A new way to analyze soil organic matter will help predict climate change
WACO, TX- A new way to analyze the chemical makeup of soil organic matter will help scientists predict how soils store carbon — and how soil carbon may affect climate in the future, says a Baylor University researcher .
A study by scientists from Iowa State University and Baylor University, published in the academic journal nature geoscience, used an archive of soil data from a wide range of environments across North America – including tundra, tropical rainforests, deserts and grasslands – to find patterns to better understand the formation of soil organic matter, which is mainly composed of residues left by dead plants and micro-organisms.
The researchers analyzed samples of 42 soils from the archives of the National Ecological Observatory Network and samples taken from other sites, representing all major soil types on the continent.
The soils were analyzed by William C. Hockaday, Ph.D., Associate Professor of Geosciences at Baylor University, and Visiting Scholar Chenglong Ye, Postdoctoral Researcher at Nanjing Agricultural University, Baylor Molecular Biogeochemistry Laboratory. They used a technique called nuclear magnetic resonance spectroscopy, which allowed them to analyze the chemical structure and composition of natural organic molecules in the soil.
“Soils are a foundation of society by providing food, clean water and clean air,” Hockaday said. “Soils also play a major role in climate change as one of the largest carbon reservoirs on the planet. Even so, the chemical composition of this carbon has been debated by scientists for over 100 years. »
“With this study, we wanted to answer the questions of whether organic matter is chemically similar across environments or varies in predictable ways across environments,” said study lead author Steven Hall, Ph.D. and Assistant Professor of Ecology, Evolution, and Organismal Biology at Iowa State.
The study revealed patterns in soil organic matter chemistry that held true across climates. Understanding these patterns, or rules for how and why organic matter forms and persists in soil, will help scientists predict how soils in various ecosystems store carbon. Carbon can contribute to climate change when released from the soil into the atmosphere as a greenhouse gas. A better understanding of the types of soil carbon existing in different environments can paint a clearer picture of how soil carbon can affect climate and how future climate change can affect the soil carbon pool, the researchers said. .
“This study brought together a strong team of scientists, and for me it was the first time looking at chemical patterns on a continental scale,” Hockaday said. “It’s exciting and rewarding when you inform a long-standing debate and offer an explanation of a major pattern that exists in nature.”