Authors: Al Gore
The addition of rhizobium bacteria and mycorrhizal fungi to soils as seeds are planted can improve crop yields and also speed the recovery of
soil fertility and enhance the sequestration of soil carbon. The planting of leguminous trees every thirty feet or so as buffer strips and contour hedges can replenish nitrogen in the
soil and further protect against erosion. Leaving the majority of crop residue—like corn stover—on the land during and after harvesting the crop can also restore the
fertility of the soil while diminishing erosion. The use of biochar (from sustainable sources) in a
carefully managed way can also improve yields and soil quality. The reduction of meat as a percentage of a healthy diet can relieve pressure on the Earth’s topsoil. And the expansion of small-scale organic gardens in countries with a surplus of arable land could potentially add significant volumes of fresh food to the world supply, as they did in Western countries
when Victory Gardens were planted during World War II.
But perhaps the single most effective measure to protect topsoil would be to use carbon credits to provide an additional source of income for farmers who pay careful attention to safeguarding and improving the carbon content and fertility of their soils.
So long as the world ignores the value of topsoil in its constant calculations of growth and productivity, the demands placed on agriculture by the combination of growing population and growing per capita consumption of food will continue putting the future of topsoil at severe risk. At current consumption rates (which are still increasing), we need an additional 15 million hectares each year to
keep up with the extra food production needed for the increasing population. Yet we are destroying and losing approximately 10 million hectares
(approximately 25 million acres) every year. At present, much of the additional cropland being developed results in deforestation—often in forest areas that have very thin topsoils that are quickly depleted by wind and water after the trees are gone. In addition, the more forestland that is converted to farmland, the more biodiversity is lost.
In some respects, the global topsoil crisis is an echo of what happened in the United States in the first third of the twentieth century when the first mass market tractors—pulling the more efficient plows that had been invented three quarters of a century earlier—broke the sod of erodible grasslands in the Midwest for crops; over the next three
decades the vulnerable topsoil was washed and blown away, creating the Dust Bowl of the 1930s. Less well known in the U.S. is the even larger tragedy experienced in Central Asia during the 1950s when the USSR plowed an enormous area of grassland—
mostly in Kazakhstan (1954)—and created their own Dust Bowl.
Another epic land-use catastrophe occurred in Central Asia in the 1960s, when the USSR embarked on a shortsighted plan to grow thirsty cotton crops in dryland areas of Uzbekistan and Turkmenistan. So much water was diverted from two rivers—the Amu Darya and the Syr Darya—that the world’s fourth largest inland sea, the
Aral Sea, almost completely disappeared. I visited the Aral Sea two decades ago and saw firsthand the tragedy that resulted for the people who used to depend on it.
My father’s generation was motivated by the U.S. soil erosion crisis to adopt new land management techniques. One of the great accomplishments of FDR’s New Deal was the massive program to reconvert
eroded land to grassland and a nationwide effort to fight soil erosion. I still remember my father teaching me when I was a young boy how to stop gullies before they began cutting deep into the soil, and how to recognize the richest soil—it’s black from all the organic carbon in the soil.
Modern-day dust storms are now once again increasing in size and frequency as drylands are being overgrazed and erodible soils are subjected to higher temperatures and stronger winds. “
Drylands are on the front line of the climate change challenges for the world,” said Luc Gnacadja, who heads the U.N. Convention to Combat Desertification. The U.N. Environment Programme reports that land degradation in drylands threatens the
way of life for an estimated one billion people in 100 countries. Desertification is taking a toll on topsoil and destroying arable cropland—particularly in regions of Africa north and south of the Sahara, throughout the Middle East, in Central Asia, and in large areas of China, where overgrazing, poor cultivation techniques, and urban sprawl are contributing significantly to the phenomenon.
In the U.S., in July of 2011, Phoenix, Arizona, was covered with dust when, in the words of the National Weather Service, “A very large and historic
dust storm moved through a large swatch of Arizona.” Although
these Southwestern U.S. dust storms, often called haboobs, are not new, Phoenix has had an
unusually large number of them in recent years—seven in 2011 alone.
The U.S. Geological Survey and UCLA conducted a study in 2011 that predicted “accelerated rates of dust emission from wind erosion” as a result of climate change in the Southwestern United States. Climate expert Joseph Romm has recommended use of the term “dust-bowlification” as a way of
describing what is in store for many regions of desertifying drylands.
Lester Brown, long one of the world’s leading environmental experts, points out that the two most significant desertifying areas now generating dust storms are in north-central China and in the areas of Central Africa that lie on the southern edge of the Sahara Desert. As Brown puts it, “Two huge dust bowls are forming, one across northwest
China, western Mongolia, and central Asia; the other in central Africa.”
According to geographer Andrew Goudie at Oxford, dust storms from the Sahara
have increased tenfold during the last fifty years. The chairman of the African Union, Jean Ping, says, “The phenomenon of desertification affects 43 percent of productive lands, or 70 percent of economic
activity and 40 percent of the continent’s population.” In large areas of Sub-Saharan Africa, soil carbon content is now lower than it was in the
United States’ Midwest just prior to the Dust Bowl.
In Nigeria, while human population increased fourfold over the last sixty years,
the number of livestock exploded from six million to more than 100 million. Partly as a result, the northern region of Nigeria is being desertified—which is contributing to growing clashes between
Muslims moving from the north into non-Muslim areas in southern Nigeria. Growth in the population of both humans and livestock is also driving competition for land in other drying areas of Africa and has led to deadly conflicts between herders and farmers (whose ethnicities and religions are also different), who have fought one another in Sudan, Mali, and elsewhere.
The same livestock population explosion is damaging the overgrazed grasslands
surrounding China’s Gobi Desert, where the dust storms are also increasing dramatically. While the United States and China have roughly the same amount of grazing land and roughly the same number of cattle (80–100 million), China has 284 million sheep and
goats compared
to less than 10 million in the United States. According to the latest statistics available,
China is now losing almost 1,400 square miles of arable land to deserts every year.
The U.S. embassy in China has used satellite photos to illustrate the “desert mergers and acquisitions” in north-central China where two deserts in
Inner Mongolia and Gansu Province are merging and expanding. In Xinjiang Province in northwestern China, the same thing is happening, as the
Taklamakan and Kumtag deserts are also merging and expanding. More than 24,000 villages and their surrounding cropland have had to be at least partially
abandoned in these northern and western regions of China. Similar tragedies are unfolding in both Iran and Afghanistan, both of which
have already abandoned many villages to the encroaching desert.
While the massive sandstorms in China and Africa are capturing attention today, Lester Brown warns, “A third massive cropland expansion is now taking place in the Brazilian Amazon Basin and in the cerrado,
a savannah-like region bordering the basin on its south side.” These soils are highly erodible and the results are predictable: low yields, followed by soil erosion on a massive scale. The knock-on effects also include the further expansion of cattle ranching into the
Amazon rainforest, adding even more risk to the integrity of that globally important ecosystem. The Amazon has already
suffered from two “hundred-year droughts” in the last seven years. As the deforestation and the wildfires continue in the Amazon, many experts have expressed concern that the Amazon is in danger of being transformed over time from the
greatest tropical rainforest on Earth into a massive dryland region.
With the rapidly increasing populations in Africa and the Middle East, and impending food shortages, it is remarkable that the world has paid so little attention to the desertification crisis. According to the U.N. Convention to Combat Desertification’s Luc Gnacadja, the reason desertification has not become a higher priority is that
90 percent of the people affected live in developing countries. It is another example of the imbalance of power in the world—and the lack of leadership. Gnacadja added, “
The top 20 centimeters of soil is all that stands between us and extinction.”
The loss of arable land is particularly acute in the most populated nation of North Africa. According to the United Nations, Egypt is now losing an incredible 3.5 acres per hour of its fertile agricultural land in
the Nile Delta—mainly because of new construction and urban sprawl
to accommodate additional shelter for Egypt’s fast growing population.
In addition, rising sea level in the Mediterranean is already pushing saltwater aquifers upward in areas near the coast,
resulting in the loss of cropland to salinization. Salinization is also occurring in the rich
Ganges Delta, the Mekong Delta, and in other so-called mega-deltas. A one-meter rise in sea level—less than that predicted during this century—would inundate a significant percentage of the most fertile soils in the Nile Delta—
from whence 40 percent of Egypt’s food production comes.
The pressure created by the increased use of water-intensive agriculture, population growth, and economic expansion is increasing tensions over the allocation of river water in several regions of the world where the management of rivers and dams affects watersheds shared by multiple countries. The potential for conflict is building in the Nile River watershed, where the largest country dependent on the Nile, Egypt, now benefits from its allocation of the majority of the Nile’s water. But Ethiopia, where 85 percent of the Nile’s headwaters originate but where very little of that water is now consumed, will double its population in the next thirty-seven years—and Sudan, which also depends on the Nile, is expected to
increase its population 85 percent during the same period.
To the east of Egypt, the decision by Turkey to take a larger portion of the headwaters from the Tigris and Euphrates has led to growing
complaints by Iraq and Syria that they are being treated unjustly. Both Iraq and Syria have been overdepleting their underground aquifers as they seek a resolution of the issue. Similarly, China’s effort to take for itself a larger percentage of water from rivers that flow into Southeast Asia and India is raising tensions that
will only get worse as populations in all the affected countries increase. In the United States, the growing conflicts over allocations of water in the West from the
Colorado River system are being waged in court. But the underlying cause in all four of these giant watersheds is the same: there’s more demand for water and less supply.
Conflicts between nations over access to freshwater have historically produced very few wars, though conflicts
within
nations over water have frequently produced social tensions and occasional violent clashes. By contrast, conflicts over land have, of course, frequently caused wars in the past.
In our new globalized economy, some nations with growing populations and shrinking resources of topsoil and water for agriculture are embarking on large-scale projects to purchase vast tracts of arable land in other countries—particularly in Africa, where an estimated one third of the world’s uncultivated arable land is found. The degree of control that African governments—and the elites that run many of them—have over property rights is much greater in many parts of Africa where tribal property rights predating the colonial era are too easily ignored.
China, India, the Republic of Korea, Saudi Arabia, and other countries, along with multinational corporations and even hedge funds investing money from U.S. universities, are buying up large amounts of land in Africa to produce wheat and other crops for their own consumption and for sale in global markets. “It’s a new colonialism, it’s like the scramble of Africa in [the] 19th century whereby our resources were exploited to develop the Western world,” said Makambo Lotorobo,
an official with a Kenyan NGO, Friends of Lake Turkana.
“
There is no doubt that this is not just about land, this is about water,” said Philip Woodhouse from the University of Manchester. Devlin Kuyek, a researcher with GRAIN, an NGO specializing in food and agriculture issues, added, “
Rich countries are eyeing Africa not just for a healthy return on capital, but also as an insurance policy.”
This has led to
an agricultural real estate boom in Africa. More than one third of
Liberia’s land, for example, has been sold to private investors. According to an analysis by the Rights and Resources Initiative, a Washington-based international coalition of NGOs, the Democratic Republic of the Congo has signed deals with foreign owners for 48.8 percent of its agricultural land; Mozambique has
signed deals with foreign growers for 21.1 percent of its land. Almost 10 percent of the land in South Sudan (according to Norwegian analysts)—and 25 percent of the best acreage around its capital—
was sold to investors after the country won its independence in 2011. China reached an agreement with the Democratic Republic of the Congo to
grow palm oil for biofuel on 2.8 million hectares of land. There is disagreement among experts on how much of the land involved in these massive African purchases is being used for biofuels. The World Bank calculated that in 2009, 21 percent were for
biofuels; the International Land Coalition
calculated that 44 percent was dedicated to biofuels.