Climate change affects all ecosystems, but its effects may not be immediately apparent. For example, changes in forest biodiversity tend to occur slowly, lagging behind changes in temperature and precipitation within their habitats. Species dominance in California's grasslands changes significantly with changes in temperature and precipitation, research finds, highlighting rapid ecological change and its potential negative impacts on biodiversity.
New research from the University of Michigan shows that grasslands can respond to climate change in real time. The study's lead authors, Kai Zhu and Yiluan Song, liken the phenomenon to financial terms: Forests accumulate "climate debt," while grasslands effectively "pay as you go," adapting to changes as they occur.
"Climate change is definitely going to have an impact on our ecosystem. It's going to come sooner or later," said Song, a postdoc at Michigan's Institute for Social Data and Artificial Intelligence. "The grassland is the faster end."
Zhu, an associate professor at the University of Massachusetts School of Environment and Sustainability, said the work will help the scientific community better understand and predict the effects of climate change. This work will also provide important implications for restoring grassland vegetation.
"If you want to restore grasslands, you have to determine what types of species are going to be planted," Zhu said. "To answer that question, you need to at least take climate change into account."
The research team reported their results today (October 16) in the journal Nature Ecology & Evolution.
The research team, composed of researchers from more than a dozen institutions, has amassed a wealth of data through years of observations of grassland communities in the California Flower Province.
In this biodiversity hotspot that stretches along the U.S. West Coast, the team documented observed trends at 12 sites over several decades. The researchers found that as the region's climate became hotter and drier, species that preferred these conditions became more dominant in plant communities.
The team also included results from long-term global change experiments in the region, showing that climate change can drive changes in communities.
"We know that correlation does not imply causation," Zhu said. "But experimental data allow us to determine cause and effect."
The research team characterized the climate preferences, or ecological niches, of various species in the region. Researchers can then quantify changes in plant communities that are directly related to changes in temperature and precipitation.
Zhu and Song said this approach led to clear and consistent conclusions across the observational and experimental sites studied, which is rare in ecological research.
Even more striking is the rate of ecological change. The rate of change is rapid, comparable to the rate of observed climate change. The researchers stress that such rapid changes in plant communities should not be viewed as adaptations -- at least without further study.
"In my opinion, adaptation gives a positive impression that the system is changing to withstand some of the negative impacts of climate change," Song said. "Rapid changes in grassland communities involve not only the gain of some hotter, drier species, but also the loss of some cooler, wetter species. These changes may have negative impacts, such as the dominance of non-native species and the loss of biodiversity."
Although their study focused on one region, it is believed that the results are applicable to other grasslands, provided they are interpreted in the light of climate dynamics in a specific region. For example, if the climate becomes warmer and wetter, species better suited to survive in these conditions will likely begin to colonize grasslands at a rate that matches climate change.
Compiled from/SciTechDaily