Quantitative study of microplastic degradation in urban hydrosystems: Comparing in situ environmentally aged microplastics vs. artificially aged materials generated via accelerated photo-oxidation.

The degradation of plastic waste is a major research challenge due to the adverse impacts of microplastic weathering on the environment and ecosystems. As a major source of plastic contamination comes from urban hydrosystems, studying MP degradation prior to their environmental dissemination is crucial. Through a combination of field sampling and laboratory experiments, this study provides a thorough statistical degradation comparison analysis between polyethylene in situ environmentally aged microplastics and artificially aged films.

Tracking the effects of dam construction and restoration on side channel biodiversity using macrofossils in river sediment records.

During the last decades, fluvial sediment cores have been used to reconstruct and model pollution trends, especially for the post-1945 period. Ecological changes have been rarely studied in such recent sediment archives due to low organic levels and high hydro-sedimentary dynamics. Here, we address the challenge of reconstructing ecosystem changes along highly anthropized rivers by analysing plant macrofossils (e.

Temporal trajectories of artificial radiocaesium Cs in French rivers over the nuclear era reconstructed from sediment cores.

Cs is a long-lived man-made radionuclide introduced in the environment worldwide at the early beginning of the nuclear Era during atmospheric nuclear testing's followed by the civil use of nuclear energy. Atmospheric fallout deposition of this major artificial radionuclide was reconstructed at the scale of French large river basins since 1945, and trajectories in French nuclearized rivers were established using sediment coring. Our results show that Cs contents in sediments of the studied rivers display a large spatial and temporal variability in response to the various anthropogenic pressures exerted on their catchment.

Contrasting platinum trajectories in three major French rivers using dated sediment cores (1910-2021): From geochemical baseline to emerging source signals.

Platinum (Pt) is a Technology Critical Element (TCE) which, since the 1990s, has been mainly used in the industry in catalytic converters for automobile emission control. Previous studies have shown Pt contamination of road-side sediments and surface sediments in urban rivers and lakes but few of them have addressed temporal variations. The present work presents historical Pt concentration trends in Cs-dated sediment cores from floodplains or secondary channels at the outlets of three major French watersheds (Loire, Rhone, and Seine Rivers) covering the past ∼110 years, i.

Contribution of different land use catchments on the microplastic pollution in detention basin sediments.

The assessment of microplastic (MP) pollution in urban areas is essential considering its abundance in freshwater, particularly due to urban wet weather discharge. The precise sources of MPs must be identified to better understand its characteristics. This study examines the relationship between MP pollution in detention basin sediments and land use in the investigated catchments.