Today's online early edition of the journal Proceedings of the National Academy of Sciences featured the findings of a six-year study conducted by ASU researchers. The study, which measured the effects of climatic variability like droughts and floods on desert grassland, revealed that  overall ecosystem productivity declines. This is because grasses - an important component of the human food system - tend to diminish while shrubs flourish.

“We found that not all species could respond effectively to extreme weather events including both dry and wet conditions,” said Osvaldo Sala, a distinguished sustainability scientist and professor in ASU's School of Life Sciences. “Grasses don’t fare as well as shrubs, which is really important to know because cattle ranchers depend on grasslands to graze their herds. Humans could see a reduction in the production of food — mostly cattle for meat — as the provision of ecosystem services like this one change.”