The world’s open grasslands and the beneficial fires that sustain them have shrunk rapidly over the past two decades, thanks to a massive increase in agriculture, according to a new study led by University of California, Irvine and NASA researchers published today in Science.
Analyzing 1998 to 2015 data from NASA’s Terra and Aqua satellites, the international team found that the total area of Earth’s surface torched by flames had fallen by nearly 25 percent, or 452,000 square miles (1.2 million square kilometers). Decreases were greatest in Central America and South America, across the Eurasian steppe and in northern Africa, home to fast-disappearing lions, rhinoceroses and other iconic species that live on these fire-forged savannas.
The world’s open grasslands and the beneficial fires that sustain them have shrunk rapidly over the past two decades, thanks to a massive increase in agriculture, according to a new study led by University of California, Irvine and NASA researchers published today in Science.
Analyzing 1998 to 2015 data from NASA’s Terra and Aqua satellites, the international team found that the total area of Earth’s surface torched by flames had fallen by nearly 25 percent, or 452,000 square miles (1.2 million square kilometers). Decreases were greatest in Central America and South America, across the Eurasian steppe and in northern Africa, home to fast-disappearing lions, rhinoceroses and other iconic species that live on these fire-forged savannas.
“A billion and a half more people have been added to the planet over the past 20 years, livestock has doubled in many places, and wide-open areas once kept open by fire are now being farmed,” said James Randerson, Chancellor’s Professor of Earth system science at UCI. “Our fire data are a sensitive indicator of the intense pressure humans are placing on these important ecosystems.”
Modelers had forecast that as global temperatures rose, fire risk would soar. But the researchers learned that widely used prediction tools didn’t account for surging population growth or the conversion of grasslands and subsistence farming to industrial agriculture in some of the world’s poorest regions.
Read more at: University of California – Irvine
Photo: Regular fires have long helped maintain healthy grasslands worldwide. But rapid expansion of industrial farming in Africa, Asia, Central America and South America has resulted in a nearly 25 percent decrease in fires and the loss of habitat for endangered lions and other large mammals. (Credits: Center of Environmental Monitoring & Fire Management, Federal University of Tocantins, Brazil)
