The world has lost a third of its arable land due to erosion or pollution in the past 40 years, with potentially disastrous consequences as global demand for food soars, scientists have warned. New research has calculated that nearly 33 per cent of the world’s adequate or high-quality food-producing land has been lost at a rate that far outstrips the pace of natural processes to replace diminished soil. The University of Sheffield’s Grantham Centre for Sustainable Futures, which undertook the study by analysing various pieces of research published over the past decade, said the loss was catastrophic and the trend close to being irretrievable without major changes to agricultural practices. The continual ploughing of fields, combined with heavy use of fertilizers, has degraded soils across the world, the research found, with erosion occurring at a pace of up to 100 times greater than the rate of soil formation. It takes around 500 years for just 2.5cm of topsoil to be created amid unimpeded ecological changes. “You think of the dust bowl of the 1930s in North America and then you realise we are moving towards that situation if we don’t do something,” said Duncan Cameron, professor of plant and soil biology at the University of Sheffield. “We are increasing the rate of loss and we are reducing soils to their bare mineral components,” he said. “We are creating soils that aren’t fit for anything except for holding a plant up.”

More than six thousand years ago, the most advanced civilisation on planet was Sumer, rulers of the fertile plains of ancient Mesopotamia in modern day Iraq. The Sumerians weren’t powerful from their military strength or political system; rather, it was agriculture that developed their civilisation. Quite simply, the ancient Sumerians had developed techniques to produce far more agriculture than they could possibly consume.

This food surplus meant that they could build up a large pool of savings to be used in trade, or to feed workers who could pursue other careers like science and architecture. Nearly every great civilization ever since has shared the same characteristics being able to produce more than it consumes. In fact, no society can survive without the ability to feed itself. We’ve seen this throughout history. When the Sumerians complex, centrally-planned network of canals failed to adequately irrigate their farmland, the civilization quickly declined. The Roman Empire was notorious for routinely invading other lands looking to secure additional sources of food. During the American Civil War, a large part of the Union’s strategy was to cut off the South from its food sources, and burn to the ground every acre of farmland they could find. And despite decades of economic hardship, the French Revolution finally kicked off in 1789 because the nation could no longer feed itself…and people were starving. Early on in US history, the country’s strength came from this same ability to produce more than it consumed.

It is alarming for Bangladesh that arable land across the country is briskly disappearing in the current times. Growing industrialisation, rapid urbanisation and mindless encroachment of human habitat have quickened the process. According to World Bank data, 66.1 percent of the total area of Bangladesh was farmland back in 1961, which stood 58.92 percent in 2014. Bangladesh Bureau of Statistics, in its recent report, has also mentioned that the arable land in the country is fast depleting by around 40 thousand hectares each year due to non-farm purposes, meaning there would be literally no farmland after 50 years from here on. The country will subsequently lose food security, making its people entirely exposed to volatile international food market. In search for farmlands for the country’s rising population, forests would be diminished which now roughly stands 11 percent of the total area and water bodies would be filled in as a consequence, implicating an irreparable damage to environment and nature, which might more frequently cause natural calamities like flood, draught, cyclone, landslide. Huge number of people would turn into climate refugees causing strained relations with its neighbour countries. Therefore, a solution to the critical issue of farmland depletion could be formulation of an erudite and pragmatic land-use policy. Notably enough, the 2009 parliamentary standing committee on agriculture suggested for a stringent law to completely stop the use of agricultural lands in non-farm activities.

The government should no longer delay and hesitate in enacting the law in this respect. The horizontal expansion of residences, schools-colleges, factories, industries and the like should be minimised while these may be encouraged to go vertical. The high population growth rate should be checked. Farmers, on the other hand, should be discouraged from the overuse of fertilisers and insecticides in soil, for these chemicals may loosen the soil compaction to quicken erosion. An inclusive effort from all quarters of the country can prevent the farmlands from diminishing any further.Some 2,096 bighas of farmland and water bodies were lost to non-agricultural uses a day in the decade since 2003, a study revealed recently. Almost 80 percent of the lost lands were converted into homesteads, a team led by Abul Barkat, economics professor at Dhaka University, found. The second largest chunk,17.4 percent, was eaten up for the construction of schools, clinics, mosques and roads, taking the vital resource away from food production. The survey titled “Increasing commercialisation of agricultural land and contract farming in Bangladesh: an alternative appraisal” covered 990 households in 11 districts. The level of agricultural commercialisation was high in Cox’s Bazar, Kushtia and Manikganj districts followed by Rajshahi, Natore, Rangamati and Habiganj and was low in the remaining four districts studied. The commercialisation of agriculture in Bangladesh started after the introduction of green revolution in the 1960s, which accelerated in the ‘80s and 90s, the study found.

Agricultural commercialisation increased the rate of transfer of lands from the poor and marginalised people to the rich and upper middle classes, and changed crop production patterns, Barkat said. In course of agricultural commercialisation, the livelihood opportunities for the poor and marginalised rural households are further constrained due to their lack of access to traditional resources, he said, citing that nearly one-fifth of the studied households lost cropland. Commercialisation in agriculture increases landlessness and pauperisation, and makes food security of the poor uncertain, Barkat said, adding: Food adulteration is an inevitable outcome of commercial food production. Even more alarming is the extensive application of green revolution technologies, which are continuously hurting soil fertility, he said. Prof Barkat recommended imposing high tax on tobacco companies, stopping tobacco cultivation in government and forest lands and controlling shrimp farming. He also suggested formula ting a policy to prevent grabbing and unplanned use of land Delays in framing the land use law indicate that the government has shelved the plan, said Syeda Rizwana Hasan, chief executive of Bangladesh Environmental Lawyers Association. The erosion of soil has largely occurred due to the loss of structure by continual disturbance for crop planting and harvesting. If soil is repeatedly turned over, it is exposed to oxygen and its carbon is released into the atmosphere causing it to fail to bind as effectively.

This loss of integrity impacts soil’s ability to store water, which neutralizes its role as a buffer to floods and a fruitful base for plants. Degraded soils are also vulnerable to being washed away by weather events fueled by global warming. Deforestation, which removes trees that help knit landscapes together, is also detrimental to soil health. The steep decline in soil has occurred at a time when the world’s demand for food is rapidly increasing. It’s estimated the world will need to grow 50% more food by 2050 to feed an anticipated population of 9 billion people.

According to the UN’s Food and Agriculture Organisation, the increase in food production will be most needed in developing countries. The academics behind the University of Sheffield study propose a number of remedies to soil loss, including recycling nutrients from sewerage, using biotechnology to wean plants off their dependence upon fertilizers, and rotating crops with livestock areas to relieve pressure on arable land.Around 30% of the world’s ice-free surfaces are used to keep chicken, cattle, pigs and other livestock, rather than to grow crops. We need a radical solution, which is to re-engineer our agricultural system, Cameron said. We need to take land out of production for a long time to allow soil carbon to rebuild and become stable. We already have lots of land it’s being used for pasture by the meat and dairy industries. Rather than keep it separated, we need to bring it into rotation, so that that there is more land in the system and less is being used at any one time.

The writer is a freelancer.

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