Desertification was described as “the greatest environmental challenge of our time” by the UN’s top drylands official in 2010, Luc Gnacadja. Since the early 1980s, a quarter of the planet’s inhabitable land has been despoiled; now, climate change is making things worse.
Earth.Org takes a closer look.
What is Desertification?
Desertification is quite hard to define, but generally speaking, it is the process by which lands become infertile through a variety, and often a combination of mechanisms.
One of these is soil erosion, by which it is stripped of nutrient-rich topsoil by the action of wind, water and waves, all natural processes which are exacerbated by poor agricultural practices that leave the land bare.
Overuse of fertilizers can leave the ground acidified, just as saltwater intrusion can leave it salinated. And finally, climate change can make droughts too intense, and wildfires too frequent for the land to bear.
Where Desertification is Happening
Desertification is assailing the world’s arable lands. Increased drought, poor land-use decisions and bad agricultural practices leaves much of our land open to erosion, nutrient loss and other problems, eventually leaving it infertile.
Most of the world’s soil is currently in degraded condition, and this could rapidly become the biggest environmental problem on earth.
We used the Normalized Differentiated Vegetation Index (NDVI), a remote sensing technique, to look at the loss of greenery in some of the most rapidly-desertifying countries in the world.
Please remember that desertification is a complex process, and loss of greenery is, at best, a proxy of sorts but not an exact indicator of desertified land. Green cover varies year to year, though to a point, so the images below will show more of a general trend than the exact progress of desertification.
China’s share of desert land has rapidly increased since the 1980s and now stands at 30% of its total area. The creeping deserts threaten farmland, forcing people to abandon their homes, and will lead to food insecurity if they aren’t addressed.
Since 2012, a USD 80 million World-Bank financed project has been helping control desertification and rehabilitate natural vegetation in seven counties and cities in Ningxia, an autonomous region surrounded by three major deserts.
Combinations of agricultural techniques and grazing bans have led to the “re-greening” of certain areas, and over 21,000 hectares of desert have been worked on.
People in Yemen lead difficult lives, with 75% of its population under the poverty line (US $3.10 a day). Difficult, arid conditions are compounded by a foreign-backed civil war and climate change, which increases the frequency, length and intensity of droughts.
Farmers have had to abandon their land as it dried up and cattle died of starvation, forced to move into big cities to work menial jobs.
The country also faces heavy sandstorms, which cause rapid soil erosion and damage to existing crops. According to the UN Office for the Coordination of Humanitarian Affairs (OCHA), Yemen loses 20% of its arable land to sandstorms each year.
Population growth and food demand in Kenya have led to overgrazing in increasingly dry lands, partly driven by climate change. On top of this, rampant deforestation is further damaging the land, contributing to a rapid decline of soil quality in Kenya.
Various policies and strategies are being implemented to combat desertification, but Kenya needs to address its growing inequality and mismanaged resource-usage for this to be effective.
Mali is located in West Africa, straddling the Sahara so 65% of its area is desert or semi-desert. The Sahara itself is steadily expanding southwards at a rate of 48km per year, forcing many to evacuate and leave their homes behind.
Three-quarters of the population rely on agriculture for their food and income, and as the population grows and arable land dwindles, the situation becomes more untenable. Moreover, lack of food security feeds conflictual thinking, and civil strife has plagued the country for decades.
Finally, climate change is accelerating all of the above through increased drought: the UN says Mali’s average rainfall has dropped 30% since 1998.
Russian scientists and officials in vulnerable areas have been calling for help to combat desertification since the 1990s. Unregulated, excessive grazing is said to be the main cause, and it is compounded by sandstorms and drought.
Unfortunately, these lands are typically settled by different ethnic and nomadic tribes, who get less attention than others might, yet rely on the land all the more. One such community is that of the Nogai, living on the Nogai steppe in the Russian Republic of Dagestan. They’ve witnessed two landmark lakes disappear over the last 50 years, along with their farmland turning into sandy dunes.
The region of Kamylkia, just north of Dagestan, suffering the same fate, declared a state of emergency, which prompted UN and Russian governmental action. Farmers are now subsidized to encourage planting of trees and other desert-stopping plants, but large-scale grazing still hasn’t been banned.
The Syrian steppes have desertified terribly over the last few decades. Authorities claim it is due to climate change-driven drought, and while this is partly true, over-exploitation contributed just as much if not more.
The first signs of desertification appeared as far back as 1958, but calls for regulation failed. The resulting lack of arable land and food is a major cause of the country’s now decade-long civil war, says Gianluca Serra, ecologist and conservationist who worked with the UN to rehabilitate the Syrian steppes.
“Ninety-five percent of the [arable] land is in the process of desertification,” says Sarah Toumi, President and founder of Acacies for All, a social enterprise aiming to slow Tunisia’s creeping deserts.
The government has been doing the same since 1990 through reforestation, wind brakes and biological sand dune fixation, but efforts have been largely ineffective. As is often the case, land overexploitation is the core of the problem.
The issue is high-intensity modern farming, and a lack of incentive to let the land rest. But how do we tell people in a country with social tensions, high unemployment and an underperforming economy to sacrifice yields?
Land overexploitation and climate change are accelerating the process of desertification to the point where subsistence farmers are being displaced within their lifetimes. Geological change fast enough for humans to notice is extremely fast on geological scales, so there is reason to be worried.
However, we know what the causes are, and there are methods to address it. These will vary from place to place, but it generally involves changing agricultural practices and creating green barriers with the right species.
Generally speaking, we attempt to maximize agricultural yields to the expense of soil health. Worse, overproduction drives prices down, meaning farmers have to continue doing so in order to make ends meet, creating a vicious cycle. The only option is for the government to step in and regulate practices nation-wide so no farmer is left behind.
This article was written by Owen Mulhern.
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