The Greening of Drylands Due to Rising CO2 Concentration, but with Potential Downsides

TapTechNews August 1st news, according to YaleEnvironment360, due to the increase of carbon dioxide concentration in the Earth's atmosphere, most drylands have shown a greening phenomenon.

Dryland

Dryland accounts for about 40% of the Earth's land area. Centered around deserts, there are vast savannas, dry woodlands, and sometimes irrigated fields around.

TapTechNews cites data from the International Union for Conservation of Nature (an organization of international conservation scientists) that more than one-third of the world's population lives in drylands, and drylands are also one of the most biodiverse ecosystems in the world.

Climate scientists and ecologists had previously reached a consensus that increasingly arid meteorology and the pressure of human activities would lead to a reduction in vegetation. They often issue warnings about large-scale desertification, which UN officials call the greatest environmental challenge of our time.

However, in most drylands, this expected desertification has not occurred. Instead of shrinking and dying, the vegetation often grows faster and the terrain is expanding, while the deserts are retreating.

Researchers studying the world's carbon and water cycles say this is mainly due to the additional carbon dioxide in the atmosphere.

The Reason for the Greening of Dryland

This is not an isolated case, and the situation is the same from the Sahara Desert in Africa to the arid western India, from the deserts in northern China to southern Africa.

Jason Evans, a water cycle researcher at the Climate Change Research Center of the University of New South Wales in Sydney, Australia, said, Despite the increasing aridity, most drylands globally have shown a greening phenomenon.

The reason, scientists believe, is mainly that the carbon dioxide concentration in the atmosphere has increased by 50% since the pre-industrial era.

The increase of carbon dioxide not only drives climate change but also accelerates the photosynthesis of plants. Even in some of the driest places, carbon dioxide-rich air can allow plants to make more efficient use of scarce water, thereby promoting the growth of vegetation.

According to two recent modeling studies, as we emit more carbon dioxide into the air, the greening of dry areas seems to continue.

But ecologists warn that the additional vegetation may take up scarce water resources, and the greening may have adverse impacts on dryland ecosystems and the people who depend on these ecosystems.