I have already covered the causes of deforestation in the Amazon in a previous post, so here I shall cover its effects. The main effect of deforestation you hear about is climate change, but there are many others. Below I briefly outline the main effects, but don’t forget they aren’t mutually exclusive. At the bottom of this post you will find links where you can read more around each of the points if you are interested.
1. Climate change.
Rainforests act as sinks for carbon, and with their destruction they can turn into carbon sources as the trees are burnt and plants decompose. 1 A reduced sink for carbon, means an increase in carbon in the atmosphere contributing to climate change and global warming. The Amazon is actually experiencing droughts due to the warming. 2010 was a severe drought year, with much forest dying back and the Amazon becoming a net emitter of carbon dioxide. 2 In the warmer, drier climate trees struggle to take up as much. 3 Rainforests can also take up a miriad of other greenhouse gases. They fully deserve being called the ‘lungs of the Earth’.
2. Soil erosion.
The removal of trees means there are no longer roots to hold the soil in place. The first instance there is rain, which funnily enough is a very common occurrence in a rainforest, it starts to wash the soil away downstream. Consequently as there are few or no plants to absorb the water, there is more surface run-off which increases the chance of flooding.
3. Loss of biodiversity.
With the loss of trees comes the loss of the plants that live below its canopy, and all the animals that depend on it to survive. This is no small number as rainforests are one of the most biodiverse places on Earth with new species constantly being found. By destroying these rainforests we could in fact be destroying as yet unknown cures for illnesses. Projections suggest that 5–18% of endemic (i.e. occur nowhere else) mammal species will be extinct by 2020. 4 This may have a cascade effect where these species underpin the ecosystem, directly causing the extinction of further species. Do we even have the right to deprive a species of the right to survive?
4. Water table disruption.
The removal of trees leads to reduced water retention in the soil, lowering the water table. This leads to dry and less fertile soils, making it hard to grow crops. Therefore the people who have deforested the land to farm, end up with pretty rubbish growing conditions. In fact the more they farm, the less fertile the soil becomes, however that shall be covered in the next post on the Amazon.
5. Loss of culture and land by indigenous people.
Indigenous people often don’t have any official rights to their land, therefore the government has no qualms about selling it, for example, to oil companies. 5 This obviously is a contravention to their human rights, but all the government wants is money. 6 They simply don’t care about the people who lived their first. Without changes the sale of land for oil will be disastrous for the indigenous people. 7 The destruction of the forest takes away their home, they are forced to integrate into a society where they more than likely don’t speak the language, and hence can swiftly lose their traditions. Medicinal plants they use may also be destroyed along with the forest, and there are loads left for us to discover, or at least there are at the moment! 8 In fact the government should be thanking these people, as they are actually the reason why the Amazon is so fertile (again to be explained in my next post).
One of the big reasons I think most of the world is in denial about deforestation, is you have to see it to believe it. To get a sense of scale of the problem, the mouth of the Amazon alone has an island the size of Switzerland in it. 9
I know that this subject can be a somewhat depressing one, so I will leave you with an inspiring TED talk by Willie Smits discussing how we can restore rainforests.
The next post will be on terra preta, the reason why the Amazon soil is so fertile.