This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: When a 10,000-year-old prairie is plowed up to plant corn or a savanna is consumed by a strip mall, these once-grassy expanses, if left to regrow, can eventually look vaguely like they did before. But a growing body of research suggests that what comes back isn't the same as what was lost, even decades later.
And now scientists are starting to understand why. That's the takeaway of a new study of grasslands worldwide published in the journal Proceedings of the National Academy of Sciences. The results are important because grasslands are more than just treeless expanses.
They can look barren to the untrained eye, but they have extensive underground roots that reduce water runoff, control erosion and store a third of Earth's terrestrial carbon. Grasslands provide fodder for livestock and habitat for unique plants and animals ranging from American bison and African wildebeests to the great bustards of Asia. Covering nearly a quarter of Earth's land, they also help support the livelihoods of more than a billion people worldwide.
Take the vast 5,000-mile belt of grasslands that is the Eurasian steppe, which stretches from Hungary to China. The prairies of North America's Great Plains. Yet over the past couple of centuries, ancient grasslands around the world have largely been converted into cropland, tree plantations or development as cities expand.
In Brazil, for example, a species-rich savanna known as the Cerrado loses an area the size of London every three months. India's savannas shrank from 100 million acres (156,000 square miles) in 1880 to 60 million acres (94,000 square miles) in 2010, according to one study. And in North America's grasslands, less than half of their historical acreage remains.
At the same time, millions of acres of farmland are abandoned worldwide, providing an opportunity for secondary grasslands to spring up in their place. Previous research by the lead author of the new study, Ashish Nerlekar, a postdoctoral researcher at Michigan State University, has shown that these newer grasslands can take decades to recover the biodiversity of ancient grasslands and that, even after centuries of regrowth, certain plant species are still missing. Discover the latest in science, tech, and space with over 100,000 subscribers who rely on Phys.org for daily insights. d research that matter—daily or weekly.
Extract — continue reading at the source.
