An international team of researchers has found that microplastics that penetrate the soil can lead to a decrease in the number of worms and microarthropods that live there. Microarthropods are one of the groups of soil invertebrates that actively participate in the destruction of organic matter. In a paper published in Proceedings of the Royal Society B, scientists talk about their research into the effects of microplastics in soil.
Microplastics are tiny pieces of plastic that have broken off from larger pieces of plastic. Tiny pieces of plastic are a major source of pollution around the world. Over the past couple of years, there has been a lot of research into the effects of microplastics on creatures that inhabit oceans, rivers, streams, and lakes.
The pollutants have been found to alter the reproductive abilities of sea creatures, and sometimes their habits, making them more vulnerable to predators. In this new work, the researchers examined how microplastic contaminants affect the creatures that live in the soil.
Many creatures live in soil – larger ones, such as ground squirrels and turtles, tend to eat smaller creatures that live in soil or plant material. The soil is also home to a large number of much smaller creatures, including insects, worms, and bacteria. Together they make up the web of life with their own food chain. To learn more about what happens when microplastics enter this environment, the researchers collected microplastics samples and mixed them with fresh, clean soil taken from the ground, along with a variety of endemic organisms. Endemics are a specific component of any flora or fauna. Endemic species include species, genera, families or other taxa of animals and plants, whose representatives live in a relatively limited range, represented by a small geographical area.
After the introduction of microplastics, researchers found that populations of worms and microarthropods (invertebrates that have exoskeletons that can be seen with the naked eye, such as collembolans and ticks) have decreased. Further research showed that as more microplastics were introduced, the number of such creatures decreased. The scientists also noted that the introduction of microplastics into the soil samples did not reduce the number of bacteria living in the soil. Ultimately, scientists hypothesized that microplastics penetrate soil and food webs, making changes that could damage the soil’s carbon and nutrient cycle.