From decades-long studies of humble grasses, new clues to climate resistance
Nearly 40 years of data on Midwestern prairies reveal that coping with weather extremes isn’t just a numbers game
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Kellogg Biological Station Long Term Ecological Research Site, Michigan State University
view moreCredit: Kellogg Biological Station Long Term Ecological Research Site, Michigan State University
In parts of the Midwest and Great Plains, feathery yellow goldenrod and stands of big bluestem sway alongside Indiangrass and other prairie plants, stretching up to eight feet tall.
Now, in the search for ways to help ecosystems withstand the weather extremes made worse by climate change, it seems that humble grassland plants like these may have some of the answers.
A new analysis of nearly 40 years of data from three tracts of North American grassland confirms what researchers have long said: that biodiversity can be a natural defense against climate threats.
But the study also reveals that coping with climate extremes isn’t just a numbers game where the more species an ecosystem has, the better. Multiple dimensions of biodiversity can help nature survive — and thrive — in harsh conditions, the researchers report.
The findings were published April 7 in the journal Ecology Letters.
When it comes to coping with climate threats and other disturbances, the general rule of thumb has been that having more species helps. But most past studies have been limited to a single location or isolated weather events, said Ashley Darst, a doctoral candidate at Michigan State University who co-led the work.
To address this gap, the 15-person research team analyzed nearly four decades of data collected between 1980 and 2022 at three natural grasslands in Minnesota, Michigan and Kansas, including one of the largest remaining tracts of unplowed tallgrass prairie in North America.
The sites were part of the U.S. Long-Term Ecological Research Network, established in the 1980s by the National Science Foundation to better understand long-term changes to ecosystems.
For years, a generation of researchers have taken careful stock of the plants that grow here, tracking changes in what species are present, their relative abundance, how much plant material they produce. They have also recorded changes in temperature and rainfall over time.
Across the three sites, the researchers identified a total of 28 dry or rainy spells that met the criteria for once-a-decade weather events — conditions so extreme that you might expect to happen only once every 10 years.
In 1988, for example, nearly half of the country was gripped by the worst drought since the Dust Bowl. Rainfall that spring and summer in the central U.S. was the lowest it had been in nearly a century. River levels were at record lows. Yields of corn, soybeans, wheat and other grain crops dropped by 25% to 50% or more. 2012 was another year of deadly heat and scorching drought for the Corn Belt. Crops withered and dried up. Cattle went hungry or were sold off.
At the other extreme, 2019 was marked by drenching rains and record-breaking snowfall that made it the wettest year ever recorded for the Midwest. Farms were inundated, delaying planting season and making it difficult to harvest crops.
Sifting through the data, the researchers found that overall, plots with greater biodiversity were indeed more resistant to extreme climatic events. But the key dimensions of biodiversity that helped them cope in wet years weren’t the same as those for dry years.
“It’s context-dependent,” said study co-lead Joshua Ajowele, a doctoral candidate in biology at the University of North Carolina Greensboro.
In extreme dry years, species-rich plots tended to fare better — as measured by how much plant material they produced — than those with fewer species.
The results also showed that plots whose species abundances were more evenly distributed were more likely to bounce back afterwards.
But in wet years it wasn’t the number of species that mattered, or their relative abundance. Rather, certain species were more important to the health of the ecosystem than others. Plots with high relative abundance of the dominant species were more stable in the face of record rain and flooding.
The link between climate threats and biodiversity goes both ways, the researchers said. Ecosystems weakened by a loss of biodiversity are less resistant to extreme weather. In turn, extreme weather can make it harder for species to hold on, further reducing biodiversity and resistance to future events.
“So you kind of get this weird feedback effect,” said Darst, who is a member of MSU’s Department of Integrative Biology and the Ecology, Evolution, and Behavior Program. “As we get more and more extreme events, we might be eroding the protection against them.”
Extreme weather isn’t the only threat in the era of global change, Ajowele said. Other factors like nutrient pollution from agricultural runoff and nitrogen-laden smog can reduce biodiversity too.
“These factors in combination would have a more detrimental effect,” Ajowele said.
As major droughts and floods occur more often, then, the researchers hope that by understanding how prairie plants cope, they can uncover important lessons for the extremes that lie ahead for other ecosystems too.
“You have to look at more than just species richness,” Darst said.
“Other components of these communities could be important in shaping how they respond to extreme weather,” Ajowele added.
Other study co-authors include researchers from Arizona State University, Colorado State University, Dartmouth College, Denison University, Kansas State University, the University of Massachusetts, and the University of Minnesota.
This research was made possible by funding from the U.S. National Science Foundation (DEB-1234162, DEB-1831944, DEB-1440484, DEB-2025849, DEB-1832042, DEB-2224712, DEB-0823341, DEB-0218210, IOS-9632851, and DEB-9011662).
CITATION: "Multiple community properties drive ecosystem resistance and resilience to extreme climate events across mesic grasslands," Joshua A. Ajowele, Ashley L. Darst, Nameer R. Baker, Rachael R. Brenneman, Caitlin Broderick, Seraina L. Cappelli, Maowei Liang, Mary Linabury, Matthew A. Nieland, Maya Parker-Smith, Smriti Pehim Limbu, Rosalie S. Terry, Moriah L. Young, Max Zaret, Marissa Zaricor. Ecology Letters, April 7, 2026. DOI: 10.1111/ele.70380
Journal
Ecology Letters
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Multiple community properties drive ecosystem resistance and resilience to extreme climate events across mesic grasslands
Article Publication Date
7-Apr-2026
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