Like deserts and Arctic wastes, tropical rainforests tend to inspire a feeling of awe in those who visit them. However, unlike these other sparse environments, the majestic forests girdling the Equator represent incredible concentrations of biodiversity, containing more than half of the world’s plant and animal species.

Inside a rainforest, the first impression is one of darkness, a result of shade from the dense tree cover. A complex ecosystem extends from the emergent layer, a top storey that is often home to butterflies, bats and monkeys, down to the forest floor with its fast-decaying plant and animal matter.

Other inhabitants include millions of tribal peoples who have been living close to nature in rainforests for millennia and have devised a way of meeting their needs without destroying their home. The long-term future of many of these indigenous tribes remains under threat from a range of development pressures.

For the Western world, the importance of rainforests is becoming increasingly obvious, with about a quarter of all modern pharmaceuticals derived from rainforest ingredients. A less self-interested motivation is the protection of this rich, diverse web for future generations. In the words of John Seed from the Lismore-based Rainforest Information Centre, “The rainforests are worth preserving because they exist.”

Sadly, more than half of the rainforests have already disappeared, representing a great loss to the world. Regrowth forests do not have the same biodiversity as largely undisturbed forest, so conservation of what remains should remain the top priority.

Deforestation and an alternative

Nearly all rainforests are found in the developing world, often in countries characterised by fast-growing populations and widespread poverty. The per-capita carbon footprint is low but is pushed upwards by the CO2 emissions associated with deforestation. Recent decades have seen a shift away from subsistence farming as the primary driver of rainforest loss towards large-scale and often unsustainable industries, including timber and beef.

In the Amazon Basin, the world’s largest expanse of rainforest, one common scenario is for a logging company to create roads through the forest, facilitating the incursion of poor landless squatters who are too preoccupied with survival to worry about environmental damage. As rainforests have poor soils, these subsistence plots are quickly exhausted, prompting “slash and burn” farmers to move on to another patch.