We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Transport and deposition behaviors of microplastics in porous media: Co-impacts of N fertilizers and humic acid.
Summary
Researchers investigated how nitrogen fertilizers and humic acid in soil affect the transport and retention of microplastic particles through porous media in laboratory column experiments. They found that both inorganic and organic nitrogen fertilizers, combined with humic substances, influenced how far microplastics migrated through simulated soil, with implications for subsurface plastic contamination.
Due to the interaction of fertilizers with microplastics (MPs) and porous media, fertilization process would influence MPs transport and distributions in soil. The co-impacts of N fertilizers (both inorganic and organic N fertilizers) and humic substance on MPs transport/retention behaviors in porous media were examined in 10mM KCl solutions at pH 6. NH4Cl and CO(NH2)2 were employed as inorganic and organic N fertilizers, respectively, while humic acid (HA) was used as model humic substance. We found that for all three sized MPs (0.2, 1 and 2 μm) without HA, both types of N fertilizers decreased their transport/increased their retention in porous media (both quartz sand and soil). N fertilizers adsorbed onto surfaces of MPs and sand/soil, lowering the electrostatic repulsion between MPs and porous media, thus contributed to the enhanced MPs deposition. MPs with N fertilizers in solutions more tightly attached onto porous media and thus were more difficult to be re-mobilized by low ionic strength solution elution. Via steric repulsion and increasing electrostatic repulsion between MPs and porous media due to adsorption onto their surfaces, HA could increase MPs transport with N fertilizers in solutions.