10 May 2016 Current Affairs: The new tally is part of a report carried out by the Royal Botanic Gardens, Kew. It is its first global assessment of the world's flora.The study also found that 2,034 new plant species were discovered in 2015.
However, the report warns that 21% of plants are at risk of extinction, with threats including climate change, habitat loss, disease and invasive species.
The researchers came up with their new plant total by searching through existing databases.However, they found a lot of overlap within these records, with some plants being given different names by different botanists at different times.
In total, they now estimate that, excluding algae, mosses, liverworts and hornworts, there are 390,900 plants, of which approximately 369,400 are flowering.
Last year's discoveries include a tree called Gilbertiodendron maximum, which grows up to 45m-high, found in the forests of Gabon in West Africa.Ninety new species of Begonia were also uncovered, as were five new species of onion and a sprawling, insect-eating plant called Drosera magnifica in Brazil, which was first spotted on Facebook.Botanists from China, Australia and Brazil were the most likely to find and name new plants.
With the damage they cause to the environment and the difficulty and expense of removing them, the report says the global cost of invasive species is estimated at nearly 5% of the world's economy.The conservationists have now logged 4,979 invasive species around the world.
The report also found that more than 10% of the parts of the Earth that are covered with vegetation are highly sensitive to climate change. However the longer-term effects were not yet clear.
Kew's global assessment will now be carried out annually, allowing scientists to monitor how plants are changing over time.