Wind- and rain-driven macroplastic mobilization and transport on land

Area of Science:

• Environmental Science
• Earth Science
• Polymer Science

Background:

• Macroplastic pollution on land is a significant environmental concern.
• Wind and rain are hypothesized as primary drivers for macroplastic mobilization and transport.
• Empirical data quantifying land-based macroplastic movement remains scarce.

Purpose of the Study:

• To experimentally quantify the mobilization and transport of macroplastics on land under varying environmental conditions.
• To compare empirical findings with existing macroplastic transport models.
• To investigate the influence of terrain characteristics and material properties on macroplastic movement.

Main Methods:

• Laboratory experiments simulating wind and rain exposure on different macroplastic types.
• Utilizing terrains with varying surface roughness and slope angles.
• Measuring mobilization probability and transport velocity under controlled wind speeds and rain intensities.

Main Results:

• Macroplastic mobilization and transport are strongly dependent on the interplay between terrain characteristics and material properties.
• Mobilization probabilities on land were found to be 1.4 to 5 times higher than predicted by existing models.
• Macroplastic transport velocity correlated positively with wind speed but not rain intensity, unless surface runoff occurred.

Conclusions:

• Wind is a more significant driver of macroplastic transport on land than rain, except in cases of surface runoff.
• Paved surfaces facilitate significantly faster macroplastic transport velocities compared to grassy terrains.
• The study provides crucial empirical data to improve land-based macroplastic transport models and inform mitigation strategies.