More tree species than thought: 9000 unknown

Species diversity More than thought: around 9,000 tree species still await discovery

The number of tree species on earth is probably much greater than previously thought. According to a recent study, there are around 73.000 species of trees – 9200 of which have not even been discovered and described yet. Until now, experts assumed that there were around 60.000 tree species worldwide from.

About one-third of the undiscovered species are thought to be very rare and spatially restricted, the international team of scientists reports in the Proceedings of the US National Academy of Sciences ("PNAS"). Especially these rare species would be vulnerable to human interference with nature, such as climate change or deforestation.

Trees are not in themselves small or fundamentally rare creatures that are easy to overlook, write the scientists led by Roberto Cazzolla Gatti of Purdue University (USA) in their article. Nevertheless, basic information about the number of species on the planet was missing. To expand knowledge, the researchers combined data sets on the worldwide occurrence and frequency of trees for their study.

Utah: Why the world's largest creature is slowly dying - and how it could be saved

Utah Why the world’s largest creature is slowly dying – and how it could be saved

"We have combined the individual data sets into a huge global data set", Jingjing Liang of Purdue University explains. Every data set is created when someone measures the individual trees in a forest and collects information about species, size and other characteristics. "Counting the number of tree species worldwide is like a puzzle with pieces spread all over the world."

In the end, the combined data set included a total of 64,100 tree species. That’s close to the results of an earlier study that came up with about 60,000 tree species worldwide, he says. To estimate the number of previously undiscovered species in a region, the researchers used statistical methods, primarily so-called species accumulation curves. These curves indicate – in simple terms – how many species are discovered in a given region and area at what collection effort. Roughly speaking, more species are found initially, the longer one searches. After some time, however, the rise of the curve flattens out.

Trees and forests have a wide range of benefits for people

The researchers arrived at a total number of 73.300 tree species – and thus to about 9200 still undiscovered species. About 40 percent of these grow in South America, according to the study. Most rare species are also found there (8200) and most endemic species – i.e. species that only grow there. There is also a high number of rare species in Eurasia (6100) and Africa (3900). Most species are found in tropical and subtropical humid forests – and that’s where most of the still unknown species are likely to be discovered, researchers suspect.

Natural wonder Silent giants: The fabulous world of trees

"Extensive knowledge of the richness and diversity of trees is key to maintaining the stability and functioning of ecosystems", says Gatti. In this context, the researchers point to the many benefits of trees and forests for humans: they provide building materials and fuel, clean the air, slow climate change, protect against erosion and flooding and, last but not least, offer numerous opportunities for recreation, such as hiking, hunting or camping.

Like this post? Please share to your friends:
Leave a Reply

;-) :| :x :twisted: :smile: :shock: :sad: :roll: :razz: :oops: :o :mrgreen: :lol: :idea: :grin: :evil: :cry: :cool: :arrow: :???: :?: :!: