The latest research has found that microplastic in the soil is damaging populations of the tiny creatures that maintain its fertility.
Worms, ants, springtails, mites and other forms of microarthropods that are so small we can hardly see them, play an essential role in breaking down organic matter, recycling the carbon and nutrients it contains, into a form that the soil’s fungal and bacterial communities can consume. This nutrient cycle is part of nature’s recycling system, an essential feedback loop that puts resources back into use by a process of decomposition. Without it, complex biospheres begin to fail.
Ants and a springtail feeding in the soil.
While we have focused on the effects of microplastics on our oceans and the horrifying spectacle of the Great Pacific Garbage Patches, we have been ignoring the damage that plastics have been doing, almost invisibly, to the soil under our very feet. Humankind has produced an estimated 8.3 billion metric tonnes of plastic waste since 1950, and 79% of it has accumulated in landfills or leaked into the soils of the natural environment.
The Pacific Garbage Patch (CC0). Researchers believe that the patch covers 1.6 million square kilometres.
At the highest levels of plastic contamination, the most common species of soil micro-organisms, including the larvae of micro moths and many flies, decline by as much as 40%. Bacteria and fungi seem to be less affected but modelling has shown that the impact of the decline of its animal species can cascade through the soil’s food webs, changing the ways fungi and bacteria function in the nutrient cycle.
The above-ground fruiting bodies of fungi are the spore producing mechanisms of sometimes enormous underground mycelia, important elements of the carbon and nutrient cycles.
Covid-19 has turned our attention from environmental issues at the very same time as it has been responsible for a new wave of pollutants: the billions of disposable masks and throw-away latex gloves we are using to keep ourselves and our families safe from the virus. Walking through the park, we have seen masks and gloves, made from plastic derived fabrics, dropped on the paths and in the fields. They will be picked up by our litter pickers and carried away by the council’s waste lorries, to landfill, where they will become part of this problem.
Let’s look after our soil’s vital biodiversity. Masks are essential in a pandemic, but reusable cloth masks are as effective as a surgical mask when you are supermarket shopping. Latex gloves are over-kill when you are walking the dog in the park; washing your hands when you get home, with a good old fashioned bar of soap, is the simplest (and cheapest) way to kill the virus.
The easy way out is often the one with the poorest end result in the long term. Our daily lives are eased in hundreds of ways by the single-use plastics that are slowly, over decades, strangling the biosphere that supports us; we need to make a change.