The effects of climate change could lead to more stable grasslands in Wyoming, according to a recent study conducted northwest of Cheyenne.
Jane Zelikova, a University of Wyoming research scientist, led a team of U.S. Department of Agriculture and UW researchers in conducting the eight-year experiment.
Researchers simulated future predictions for temperature, drought and carbon dioxide conditions in grassland ecosystems.
The study could help state wildlife management officials and ranchers prepare for the effects of climate change.
“Understanding that across dry years that the production is going to remain fairly stable and that other species are going to produce most of the biomass is going to be helpful when thinking about the digestibility and productivity of different grasses,” Zelikova said.
Under exposure to high temperatures and high levels of CO2, dominant grass species gave way to less dominant species, creating a uniform ecosystem, according to the study.
Researchers found that the most resistant grasslands were those subjected to elevated CO2 conditions.
Dana Blumenthal, a USDA ecologist, said elevated CO2 levels boost plants' water-use efficiency. He said that finding could be the most important of the group’s work.
“It does quite a bit to improve water-use efficiency of the species here and counteract the drying effects of warming,” he said.
The eight-year experiment also found a heightened prevalence of invasive plant species under elevated CO2 conditions. Blumenthal said not all changes in grassland composition would be positive for wildlife managers and ranchers.
The group did not directly test the effects of grazing on grasslands competing with climate change.
Introducing livestock would have a significant impact on the dynamic of grasslands, Zelikova said.
UW researchers focused on mixed-grass prairies, with 20 plots subjected to varying degrees of exposure to predicted climatic conditions.
The group is working to develop data about the effects of climate change on the quality of forage species in the experiments.
“We know those species provide valuable forage,” Blumenthal said. “The rest of the picture is the species that are increasing relatively speaking. It’s not clear if the transition from the current dominant species will make it difficult for cattle to effectively utilize that system.”