[PCA] World Reforestation Potential - the prospects and problems

[De Angelis, Patricia]

Series of articles discussing forests and restoration illustrating interesting prospects and disagreement among experts...

***Mapping tree density at a global scale
By T. W. Crowther, H. B. Glick, et al.
Nature 525:201–205
2015

ABSTRACT: The global extent and distribution of forest trees is central to our understanding of the terrestrial biosphere. We provide the first spatially continuous map of forest tree density at a global scale. This map reveals that the global number of trees is approximately 3.04 trillion, an order of magnitude higher than the previous estimate. Of these trees, approximately 1.30 trillion exist in tropical and subtropical forests, with 0.74 trillion in boreal regions and 0.66 trillion in temperate regions. Biome-level trends in tree density demonstrate the importance of climate and topography in controlling local tree densities at finer scales, as well as the overwhelming effect of humans across most of the world. Based on our projected tree densities, we estimate that over 15 billion trees are cut down each year, and the global number of trees has fallen by approximately 46% since the start of human civilization.

More: https://www.nature.com/articles/nature14967

***Report--Global Tree Restoration Potential
By Jean-Francois Bastin, Yelena Finegold, Claude Garcia, Danilo Mollicone, Marcelo Rezende, Devin Routh, Constantin M. Zohner, Thomas W. Crowther
Science 365(6448):76-79
Jul 2019

The potential for global forest cover

The restoration of forested land at a global scale could help capture atmospheric carbon and mitigate climate change. Bastin et al. used direct measurements of forest cover to generate a model of forest restoration potential across the globe (see the Perspective by Chazdon and Brancalion). Their spatially explicit maps show how much additional tree cover could exist outside of existing forests and agricultural and urban land. Ecosystems could support an additional 0.9 billion hectares of continuous forest. This would represent a greater than 25% increase in forested area, including more than 200 gigatonnes of additional carbon at maturity.Such a change has the potential to store an equivalent of 25% of the current atmospheric carbon pool.

More: https://science.sciencemag.org/content/365/6448/76

***News & Opinion--Researchers Find Flaws in High-Profile Study on Trees and Climate
By Katarina Zimmer
The Scientist
Oct 17, 2019

In July, a high-profile study in Science estimated that Earth has space for another 0.9 billion hectares’ worth of trees—an area the size of the continental US. Simply allowing forests to recover in those areas would suck more than 200 gigatons of carbon out of the atmosphere, a significant chunk of what humans have emitted in the last century. “Global tree restoration is our most effective climate change solution to date,” the authors claimed in the paper.

Now, four independent groups take issue with the study’s methodology. Although reforestation remains a powerful tool in tackling climate change, the authors overstated the number of trees that could feasibly grow under Earth’s current climate, and how much carbon they could pull out of the air, according to the critiques published today (October 17) in Science. The authors respond to each criticism in an accompanying response, insisting that their estimates are accurate.

Full article: <https://science.sciencemag.org/content/365/6448/76>
https://www.the-scientist.com/news-opinion/researchers-find-flaws-in-high-profile-study-on-trees-and-climate--66587

***The audacious effort to reforest the planet
By Ben Guarino
The Washington Post
Jan. 22, 2020

At age 9, Felix Finkbeiner planted his first tree.He had just learned about Wangari Maathai, a Kenyan woman who won the Nobel Peace Prize for leading an effort to plant 30 million trees in Africa. The boy was struck by her message — that trees are powerful allies in the fight to curb global warming.

https://www.washingtonpost.com/graphics/2020/climate-solutions/trillion-tree-reforestation-climate-change-philippines/


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.plantconservation.org/pipermail/native-plants_lists.plantconservation.org/attachments/20200428/e1d6f58d/attachment.html>