Around 30% of tree species around the world are threatened with extinction, and at least 142 of them are recorded as extinct in the wild, according to the State of the World’s Trees report, which was released by Botanic Gardens Conservation International (BGCI) on Wednesday.
According to the landmark report by the plant conservation charity organisation based in London, the main threats to tree species around the world are forest clearance and other forms of habitat loss, direct exploitation for timber and other products, the spread of invasive pests and diseases, livestock farming and residential & commercial development. Climate change is also having a “clearly measurable” impact, the report adds.
“Through the Global Tree Assessment, intensive research has been undertaken over the past five years to compile extinction risk information on the 58,497 tree species worldwide. We now know that 30% of tree species are threatened with extinction and at least 142 tree species are recorded as extinct,” the report explains.
Overall the number of threatened tree species is double the number of threatened mammals, birds, amphibians and reptiles combined, a Reuters story on the BGCI report explains. “This report is a wake up call to everyone around the world that trees need help,” BGCI Secretary General Paul Smith said in a statement in the Reuters report.
The report explains that habitat loss is currently the greatest threat to tree species: this includes the total removal of vegetation, as well as degradation and fragmentation of persisting habitats. “Over the past three hundred years, global forest area has decreased by about 40% and 29 countries have lost more than 90% of their forest cover,” the BGCI report highlights.
The largest number of tree species is in the Neotropics (Central and South America) with 23,631 tree species, followed by the other tropical regions: Indo-Malaya (tropical Asia) (13,739 species) and the Afrotropics (Africa south of the Sahara, including Madagascar) (9,237 species). The Nearctic (North America) and Oceania are the two regions with the lowest number of tree species, the BGCI report adds. While trees can play a crucial role in the fight against the climate crisis, the report explains that they are also important indicators of the health of an ecosystem.
The highest proportion of threatened species is found in tropical Africa, which includes Madagascar, which is also one of the countries with the highest level of threatened trees. Temperate zones of Europe, Asia and North America, the BGCI report explains, which have relatively low tree diversity also have the lowest proportion of tree species which are threatened with extinction. The larger mega-diverse countries -- like Brazil, China, Colombia, Indonesia, etc. -- have a large number of tree species and also a large number of threatened species.
Among the most at-risk trees are species including magnolias and dipterocarps -- which are commonly found in Southeast Asian rainforests, the Reuters report explains. Oak trees, maple trees and ebonies also face threats. The extinction of a single tree species could prompt the loss of many others, the report adds.
According to the tree statistics mentioned in the report, India has 2,603 tree species, of which 650 are endemic. Some 469 tree species in India are threatened, which is approximately 18% of the total number of species in the country.