The complex role of the Amazon rainforest

The Amazon rainforest was once called the lungs of the Earth, however, deforestation and over-exploitation mean that scientists are now worried that the rainforest has become a carbon source instead. 

Years of unabated development and deforestation has damaged the Amazon rainforest and destroyed invaluable natural habitat. The impacts of these harmful human activities are far reaching and profound. 

👉 In this article we’ll explore the importance of the Amazon rainforest, the threats it now faces, and what can be done to reverse the damage it’s sustained.

The importance of the Amazon rainforest cannot be understated. The world’s largest tropical rainforest covers over 2.5 million square miles of land, stretches across 9 different countries, is home to 10% of the world’s known biodiversity, and provides 15 to 16% of the world’s total river discharge into the ocean. 

The Amazon is an area of outstanding natural value, and an important tool in the fight against climate change. Let’s take a closer look at some of the functions it plays, and the value that it brings.

Carbon sink

The Amazon rainforest has often been referred to as the lungs of the planet. This is because - generally speaking - the Amazon rainforest draws in carbon dioxide and expels oxygen. Though worryingly scientific studies now suggest that the Amazon is becoming a carbon source - but more on this later. 

The Amazon rainforest has traditionally been thought of as a carbon sink. Carbon sinks are anything that is able to absorb more carbon dioxide than it releases. The world's largest natural carbon sinks include the ocean, its forests, plants, and soil. 

👉 To find out more about the important role carbon sinks play, and why they’re under threat from human activity, why not check out our article on the topic. 

In the past, the Amazon rainforest has functioned as a carbon sink because the trees and vegetation that it contains absorb carbon dioxide from the atmosphere as part of their energy making process, known as photosynthesis. The carbon dioxide is then stored in their roots, branches, and leaves. 

Carbon sinks are essential for tackling climate change and preventing further global warming. By absorbing excess carbon emissions they prevent the levels of atmospheric carbon dioxide from rising even further.

Water cycle

Rainforests such as the Amazon also have an important role to play when it comes to the Earth’s water cycle. 

👉 The water cycle - also known as the hydrologic or hydrological cycle - describes the continuous movement of water within the Earth and its atmosphere. It’s a highly complex system that involves a number of processes, namely: condensation, precipitation, infiltration, runoff, and evapotranspiration. 

The Amazon rainforest contributes to this cycle by adding water to the atmosphere through evapotranspiration. During photosynthesis plants and trees release water vapour which is absorbed into the atmosphere. This moisture in the air helps rain clouds to form, which in turn releases water back into the rainforest through rainfall.

When these forests are cut down, the atmosphere absorbs less water and rainfall declines - sometimes causing drought. 

And the impacts don’t just stop there because rainforests like the Amazon not only affect regional weather patterns, they also impact weather conditions in areas around the world. This is because the moisture absorbed into the atmosphere travels around the world and influences different weather systems. It’s in this way that the Amazon rainforest is able to affect the agricultural output of countries that lie thousands of miles away. 

👉 The Amazon rainforest releases around 20 billion tonnes of water into the atmosphere every single day. It plays a critical role in regional and global water cycles.

Biodiversity

The Amazon is incredibly biodiverse, and is home to at least 10% of the world’s (known) species - that means that one in ten species on Earth can be found within the Amazon rainforest!

And these impressive numbers are continuing to grow as we discover more and more species. Between 1999 and 2009, 1,200 new species of plants and animals were discovered in the Amazon rainforest. 

What’s more is that many species of animals, flora and fauna can only be found in the Amazon. Creatures like the Amazon river dolphin, the giant otter, the bald uakari (a type of primate), the gray woolly monkey, the golden lion tamarin, and the pygmy marmoset - to name just a few.

These creatures all play an important role in the complex ecosystem that is the Amazon rainforest and help to keep the forest healthy. To provide an illustration of this, take the example of a mammal eating the vegetation growing in the forest, this organic material eventually makes its way back to the forest floor in the form of feces, carcasses, and food scraps. The organic material decomposes, releasing nutrients into the forest floor, which benefits the microbes living there, helping them to capture more carbon and preventing it from being released into the atmosphere. It’s a continuous natural cycle!

Medicine and research

Because the Amazon rainforest is home to over 40,000 different plant species it holds enormous potential when it comes to medicine and research. In fact, 25% of all Western drugs are derived from rainforest plants. And since around only 5% of the Amazon’s plants have been studied, there is huge potential for the discovery of new medicines and treatments. 

Examples of some of the incredible purposes that Amazon flora and fauna has been used for include: 

• Quinine - this bark was first discovered by the Quechua tribe, residing in Peru and Bolivia. It now plays an important role in the treatment of malaria. 
• Madagascan Periwinkle - this beautiful pink flower is used in drugs that help to slow down the spread of cancer. 
• ACE inhibitors (Angiotensin Converting Enzyme) - created by a tropical viper found in the Amazon, ACE inhibitors are now used by millions of people around the world to control hypertension. 

And these examples barely scratch the surface when it comes to the medicinal uses provided by the Amazon’s natural resources.

In recent years, the Amazon rainforest has increasingly been hitting the headlines for all the wrong reasons. Wildfires have destroyed swathes of biodiverse forest, killing a myriad of animals and destroying important vegetation. 

Forest has been flattened and cleared to make way for seemingly unabated development. Industrial scale farming, logging, and mining activities are placing increasing pressure on the rainforest system, harming biodiversity, destroying habitat, and threatening local communities. 

In this section we’ll take a closer look at some of the threats that the Amazon is now facing:

Development in the Amazon is a huge threat and a driving force of harmful activities there. Many countries and governments actively promote development within the Amazon rainforest, allowing for clearance of forest to make way for cattle ranches, soybean production, or mining or drilling operations.

It’s also important to note that much of the development is in response to growing international demand for raw goods. Beef is being consumed around the world, and soy is now an important ingredient in a huge number of food products. 

And not only this, our increasing reliance on technology and the drive to create more environmentally friendly electric vehicles is also (ironically) resulting in the destruction of the Amazon rainforest. Forest is being cleared to make way for mining projects that will provide the very ingredients found within lithium batteries - ingredients such as lithium, nickel and copper.

Development is driving deforestation within the Amazon rainforest. In Brazil for example, forest is most often destroyed to make way for cattle ranches. 

The problem is especially prevalent in regions close to settlements and urban areas. However, even remote sections of the Amazon rainforest are no longer safe - with land being cleared to make way for increased mining activity. 

Deforestation is probably the single biggest threat to the Amazon rainforest. The effects are extensive and highly damaging. Let’s take a closer look at some of these below:

Loss of biodiversity

When forest and vegetation is cleared to make way for development, not only are we actively destroying important plants, we’re also destroying habitat. A huge number of important and unique species call the Amazon their home, and by destroying their habitat we can expect to see significant loss of biodiversity in the Amazon.

Where species are only found within a certain geographical area, it’s possible that the destruction of their habitat results in their extinction.

Degradation of ecosystems

The development of cattle ranches, mining facilities, and the creation of infrastructure such as roads and highways to support these activities are creating an increasingly fragmented rainforest. 

This has a significant impact on fragile ecosystems. Ecosystems interact with each other in complex ways that are often difficult to understand or predict, and by fragmenting these areas of biodiversity, we can irreversibly disrupt their natural balance, causing their degradation and harming the different species that reside within them.

Disruption to the water cycle

Deforestation interrupts the water cycle. When we clear trees and plants we are actively reducing the amount of water that is able to be absorbed into the atmosphere. This can have a severe impact on the amount of rainfall within the Amazon, thereby increasing the risk of drought and forest fires and contributing to global warming through the release of carbon dioxide.

However, the impacts extend beyond the immediate region, because the Amazon’s water cycle also influences weather systems elsewhere in the world. The regions that will be most impacted can be found in the south of South America, where a lot of agricultural land is concentrated. Decreased rainfall in this region may have a serious knock on effect in terms of agricultural output and food supply.

Decreased ability to absorb carbon dioxide

We’ve already talked about how the Amazon rainforest has functioned as a carbon sink in the past. Its trees, vegetation and soil absorb carbon dioxide from the atmosphere, helping to limit the damaging effects of climate change. 

By cutting down these trees and clearing vegetation, we are reducing the Amazon’s ability to absorb carbon dioxide and limiting its function as a carbon sink. 

Forest fires

In 2022, forest fires burning in the Amazon rainforest hit a 15 year record high, with thick smoke reaching all the way down to Sao Paulo, 2,500 kilometers away. The reason for this? Deforestation. 

Forest fires in the Amazon rainforest tend to be man made. Farmers cut down the trees and set fire to areas of vegetation in order to make way for agricultural land. 

Usually the forest fires wouldn’t be able to grow too big - this is because the rainforest is naturally very humid, making it difficult for forest fires to ignite and spread naturally. However, deforestation is making the Amazon rainforest drier, and coupled with higher temperatures due to global warming, these conditions are increasing the risk of forest fires burning out of control.

In 2021, it was reported for the first time that the Amazon rainforest was emitting more carbon dioxide than it was able to absorb. 

The primary reason for this is deforestation and uncontrolled forest fires. Forest fires in the Amazon rainforest reached new heights during the rule of Brazil’s previous president - Jair Bolsonaro. Under Bolsonaro’s rule increasingly large areas of the Amazon rainforest were allowed to be cleared to make way for agricultural land and other development projects. 

However, even without these devastating forest fires, deforestation is increasing incidences of drought and heat waves, which is reducing the Amazon’s ability to absorb carbon dioxide from the atmosphere. Even more worryingly, scientists have discovered that part of the Amazon rainforest (the south-east region) was emitting carbon even without the presence of forest fires.

Another study came to the same conclusion, having found that the Brazilian Amazon rainforest had released around 20% more carbon dioxide into the atmosphere over the last ten years than it had absorbed.

The good news is that it is actually possible to reverse some of the damage to the Amazon rainforest and to ensure that it absorbs more carbon dioxide than it produces. The bad news is that it’s not an easy or quick fix. 

The first and most important way to reverse the damage is to drastically limit deforestation and to prevent the uncontrolled forest fires. But achieving this requires political support from governments in control of the different regions of the Amazon rainforest. 

In Brazil in particular, farmers guilty of starting forest fires, have gone unpunished. Politicians have turned a blind eye to the practice and policies have been introduced that make it even easier to clear the Amazon rainforest to make way for development. Thankfully, President Bolsonaro’s rule is now over, and Brazil’s new President - Luis Inácio Lula da Silva - has vowed to take steps to protect the Amazon and end deforestation. 

If this is to be achieved, and the Amazon returned to its role as a carbon sink, deforestation must end, penalties for starting illegal forest fires must be enforced, reforestation efforts must be increased, and indigenous communities must be supported. Achieving these aims will require huge investment from governments as well as international funding - but the cost of failing to do so is even higher.

Indigenous communities have been calling the Amazon rainforest home for thousands of years, accumulating knowledge and helping to protect and preserve these important forests. 

However, over the years, due to the arrival of colonists and a growing number of settlers, their communities and ways of life have increasingly come under threat. 

Nowadays most indigenous communities in the Amazon live in reserves, known as resguardos. In Brazil, indigenous communities have been able to directly participate in the demarcation of their land, and so here these areas are known as ‘indigenous lands’. 

Many believe that indigenous communities are the key to the conservation of the Amazon rainforest. They hold the knowledge and wisdom required to both provide for their communities while also protecting the future of the forest. 

Their care and respect for the forest ensures that they are able to live in harmony with nature. Indigenous communities are not the ones who are depleting the Amazon’s resources, quite the opposite, they are often the ones preserving it. 

The Amazon’s future

The future of the Amazon rainforest now hangs in the balance. Once called the lungs of the earth, some studies suggest that the rainforest has actually become a carbon source instead of a carbon sink. 

However, all is not lost, the Amazon rainforest can be saved, provided the political will and funding is put in place to protect this incredible natural resource.

At Greenly we can help you to assess your company’s carbon footprint, and then give you the tools you need to cut down on emissions. Why not request a free demo with one of our experts - no obligation or commitment required. 

If reading this article has inspired you to consider your company’s own carbon footprint, Greenly can help. Learn more about Greenly’s carbon management platform here.