Year: 2024
Type: report
Abstract: As the climate changes, droughts may become more severe. Scientists are uncertain about how drought will affect the natural world, particularly the bacteria, fungi, and other microbes that live in soils and control the Earth’s flows of carbon and nutrients. Researchers at the University of California, Irvine, and Lawrence Berkeley National Laboratory teamed up to study how microbes at the soil surface change with drought and what that means for the carbon cycle. Since 2007, the researchers have used shelters with retractable roofs to prevent nearly half of normal rainfall from reaching grass and shrub landscapes, and their soil microbiomes, in Southern California. The researchers used field experiments, laboratory assays, and genetic sequencing to test if the microbes in these landscapes are evolving in response to drought. The team sought to understand how evolution happened and what it means for the carbon cycle. Mathematical models were used to learn how evolution might interact with other biological processes and play out in different environments. One of the study team’s key conclusions was that microbial evolution is faster and more important than previously known. In one experiment, the researchers observed bacteria evolving in real time after being transplanted into different climates in Southern California. Although microbe species often rise and fall in numbers when the climate changes, the genes within a species can also shift rapidly. This result means that microbes have more ways to cope with climate change than originally thought. Another key finding was that microbes can evolve in different directions depending on the environment and how it’s changing. Many microbes have evolved to switch genes on and off as needed to grow and survive. That adaptation allows bacteria and fungi to produce metabolites that protect them against heat or drought. The researchers also discovered that microbes from different places vary widely in their genetic toolkits. For example, some microbes have many different genes that allow for a “Jack-of-all-trades” strategy, whereas other microbes are more genetically streamlined. Knowing about these strategies is crucial because they affect microbes’ climate change resilience and impact on the carbon cycle. Importantly, this project generated new mathematical models that predict how microbiomes adapt to environmental change. These models show that changes in climate, especially severe drought, can leave a lasting imprint on the microbiome because some species are lost and never come back. However, in models with migration or evolution, those missing microbes may recover, along with their contributions to the carbon cycle. Overall, this project advanced scientific understanding of how microbes shift, evolve, and adapt to climate changes such as drought. New mathematical models are including this knowledge in their predictions of microbiomes and the beneficial services they provide in landscapes around the world.
DOI: 10.2172/2263525
Institution: University of California, Irvine
Language: English
Subfield: Soil Science
Domain: Life Sciences
SDGs: Climate action, Life on land
Open Access status: gold
OpenAlex ID: W4392860750