How Soil Microbes May Control the Future of Our Planet
The soil beneath our feet is a huge carbon bank storing up to approximately three times more carbon than the entire atmosphere. That makes it a significant player in the future of our climate. If even a small fraction of the carbon escapes into the air as carbon dioxide, it could accelerate planetary heating. But what determines whether the carbon stays in the ground or escapes? According to new research published in the journal Nature Climate Change, water is the deciding factor. The wetter the soil, the more carbon stays in the ground.
Simulating future weather
Researchers reached this conclusion following a 12-year experiment on 48 plots of land in Oklahoma, where they monitored the soil’s response to warming and varying rainfall levels. Some plots were kept at normal temperatures while others were warmed by 3°C using an infrared heater to simulate a future, hotter climate.
The team also controlled the amount of water reaching each plot, using rain-out shelters to create drought conditions and adding extra water to simulate wet years.
Each year, the researchers conducted a checkup of each plot to see how wet and dry conditions affected the land. They measured the total carbon in the soils, the weight of the growing plants and the soil’s release of carbon using soil chambers that capture and track gas emissions. They also analyzed the genetic material of soil microbial communities to see how bacterial and fungal populations changed over time.