The baobab tree ( Adansonia ), also known as the “Tree of Life” , has an appearance that is difficult to forget. It is found in the savanna regions of Africa, Madagascar, and Australia. The trees form a very thick and wide trunk and can be thousands of years old and develop such large holes inside, such huge cavities that there is even one that houses a bar inside (Sunland Baobab).
But the aforementioned tree, the more than 1,000-year-old Sunland baobab , apparently the largest tree in Africa, was “collapsed” last year. Another famous baobab, the Chapman tree in Botswana, also collapsed in 2016.
As a new scientific study published in Nature Plants suggests, something similar is happening to the world’s oldest and largest baobabs in “an event of unprecedented magnitude.”
The study, conducted by Adrian Patrut from Babes-Bolyai University (Romania) and an international group of experts, concluded that in the last 12 years, “9 of the 13 oldest trees and 5 of the 6 largest have died , or at least its oldest parts; the stems collapsed and died “, state the authors.
We speak of a tragic loss , taking into account the history and culture associated with these trees, which are also a key source of food for humans. The baobab “is famous because it is the largest angiosperm, and it is the most emblematic tree in Africa,” explains Patrut.
A unique structure
Researchers have been examining trees since 2005 and have developed a theory of how they grow, while documenting these irreparable losses to nature.
The key is that the largest baobabs weave multiple tree stems around a small “false cavity” , and this is what gives them their unique structure. These stems can also grow together, leading to an odd feature where, growing outward from the center of the cavity, the wood can age for a time, rather than younger, as might normally be expected.
“This is a unique feature of the African baobab and all baobab trees,” said Patrut, who has dated different parts of the trees using radiocarbon dating methods.
The authors claim that the largest trees are the most vulnerable, blaming climate change as a possible culprit , although the study itself says “more research is needed to support or refute this assumption.”
“Larger trees need more water and nutrients than smaller trees, and they are the most affected by the increase in temperature and drought,” explains Patrut.
This study rules out, at least for the oldest trees, that their deaths were caused by an epidemic of a fungus or the like.
The deaths are “an important modification in the ecosystem and the integrity of biodiversity,” the researcher says.
Reference: The demise of the largest and oldest African baobabs. Adrian Patrut, Stephan Woodborne, Roxana T. Patrut, Laszlo Rakosy, Daniel A. Lowy, Grant Hall & Karl F. von Reden. Nature Plants (2018) DOI: https://doi.org/10.1038/s41477-018-0170-5
