Why killing off biodiversity is the fast-track to hunger
Alex Morrice
It has never felt more important to have an international day to recognise the importance of biodiversity. The 2019 International Day for Biological Diversity follows the publication of the flagship IPBES report, which detailed the full extent of human-driven species extinction and threats. It makes sobering reading. One million species are threatened globally, 75% of terrestrial habitats have been in some way affected by humans, and hundreds of species have been driven to extinction.
Strikingly, land use change, including deforestation, is the biggest threat to terrestrial species, ahead of even climate change. In the tropics, two thirds of land use change are for the production of a handful of globally-traded commodities. Yet global food security depends on the very same rich nature that humans are sweeping away to plant more crops. If we are to move towards sustainable global food systems, we must conserve biodiverse habitats, including our tropical forests.
We need nature
One major benefit of biodiversity is pollination. Pollinators like bees, bats, butterflies and birds are essential for producing food, supporting 87% of the leading food crops worldwide. Without these species, it would cost a significant amount to pollinate crops; one estimate puts the cost of paying people to pollinate fields in the UK alone at £1.8bn a year.
This means the current collapse in insect species and numbers should be of grave concern for anyone working on or concerned about food security. But it’s not just pollinating insects we should be worried about.
The issue of soil has slowly been emerging as an unglamorous but absolutely pivotal aspect of our impact on the natural environment. To grow anything, we need topsoil, yet we lose 30 football pitches of soil a second and it may all be washed away in as little as 60 years. Biodiversity is essential to good soil health.
More biodiverse soils stick together better, reducing erosion, and are better at both breaking down toxic chemicals and producing nutrients for plants to use. This means that if we want to keep food secure, we must protect soil biodiversity.
Every species has a unique role
So it’s clear that we need pollinators and we need organisms in the soil for our farms to function. But what would be wrong with one species of bee to pollinate everything, or to pollinate monocultures of the most important crops we grow? Does it really matter if one species goes extinct as long as a new one which can do the same type of job is available?
Firstly, many species are particularly good at pollinating one specific type of plant, and outperform more ‘generalist’ species in doing so. For example, the red mason bee is 120 times more efficient at pollinating apple blossoms than honeybees. If we lost the red mason bee, it would be much more difficult to pollinate apples, even if another bee species stepped into the gap.
Secondly, more biodiversity means we can better ‘future-proof’ our food systems. Biodiverse ecosystems are more resilient to a range of threats, including climate change, disease and invasive species. There is more in the biological toolbox to offer in response.
Bananas, for instance, have very low variation, and so a fungus damaging some plants is now threatening the entire $30bn industry. The more diversity within the banana family, the more likely a variety with more resistance will be identified.
A way forward
Current large-scale farming is having a devastating impact on biodiversity. The majority of tropical deforestation is driven by agricultural expansion — for cattle, for soy plantations and for palm oil. And for every parcel of forest lost, we lose a chunk of the most biodiverse terrestrial habitat on the planet.
We are largely familiar with the damage we are doing to large, charismatic species like orangutans, but we are also driving other tiny, vital species to extinction or rarity in their thousands. Species that we depend on for our food. In many cases, when we drive a species to extinction we do not even know they exist. This is particularly the case for small-but-important species, like many beetles and other invertebrates.
This means that the only sure-fire way to protect biodiversity from the sixth mass extinction is to re-think how we grow our food and ensure that tropical forests and other vital habitats are protected. This would protect the tiny organisms that we don’t know about, understand or recognise yet.
This is why Global Canopy focuses on helping the transition to deforestation-free supply chains, aiming to protect tropical forests and the species that live within them. If the cycle of agriculture destroying habitats can be ended, biodiversity will thrive, and so will we.
