Deforestation
In 2019, nearly a third of the overall tree cover loss occurred within humid tropical primary forests. These areas are mature rainforests that hold immense value for biodiversity and carbon storage. The direct cause of most deforestation is agriculture by far. More than 80% of deforestation was attributed to agriculture in 2012. Forests are being converted to plantations for coffee, palm oil, rubber and various other popular products. Livestock grazing also drives deforestation. Further drivers include the wood industry, urbanization and mining. The effects of climate change act as another cause via increased risk of wildfires.
Scientists state that tropical deforestation releases 1.5 billion tons of carbon each year into the atmosphere. A 2022 study shows annual carbon emissions from tropical deforestation have doubled during the last two decades. Deforestation reduces the content of water in the soil and groundwater as well as atmospheric moisture. When part of a forest is removed, trees no longer transpire this water, resulting in a much drier climate. Shrinking forest cover lessens the landscape's capacity to intercept precipitation. Instead of trapping precipitation, which then percolates to groundwater systems, deforested areas become sources of surface water runoff. That quicker transport of surface water can translate into flash flooding and more localized floods than would occur with forest cover.
Rates of deforestation sharply accelerated around 1852. As of 1947, the planet had vast amounts of mature tropical forests, but by 2015, it was estimated that about half of these had been destroyed. Total land coverage by tropical rainforests decreased from 14% to 6%. Much of this loss happened between 1960 and 1990, when 20% of all tropical rainforests were destroyed. In the early 2000s, some scientists predicted that unless significant measures are taken on a worldwide basis, by 2030 there will only be 10% remaining. The first evidence of deforestation appears in the Mesolithic period. It was probably used to convert closed forests into more open ecosystems favourable to game animals. Widespread decrease in elm pollen across Europe between 8400 and 8300 BC may represent land clearing by fire at the onset of Neolithic agriculture.
Up to 90% of West Africa's coastal rainforests have disappeared since 1900. Madagascar has lost 90% of its eastern rainforests. In South Asia, about 88% of the rainforests have been lost. Mexico, India, the Philippines, Indonesia, Thailand, Burma, Malaysia, Bangladesh, China, Sri Lanka, Laos, Nigeria, the Democratic Republic of the Congo, Liberia, Guinea, Ghana and the Ivory Coast, have lost large areas of their rainforest. Some 80% of the deforestation of the Amazon can be attributed to cattle ranching, as Brazil is the largest exporter of beef in the world. The regions with the highest tropical deforestation rate between 2000 and 2005 were Central America, which lost 1.3% of its forests each year, and tropical Asia. In Central America, two-thirds of lowland tropical forests have been turned into pasture since 1950.
In Kenya, deforestation has led to an increase in malaria cases which is now the leading cause of morbidity and mortality the country. A 2017 study found that deforestation substantially increased the incidence of malaria in Nigeria. Forest-associated diseases include malaria, Chagas disease, African trypanosomiasis, leishmaniasis, Lyme disease, HIV and Ebola. The majority of new infectious diseases affecting humans are zoonotic and their emergence may be linked to habitat loss due to forest area change. In Malaysia, thousands of acres of forest have been cleared for pig farms. This has resulted in an increase in the spread of the Nipah virus. According to the World Economic Forum, 31% of emerging diseases are linked to deforestation.
In 2014, about 40 countries signed the New York Declaration on Forests, a voluntary pledge to halve deforestation by 2020 and end it by 2030. The agreement was not legally binding, however, and some key countries did not sign onto it. As a result, the effort failed, and deforestation increased from 2014 to 2020. In November 2021, 141 countries agreed at the COP26 climate summit in Glasgow to the Glasgow Leaders' Declaration on Forests and Land Use. The agreement was accompanied by about $19.2 billion in associated funding commitments. In 2022 the European parliament approved a bill aiming to stop the import linked with deforestation. This EU Regulation on Deforestation-free products requires companies who want to import certain types of products to prove the production is not linked to areas deforested after the 31st of December 2020.
Common questions
What percentage of tree cover loss occurred in humid tropical primary forests in 2019?
Nearly a third of the overall tree cover loss occurred within humid tropical primary forests in 2019. These areas are mature rainforests that hold immense value for biodiversity and carbon storage.
How much carbon does tropical deforestation release into the atmosphere each year according to scientists?
Scientists state that tropical deforestation releases 1.5 billion tons of carbon each year into the atmosphere. A 2022 study shows annual carbon emissions from tropical deforestation have doubled during the last two decades.
When did rates of deforestation sharply accelerate and what was the total land coverage by tropical rainforests before this period?
Rates of deforestation sharply accelerated around 1852. Total land coverage by tropical rainforests decreased from 14% to 6% as the process continued through the modern era.
Which countries have lost large areas of their rainforest including West Africa, Madagascar, and South Asia?
Up to 90% of West Africa's coastal rainforests have disappeared since 1900 and Madagascar has lost 90% of its eastern rainforests. In South Asia, about 88% of the rainforests have been lost while Mexico, India, the Philippines, Indonesia, Thailand, Burma, Malaysia, Bangladesh, China, Sri Lanka, Laos, Nigeria, the Democratic Republic of the Congo, Liberia, Guinea, Ghana and the Ivory Coast have also lost large areas of their rainforest.
What percentage of emerging diseases are linked to deforestation according to the World Economic Forum?
According to the World Economic Forum, 31% of emerging diseases are linked to deforestation. The majority of new infectious diseases affecting humans are zoonotic and their emergence may be linked to habitat loss due to forest area change.
When did 141 countries agree at the COP26 climate summit in Glasgow to the Glasgow Leaders Declaration on Forests and Land Use?
In November 2021, 141 countries agreed at the COP26 climate summit in Glasgow to the Glasgow Leaders' Declaration on Forests and Land Use. The agreement was accompanied by about $19.2 billion in associated funding commitments.