They are the most diverse ecosystems on Earth, but recent research confirms how the tropical rainforests are even more important than previously thought. There is a clue in the name – for these ecosystems not only have a lot of rain falling upon them, but actually create it, and not only locally but pumping moisture into the atmosphere to fall thousands of miles from where they stand.
The rainforests are also keeping the planet cooler than it would otherwise be, through catching and holding billions of tonnes of carbon, including some of that being released from planes, cars and power stations. By taking carbon out of the atmosphere and holding it tight in plants and soils, the forests are helping the world to tackle climate change.
And as time has gone on we’ve come to appreciate how the incredibly rich mix of animals and plants found in the rainforests is of far more than scientific interest, and important to save for more than its own sake. For not only is the wildlife diversity a source of our food supply (rainforest species have given rise to many of our most valued foods – including chicken, chocolate, maize and potatoes), but also many medicines, as molecules created through natural selection have been harnessed for among other things treatments for heart disease, anti-cancer agents and powerful painkillers.
Adaptations created in the rainforest are also proving valuable in a whole host of engineering and design applications. The wings of rainforest butterflies have inspired more efficient solar panels, hummingbirds the means to create vivid colour without paint and kingfishers the design ideas to make faster and quieter trains. Ant colonies are being studied to reveal ways of optimising transport networks while other rainforest wildlife is inspiring innovations in optics, acoustics, sensors and the development of composite materials.
So it is that the forests are more than simply collections of trees, but rather webs of connections within which the trees are (to our eyes at least) the most obvious components. The rainforests are tapestries woven from threads of sunshine, water, air, nutrients, photosynthesis, colour, sound and genes, all united into the fabric of an inseparable whole. They are connected by mammalian nuts and bolts, the ecological glue of birds and the strings and struts of insect life; the pollen between the flowers make fruits that are moved by animals including elephants, tapirs, pigs and monkeys, seeding the huge trees that lock up the carbon and pump water into the atmosphere.
But despite our increased understanding as to the intricate complexity and incalculable value of the rainforests, we have not as yet managed to stop their destruction. Across Central and South America, Africa and those parts of Asia and the Pacific where rainforests remain, the pressures on them are as intense as ever. As the forests fall, so water security is being effected, climate changing emissions released, and at the same time one of the best means to removing carbon dioxide from the atmosphere wrecked, while the loss of the rainforests is perhaps the biggest single cause for the mass extinction of animals and plants that is now upon us.
The reasons for on-going forest loss are well documented. The cutting of valuable timber trees not only causes damage to the forest but often opens the access for small-scale farmers, who clear the forest completely to make way for their crops. More devastating still has been the large-scale conversion of forests to fields of soya, ranks of oil palms, open expanses of cattle pastures and plantations of pulpwood and rubber trees, all meeting rising global demand for food and resources.
The good news is that none of these pressures need necessarily lead to forest loss. We increasingly have the means to stop and reverse the destruction. Success is very often bound up with the welfare of local people, whether they be small farmers or the original forest inhabitants, meaning that forest conservation is often as much a social venture as much as it is an environmental one.
For example, in South America one successful conservation strategy has relied upon indigenous rainforest tribes gaining legal control of their ancestral forest homelands. Whereas many outsiders regard the rainforest as an economic resource to be liquidated for financial profit, the Indians regard the intact forest as their home and act to protect it.
In Brazil about 200,000 indigenous people are looking after a huge area that comprises about twenty-five per cent of the total remaining rainforests in the world. In Colombia rainforest Indians control an area larger than Great Britain. In the Asia Pacific region the largest areas of remaining forest are on the island of New Guinea, where the indigenous people have retained control of their forested territories.
Another strategy that can make a difference is the empowerment of small-holders. If the tens of millions of farmers working small plots of land at the edge of the forests can be assisted to make a decent living, then it is more likely that conservation of what remains can succeed. Some of the largest chocolate companies are for example funding social programmes geared toward the protection of forests through helping the farmers who supply their key ingredient to get more out of their land.
Farming based on agroforestry methods has particular potential to make a positive difference. Agroforestry mimics the structure of the rainforest with a variety of crops grown beneath a canopy of fruit, nut or timber trees. Bananas, vegetables and root crops can be combined in ways that conserve moisture and nutrients while minimising the risk of disease and pest infestation.
National parks and other protected areas also have an important role to play and in some regions (such as West Africa) contain most of the forest that is left. So long as they can be maintained in the face of rising demand for land from expanding local populations, then they will be vital for the conservation of countless species, as well as helping sustain regional rainfall.
When it comes to commodity crops like soya and palm oil, then there is potential to rehabilitate some of the vast areas of already degraded lands that exist across the tropics, thereby enabling more output without impinging on remaining areas of natural forest. Many of the world’s biggest consumer brands have adopted ‘zero deforestation’ policies, meaning that market demand for crops grown without forest clearance will in years ahead grow.
Conservationists are finding that the best way to maintain the forests is at the level of landscapes. By looking at the whole landscape it is more likely that sustainable farming, conservation and livelihoods can be achieved together, through the cooperation of local and national governments, local people, funding agencies and the companies buying the commodities needed to make consumer products.
All of this requires money of course, but fortunately multi-billion dollar pledges have during recent years been made by richer countries to help the developing rainforest nations with these kinds of integrated conservation approaches, often on the back of international agreements, such as the 2015 Paris Climate Change accord. There are also powerful new technology-based tools including Global Forest Watch, that enable near real time monitoring of the forests, so that anyone can see if pledges to protect the forests are being met.
Conserving and restoring the tropical rainforests could be the bargain of the 21st century, bringing dividends of benefit the whole world. The task at hand is considerable, but achievable, should we demand that action is taken by governments and large companies to conserve these irreplaceable systems, not least through helping the people who live in and around them.
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