According to UNCCD, land degradation is “the reduction or loss of the biological or economic productivity and complexity of rainfed cropland, irrigated cropland, or range, pasture, forest and woodlands resulting from a combination of pressures, including land use and management practices”.
Land degradation is undermining Earth’s capacity to sustain humanity, and failure to reverse it will pose challenges for generations to come, a new United Nations report found.
A million sq km of land is getting degraded each year, with an estimated 15 million sq km already impacted — more than the entire continent of Antarctica — by land degradation, the report titled Stepping back from the precipice: Transforming land management to stay within planetary boundaries said.
The analysis has been carried out by the United Nations Convention to Combat Desertification (UNCCD) — a legally binding framework to address desertification and the effects of drought — in collaboration with Germany’s Potsdam Institute for Climate Impact Research. It was published on Monday, a day before the 16th session of the Conference of the Parties (COP16) of UNCCD began in Riyadh, Saudi Arabia.
What is land degradation? Why is it a matter of concern?
According to UNCCD, land degradation is “the reduction or loss of the biological or economic productivity and complexity of rainfed cropland, irrigated cropland, or range, pasture, forest and woodlands resulting from a combination of pressures, including land use and management practices”.
Land degradation adversely affects humans and ecosystems around the planet. For instance, it raises the risk of malnutrition by reducing the quality and quantity of food production. It contributes to the spread of water- and food-borne diseases that result from poor hygiene and scarcity of clean water. It can cause respiratory diseases due to soil erosion. Marine and freshwater systems also suffer due to land degradation. For example, eroded soil carrying fertilisers and pesticides washes into water bodies, harming both the fauna living there and local communities which depend on them.
Land degradation contributes to climate change as well. The world’s soil is the largest terrestrial carbon sink. When land is degraded, soil carbon can be released into the atmosphere, along with nitrous oxide. This can further exacerbate global warming.
The new report said land degradation has reduced the capacity of land ecosystems such as trees and soil to absorb human-caused carbon dioxide by 20% in the last decade. Previously, these ecosystems could absorb nearly one-third of this kind of pollution.
What is causing land degradation?
Unsustainable agricultural practices such as the heavy use of chemical inputs, pesticides, and water diversion are the foremost drivers of land degradation, the report said. That is because such practices lead to deforestation, soil erosion, and pollution.
“Unsustainable irrigation practices deplete freshwater resources, while excessive use of nitrogen- and phosphorus-based fertilisers destabilise ecosystems,” according to the report.
Another factor is climate change — land degradation not only contributes to climate change but is also spurred by it. A report by the Intergovernmental Panel on Climate Change (IPCC), the UN body for assessing the science related to climate change, noted that global warming has worsened land degradation by increasing frequency, intensity and/ or amount of heavy precipitation, and increased heat stress.
Then there is rapid urbanisation, which has intensified land degradation by contributing to habitat destruction, pollution, and biodiversity loss.
Which areas are the worst affected?
The report has identified several land degradation hotspots in dry regions such as South Asia, northern China, the High Plains and California in the United States, and the Mediterranean. A third of humanity now lives in drylands, which include three-quarters of Africa. It also noted that land degradation hits low-income countries disproportionately. That is because its impacts are concentrated in tropical and arid regions, and poorer countries have lesser resilience to withstand land degradation and its fallouts.
Written by Alind Chauhan
Source: Indian Express, 3/12/24
