Tropical forests in Africa's mountains store more carbon than previously thought - but are disappearing fast

Date:
August 25, 2021
Source:
University of York
Summary:
An international study found that intact tropical mountain (or
montane) forests in Africa store around 150 tons of carbon per
hectare. This means that keeping a hectare of forest standing saves
CO2 emissions equivalent to powering 100 homes with electricity
for one year.



FULL STORY ========================================================================== Scientists studying tropical forests in Africa's mountains were surprised
to uncover how much carbon they store, and how fast some of these forests
are being cleared.


==========================================================================
The international study reported today in Nature, found that intact
tropical mountain (or montane) forests in Africa store around 150
tonnes of carbon per hectare. This means that keeping a hectare of
forest standing saves CO2 emissions equivalent to powering 100 homes
with electricity for one year.

The study found that African mountain forests store more carbon per unit
area than the Amazon rainforest and are similar in structure to lowland
forests in Africa. Existing guidelines for African mountain forests --
which assume 89 tonnes of carbon per hectare -- greatly underestimate
their role in global climate regulation.

The international team also investigated how much tropical mountain
forest had been lost from the African continent in the past 20 years. They found that 0.8 million hectares have been lost, mostly in the Democratic Republic of the Congo, Uganda and Ethiopia, emitting over 450 million
tonnes of CO2 into the atmosphere. If current deforestation rates
continue, a further 0.5 million hectares of these forests would be lost
by 2030.

Lead author Dr Aida Cuni-Sanchez, from the University of York's Department
of Environment and Geography and at Norwegian University of Life Sciences, said: "The results are surprising because the climate in mountains would
be expected to lead to low carbon forests.

"The lower temperatures of mountains and the long periods they are covered
by clouds should slow tree growth, while strong winds and steep unstable
slopes might limit how big trees can get before they fall over and die.



==========================================================================
"But unlike other continents, in Africa we found the same carbon store per
unit area in lowland and mountain forests. Contrary to what we expected,
large trees remain abundant in mountain forests, and these large trees
(defined as having diameters over 70 cm) store a lot of carbon."
Scientists measured 72,000 trees in 44 mountain sites in 12 African
countries, from Guinea to Ethiopia, and south to Mozambique. In each
mountain site they established plots where they recorded the diameter,
height and species of every tree.

Researchers said that better knowledge about how much carbon mountain
forests store is especially important for the ten African nations where
the only tropical forests they have are those found on mountains.

"While we know what makes African forests special, we don't yet know
why they are different. It is possible that in Africa, the presence of
large herbivores such as elephants plays an important role in mountain
forest ecology, as these large animals disperse seeds and nutrients,
and eat small trees creating space for others to grow larger, but this
requires further investigation," Dr Cuni- Sanchez added.

Co-author Dr Phil Platts, from York's Department of Environment and
Geography and the IUCN's Climate Change Specialist Group, said: "About
five per cent of Africa's tropical mountain forests have been cleared
since 2000, and in some countries the rate exceeds 20 per cent. Besides
their importance for climate regulation, these forests are habitats for
many rare and endangered species, and they provide very important water services to millions of people downstream." Most African nations have committed large amounts of land to forest restoration under the Bonn
Challenge. Although forest restoration is important to mitigate climate
change, avoiding deforestation is a greater priority.

Co-author Dr Martin Sullivan, at the Department of Natural Sciences,
Manchester Metropolitan University, added: "Previous carbon estimates
for tropical mountain forests in Africa were much lower than the values
we report in our study.

"We hope that these new data will encourage carbon finance mechanisms
towards avoided deforestation in tropical mountains. As outlined in the
Paris Agreement, reducing tropical deforestation in both lowland and
mountain forests must be a priority." Co-author Dr Gerard Imani,
at the Department of Biology, Universite' Oficielle de Bukavu
in DR Congo, added: "Carbon finance mechanisms could help improve
conservation interventions on the ground -- even within protected areas, deforestation, forest degradation and defaunation remain a challenge." ========================================================================== Story Source: Materials provided by University_of_York. Note: Content
may be edited for style and length.


========================================================================== Journal Reference:
1. Aida Cuni-Sanchez, Martin J. P. Sullivan, Philip J. Platts, Simon L.

Lewis, Rob Marchant, Ge'rard Imani, Wannes Hubau, Iveren Abiem, Hari
Adhikari, Tomas Albrecht, Jan Altman, Christian Amani, Abreham B.

Aneseyee, Valerio Avitabile, Lindsay Banin, Rodrigue Batumike,
Marijn Bauters, Hans Beeckman, Serge K. Begne, Amy C. Bennett,
Robert Bitariho, Pascal Boeckx, Jan Bogaert, Achim Bra"uning,
Franklin Bulonvu, Neil D.

Burgess, Kim Calders, Colin Chapman, Hazel Chapman, James
Comiskey, Thales de Haulleville, Mathieu Decuyper, Ben DeVries,
Jiri Dolezal, Vincent Droissart, Corneille Ewango, Senbeta Feyera,
Aster Gebrekirstos, Roy Gereau, Martin Gilpin, Dismas Hakizimana,
Jefferson Hall, Alan Hamilton, Olivier Hardy, Terese Hart, Janne
Heiskanen, Andreas Hemp, Martin Herold, Ulrike Hiltner, David
Horak, Marie-Noel Kamdem, Charles Kayijamahe, David Kenfack,
Mwangi J. Kinyanjui, Julia Klein, Janvier Lisingo, Jon Lovett,
Mark Lung, Jean-Remy Makana, Yadvinder Malhi, Andrew Marshall,
Emanuel H. Martin, Edward T. A. Mitchard, Alexandra Morel, John
T. Mukendi, Tom Muller, Felix Nchu, Brigitte Nyirambangutse, Joseph
Okello, Kelvin S.-H. Peh, Petri Pellikka, Oliver L. Phillips, Andrew
Plumptre, Lan Qie, Francesco Rovero, Moses N. Sainge, Christine B.

Schmitt, Ondrej Sedlacek, Alain S. K. Ngute, Douglas Sheil, Demisse
Sheleme, Tibebu Y. Simegn, Murielle Simo-Droissart, Bonaventure
Sonke', Teshome Soromessa, Terry Sunderland, Miroslav Svoboda,
Hermann Taedoumg, James Taplin, David Taylor, Sean C. Thomas,
Jonathan Timberlake, Darlington Tuagben, Peter Umunay, Eustrate
Uzabaho, Hans Verbeeck, Jason Vleminckx, Go"ran Wallin, Charlotte
Wheeler, Simon Willcock, John T.

Woods, Etienne Zibera. High aboveground carbon stock of African
tropical montane forests. Nature, 2021; 596 (7873): 536 DOI:
10.1038/s41586-021- 03728-4 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/08/210825113706.htm

--- up 15 weeks, 5 days, 22 hours, 45 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)