Planting
trees is only a good news story if it’s done right
Bibi van
der Zee
In the
fight against global warming, we’d be better off preserving natural forests
than planting new monoculture plantations
@bibivanderzee
Wed 25 Dec
2019 10.00 GMTLast modified on Wed 25 Dec 2019 10.02 GMT
Afew years
ago I went to the Kilombero valley in Tanzania to find out why the elephants
there had disappeared. It was still beautiful; a long, green plain with red
earth, lined by mountains on either side. But, as recently as the 1990s, people
kept telling me, it had been a wildlife paradise. One man remembered sitting in
the mountains at sunset, watching the elephants cross the valley through the
miombo forest, while the lions roared.
On one road
there was a teak plantation on one side and a miombo forest on the other. The
plantation was quiet, symmetrical, empty: there was no undergrowth because teak
leaves kill whatever they fall on. The miombo forest was more familiar to
anyone who loves to be out in the woods: the smell of earth, rotting leaves,
the hum of bees, dove calls, an abundance of complexity and energy.
The valley
is now a patchwork of teak plantations, rice and sugar fields and huge herds of
cattle, so the lions and elephants have all but vanished. The most telling
remains we saw were the burned stumps, like stripped bones, of the forest.
The same
thing is happening everywhere. On the one hand, huge amounts of energy are
going into reforesting the world. The amount of tree cover is actually rising.
The 2011 Bonn challenge aims to bring 350m hectares (864.5m acres) of degraded
land into restoration by 2030, and countries have already signed up 170m
hectares. A impressive number of sometimes surprising countries have increased
their forest cover by more than 20% over the last 25 years: China, Belarus,
Chile, France, Greece, India, Iran, Morocco, the Philippines, Spain, Thailand
and Turkey. It can really, at moments, seem like some kind of success story.
But the
ancient forests, the original, complex, messy forests, continue to disappear,
and some of the most enthusiastic signatories to the Bonn challenge have seen
some of the worst losses. Argentina, for example, has committed to planting 1m
hectares, but meanwhile the ancient Gran Chaco in the north continues to
vanish, replaced by huge fields of soy to feed the farm animals of the world.
Cameroon,
which holds part of the precious Congo basin rainforest, is offering to create
12m hectares of tree cover by 2030, but since 1990 more than 20% of Cameroon’s
forests have been cut down to make way for subsistence farmers and now,
increasingly, for banana and palm oil plantations, to create products that end
up in our supermarket shopping baskets. Nigeria may feel better about itself
after pledging to plant a million hectares, but the fact is that over the last
25 years it has lost more than 10 times that amount, more than half its forests.
For a number of years it even had the highest deforestation rate in the world,
but it was overtaken this year by Ghana, where cocoa bean crops for our
chocolate are replacing the rainforests.
And let’s
not dwell too long on the countries where the rate of loss is just as high and
dramatic but are not even bothering to sign up to Bonn such as Bolivia (80,000
square kilometres gone between 1990 and 2015), North Korea (33,000), Paraguay
(58,000) and Indonesia (a breathtaking 275,000km – an area larger
than New Zealand).
Even the
apparently cheering news that global tree cover is growing is less than it
seems, explains Tim Rayden of the Oxford Forestry Institute. “There is a big
difference between tree cover and forests.” A large number of countries, for
example, are planning to fill their commitments with commercial plantations –
but plantations, which are harvested every 10 years or more regularly, are very
much less effective than tropical forests at capturing carbon. He points to
recent research where scientists worked out the carbon capture potential of
three different reforestation scenarios under the terms of the Bonn challenge.
If the 350m hectares of reforestation are all natural forest, they can capture
as much as 42 petagrams of carbon. The Intergovernmental Panel on Climate
Change believes that to keep global warming below 1.5C 199 petagrams must be
removed from the atmosphere this century, so that is a significant contribution
from the world’s forests.
‘Argentina,
for example, has committed to planting 1m hectares, but meanwhile the ancient
Gran Chaco in the north continues to vanish.’ Photograph: Courtesy of Mighty
Earth
However, if
the trajectory of the plans already submitted carries on, at least 45% of that
cover will be commercial plantation. If our natural forests are protected under
that scenario, the storage potential will be 16 petagrams. But if we continue
to chop into them in the same way that we do at present, the storage potential
will dwindle to just three petagrams.
We wipe out
whatever is complex and other and difficult to manage, and replace it with
nice, easy farms and plantations full of monocultures of pigs and corn and
wheat and palm oil. We like things nice and simple and symmetrical and easy to
control, that’s the problem.
One
possible attempt to staunch some of the flow that is being seriously considered
in the EU is a due diligence law. France already has a law that places a civil
liability on large companies that fail to monitor their supply chains for human
rights and environment issues, and support for Europe-wide regulation –
although not necessarily in that form – is coming from the oddest quarters such
as Nestlé and Mondelez.
There are
other green shoots of optimism too. Consumers are increasingly aware of the
problem, according to Chris West of the Stockholm Environment Institute at the
University of York. Politicians know that something has to change. Brazil, for example,
came in for serious criticism over the Amazon fires during the Madrid climate
change talks. In many ways, say campaigners, the terrible Amazon fires last
summer have helped to focus the world’s attention on these incredibly precious
living organisms that we take so very much for granted.
But, as
usual with this environment lark, there is a dangerous time lag between
becoming aware of the problem and stopping it from happening. Trees may quite
literally grow on trees (all right, just beneath them). But they grow slowly –
and fall before the axes so quickly.
• Bibi van der Zee is a Guardian journalist
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