VSCut an apple in half, and the white flesh reveals a cluster of black seeds arranged in the shape of a star. It’s a tiny constellation of seeds hidden in the fruit bowl. But it reveals an intertwined universe of pollination and nature’s abundance – a delicate system and one that can easily be subverted.
When apple blossoms are pollinated, the seeds pumping hormones telling the plant to produce the proper vitamins, minerals and growth rate. They help formulate crunch, size and shape. However, if we lose these pollinators, this fragile system becomes unbalanced. If only three or four seeds are pollinated, our apple may become crooked. The nutritional value could decrease, as could the shelf life of the fruit, with it becoming brown and wrinkled before its time.
The story of the apple is told again and again across the world. A new report warns that two million species are in danger of extinction, twice as many as previous UN estimates. This increase is due to better data on insect populations, which have been less well understood than other groups.
Often, it is animals like insects – the species we tend to worry about the least – that provide the greatest services to human populations: pollinating crops, helping to provide healthy soils and controlling pests.
Despite continued uncertainties regarding invertebrates, the alarming loss of wildlife globally is well documented. Over the past 50 years, wildlife populations have declined by an average of 70% – and their loss is already affecting the functioning and livelihood of human societies.
What happens to pollination?
The latest study estimates that 24% of invertebrates are threatened with extinction – they pollinate the most.
Crops that provide most of our vitamins and minerals, like fruits, vegetables, and nuts, depend on pollinators and soil organisms that keep it fertile. Approximately 75% of food crops depend on pollinators to some extent and 95% of the food comes directly or indirectly from the ground.
Professor Simon Potts, from the University of Reading, says: “If you get less pollination, you will get less production. But not only will the yield or tonnage decrease, but the quality of that product will decrease… your strawberries will be deformed and they won’t be as full of sugars.
“We call this a ‘pollination deficit,’” he says.
A review of scientific databases from 48 countries, published in Nature Communications, covering 48 different crops, found that fruits pollinated by animals and insects were on average 23% better quality than those which have not been pollinated by animals, notably improving the shape, size and shelf life of fruits and vegetables.
Growing short-lived and odd-looking fruits is likely to increase food waste, with an impact felt throughout the production chain, researchers warn.
What does this do to our global food system?
Insect pollination contributes more than £600 million a year for the UK economy. “Biodiversity must be considered a legitimate agricultural input,” says Potts. “Farmers manage water, fertilizers and pesticides, the seeds we plant, but very few of them manage biodiversity as an input. »
Globally, between 3 and 5% of vegetable, fruit and nut production is lost due to inadequate pollination, According to research led by Harvard University and published in the journal Environmental Health Perspectives.
Lead researcher Matthew Smith, who specializes in environmental health, said: “At first glance I was surprised that the figure seemed somewhat modest. »
However, the implications of this 3 to 5 percent loss were significant: It led to about 420,000 additional deaths per year due to a reduction in healthy food consumption and related illnesses, the researchers found.
Smith says, “To put that number in perspective, that’s equivalent to the number of people who die each year from substance use disorders, interpersonal violence, or prostate cancer. »
The economic implications of these losses can also be considerable. A a study showed that a pollination deficit for the UK’s Gala apple crop could equate to £5.7 million in lost production.
Smith’s team modeled a similar loss in economic value of agricultural production in three countries: Honduras, Nigeria and Nepal. They found that between 16% and 31% of their agricultural economic value was lost due to inadequate pollination.
“As between one and two thirds of the population in these countries are employed in agriculture, this is a huge and widespread effect,” he says.
And the water?
Pollinators help provide clean water and sanitation because healthy plant ecosystems keep waterways clean. Mangroves, which benefit from animal pollination, filter pollutants, absorb runoff and promote sedimentation, which helps improve water quality. Since the late 1990s, global mangrove cover has declined about 35%.
A document published in the journal Nature shows that habitats with more species are able to remove pollutants more quickly, improving water quality. Research suggests that wildlife in freshwater ecosystems is disappearing at twice the rate of wildlife in oceans and forests. Only 40% of water in Europe are classified as being in good ecological health.
What is happening to our soil?
When drought hits, we tend to think about the impact on the surface: plants wilt, lakes dry up, people or animals are forced to migrate. But beneath the surface, a parallel crisis is underway.
Climate change has direct negative effects on crops, such as heat stress, but its indirect effects disrupt insect populations and reduce soil biodiversity, where more than half of all species live. A article published in Nature Communications showed that microbes present in soils are not as resilient as previously thought during droughts, which appears to alter their biology.
Professor Franciska de Vries, from the University of Amsterdam, who was the lead researcher on the study, said the immediate impacts of extreme events such as droughts, heatwaves and storms are felt on plants. However, recurring extreme climatic phenomena harm soil biodiversity and the ability of plants to grow in the long term. If it’s really dry for long enough, soil organisms die.
“It’s kind of a double whammy,” says De Vries. “On the one hand, we don’t manage our soils very well, which reduces their ability to cope with these extreme events. At the same time, these extreme events make our soils and crops even more vulnerable. »
According to UN data, up to 40% of land is now classified as degraded, and half of the world’s population is already suffering the impact of depleting soil fertility, water, biodiversity, trees or native vegetation. Under these conditions, diseases are more likely to take hold, because the system is weakened and certain soil organisms have been annihilated.
“If you have healthy soils with organisms that can help plants, you mitigate the effects of these extreme events to some extent.”
When will these effects start to be felt?
How humans will be affected by the loss of nature is often presented as something that will happen in the future. Despite all the effects of the disappearance of nature – which are already being felt – awareness of the biodiversity crisis still lags behind that of the climate crisis.
“I think biodiversity is what climate was 20 years ago,” Potts says. “I think until the public really wakes up to the reality that ‘his life has changed’, I don’t think research alone will convince people – look at the climate story. “