Tire wear particles (tiny pieces that rub off car tires) are increasingly being seen as a threat to soil health. These particles can be washed off roads into nearby soil, often by rain. Most research so far assumes that these particles enter the soil all at once, but that’s not always how it happens in real life.
In our study, we looked at how the speed of this pollution—either all at once (abrupt) or little by little over time (gradual)—affects soil conditions and the microbes that live there. We split our experiment into two parts: the period when the tire particles were being added and the period after they stopped.
We found that when the particles were added gradually, they reduced the activity of certain soil enzymes that help break down carbon. When added all at once, the particles had a stronger effect on enzymes related to the nitrogen cycle. Interestingly, after the particles stopped being added, the microbial activity went back to normal—but how quickly this happened depended on how the particles were delivered in the first place.
Click HERE to read the full study