Climate change: Are trees the answer?

 

China’s great green wall (LINK), is a 50 year project in which they hope to plant 88 billion trees. In North Africa, attempts are being made to stop the advancing Sahara and Sahel deserts (LINK), by planting trees in a corridor from Senegal to Djibouti, stretching almost 8000km through eleven countries. Pakistan is planting 10 billion trees by 2023 (LINK), to mitigate the effects of climate change and soil erosion.

 

There are many more worldwide examples – everyone it seems, loves trees. Large companies like Shell and Nestles are planting trees to offset their carbon dioxide emissions.

 

 NASA estimates there are 3 trillion trees on the planet at present and despite the above examples, the net loss of trees globally, continues. Around 50,000 sq km of the world’s forests have been cleared each year for the last decade. We are still removing trees at a faster rate than we are planting them and Australia is up there with the worst of them!

 

A logging coupe at Neerim East

The science has been saying for some time now, that to avoid the worst effects of global warming we need to limit the rise in global temperature to around 1.5⁰C to 2⁰C. To achieve this, we have to radically curb our emissions as well as remove billions of tonnes of carbon dioxide from the atmosphere.

 

A best guess is that trees could remove about one quarter of the CO₂.

 

Many both small and large tree planting projects have failed. Poor choice of locality, lack of follow up and poor public acceptance are fairly common reasons and now experts are telling us that as the planet heats up, plants appear to be absorbing carbon dioxide less efficiently.

 

Studies show that natural forests can capture more than 40 times more carbon dioxide than a mono-plantation of similar size. Given how little that many tree plantations contribute to biodiversity, the advice from scientists now is that we should be concentrating on protecting our natural forest areas more stringently and where sites are suitable, rather than planting trees, natural regeneration be encouraged.

Natural regeneration Roberts Ct Drouin

 

Apart from all of the above, trees alone are never going to be the answer to global warming, we have to cut our emissions.