Does polypropylene affect soil enzyme activity in a landscape tree box?

The use of polypropylene in urban landscaping, particularly in tree boxes, has raised concerns about its potential impact on soil health. Recent studies suggest that polypropylene, a common plastic polymer, may alter soil enzyme activity—a critical indicator of soil microbial function and nutrient cycling.

Soil enzymes, such as dehydrogenase, urease, and phosphatase, play vital roles in organic matter decomposition and nutrient availability. Research indicates that polypropylene fragments can physically disrupt soil structure, reducing microbial habitats and enzyme production. Additionally, chemical leaching from degrading polypropylene may inhibit enzyme function, further compromising soil health.

However, the extent of this impact varies depending on factors like polypropylene concentration, soil type, and environmental conditions. Some studies show minimal short-term effects, while others highlight long-term risks to urban ecosystems. Sustainable alternatives, such as biodegradable materials or improved waste management, could mitigate these concerns.

Understanding the relationship between polypropylene and soil enzyme activity is essential for designing eco-friendly urban landscapes. Further research is needed to balance practicality and environmental stewardship in modern landscaping practices.