0
Article Tier 2 Environmental Sources Sign in to save

Microplastic fluxes in a large and a small Mediterranean river catchments: The Têt and the Rhône, Northwestern Mediterranean Sea

The Science of The Total Environment 2020 127 citations

AI summary Read the abstract

This study quantified microplastic fluxes in two Mediterranean rivers, the large Rhone and the smaller Tet, finding that fluxes vary markedly through time and space and spike during high-flow events. No clear relationship between microplastic concentrations and hydroclimatic variables was found, highlighting the complexity of riverine microplastic transport.

Study Type Environmental

This paper aims at quantifying current riverine fluxes of microplastics (MPs) in two Mediterranean river catchments, a large one and a small one, namely the Rhône and the Têt, which are discharging to the Gulf of Lion in the Northwestern Mediterranean Sea. MP fluxes change markedly through time and space in both river systems. However, no clear relationships between MP concentrations and hydroclimatic conditions have been observed. In the Rhône River a non-linear dilution pattern of MPs in total suspended matter (TSM) during flood conditions could be observed. Although dilution is important, samples during floods exert a strong control on average MP fluxes. Compared to the Rhône River, average MP concentrations in the Têt River were throughout greater and more variable in shape and polymer composition. However, as the study year was exceptionally dry, the average specific MP flux, 76 g km y, is only slightly larger than the non-flooding value of the Rhône River. We further monitored MP concentrations in shoreline sediments at the mouth of the Têt River to test whether these sediments can represent MP transport in the river. Besides fibers, which probably are easily washed out and transported offshore, MP concentrations and compositions are in agreement with MP loads upstream the river. We also examined the potential role of atmospheric deposition as a source of MP to the Têt River. The average atmospheric MP deposition of 6 kg km y exceeds by far the river average specific MP flux. Moreover, all MPs in atmospheric deposits were fibers, which in terms of mass are of minor importance in the bulk river fluxes. Atmospheric MP deposits may either have been overestimated and/or may be removed from surface waters by efficient removal processes (such as waste water treatment plants).

More Papers Like This

Article Tier 2

Microplastics in two contrasted rivers discharging into the Northwestern Mediterranean Sea

AI summary Read the abstract

This study measured microplastic concentrations in two rivers discharging into the northwestern Mediterranean Sea. The research compared microplastic loads between the contrasting river systems to assess riverine inputs to the Mediterranean.

Article Tier 2

Behavior of macro and microplastics in surface waters in response to extreme meteorological events: a case study on a typical Mediterranean watershed.

AI summary Read the abstract

Researchers measured macro- and microplastic concentrations in Mediterranean freshwaters during dry and wet weather periods, finding that rainfall events dramatically increased plastic loads in urban waterways. More urbanized catchments showed higher plastic concentrations during storm events, confirming that urban stormwater runoff is a major driver of microplastic input to rivers. The study highlights the importance of monitoring during and after rain events to capture the full scale of plastic pollution in urban rivers.

Article Tier 2

Microplastic inputs to the Mediterranean Sea during wet and dry seasons: The case of two Lebanese coastal outlets

AI summary Read the abstract

Sampling of two Lebanese rivers found that microplastic concentrations were far higher in the more urbanized and industrialized river, and that plastic particle loads spiked at the start of the wet season before declining as rain continued—suggesting that seasonal stormwater flushes pulse large amounts of microplastics into the Mediterranean Sea. These results underscore how urban land use and seasonal weather patterns together control the flow of plastic pollution from land to sea.

Article Tier 2

Controls on microplastic flux mechanisms in a large river

AI summary Read the abstract

This study examined the mechanisms controlling microplastic flux in a large river, investigating how flow velocity, particle size, and catchment characteristics influence whether plastics are transported, deposited, or remobilized. Researchers found that microplastic transport is highly dynamic and event-driven, with high-flow events dominating annual transport budgets. The findings provide insights into how rivers function as conduits for delivering plastic to the ocean.

Article Tier 2

Dynamics of microplastics in urban rivers under varying hydrological regimes

AI summary Read the abstract

Monitoring of urban rivers showed that microplastic concentrations fluctuate significantly with varying hydrological conditions such as storm events and seasonal flow changes. Understanding these dynamics is essential for accurately characterizing the river microplastic load and its variability over time.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper