Riverbed depth-specific microplastics distribution and potential use as process marker.

Riverbed sediments have been identified as temporary and long-term accumulation sites for microplastic particles (MPs), but the relocation and retention mechanisms in riverbeds still need to be better understood. In this study, we investigated the depth-specific occurrence and distribution (abundance, type, and size) of MPs in river sediments down to a depth of 100 cm, which had not been previously investigated in riverbeds. In four sediment freeze cores taken for the Main River (Germany), MPs (≥ 100 µm) were detected using two complementary analytical approaches (spectroscopy and thermoanalytical) over the entire depth with an average of 21.

Multi-method analysis of microplastic distribution by flood frequency and local topography in Rhine floodplains.

Rivers are important transport pathways for microplastics into the ocean, but they can also be potential sinks due to microplastic deposition in the sediments of the river bed and adjacent floodplains. In particular, floods can (re)mobilise microplastics from sediments and floodplains, (re)deposit and relocate them depending on the floodplain topography. The knowledge about fluvial microplastic input to floodplains, their spatial distribution and their fate in floodplain soils is limited.

Hydro-geomorphic perspectives on microplastic distribution in freshwater river systems: A critical review.

Freshwater river systems are commonly defined as the main transport paths of microplastics (MP) from land into the seas. A shift in research interest from oceans to rivers can be observed, as a large number of i) case studies, ii) review papers and iii) experimental studies in this field have been published recently. Still, studies often lack an in-depth consideration of quantification, as units are mostly based on item numbers.

Pesticide dynamics in three small agricultural creeks in Hesse, Germany.

Background: Due to their high biodiversity, small water bodies play an important role for freshwater ecosystems. Nonetheless, systematic pesticide monitoring in small creeks with a catchment <30 km is rarely conducted.

Methods: In this study, event-driven water samples were taken from May until November 2017 and March until July 2018 after 20 rain events at three sampling sites with catchment areas of <27 km in the Wetterau, a region with intensive agriculture in Southern Hesse, Germany.

Hydrologic-hydraulic assessment of SUDS control capacity using different modeling approaches: a case study in Bogotá, Colombia.

Urban flooding has increased in response to impervious surface intensification, the loss of green areas, and high-intensity rainfall associated with climate change. Sustainable urban drainage systems (SUDS) are an appealing option for stormwater management; however, their hydraulic control capabilities have received little attention. We developed a comparative model-based approach with 24 scenarios to contrast the hydrologic and hydraulic response of a highly discretized (HD) 1D model and a coupled 1D-2D model, considering the impact of rainwater harvesting systems and tree pits.

The Occurrence of Intersex in Different Populations of the Marine Amphipod in North-West Brittany - A Longterm-Study.

In the past two decades, an increasing body of studies has been published on the intersex phenomenon in separate-sexed crustaceans from marine and freshwater ecosystems. Various causes are being considered that could have an influence on the occurrence of intersex. Besides genetic factors, environmental conditions such as photoperiodicity, temperature, salinity and parasitism, but also environmental pollution with endocrine disrupting chemicals (EDCs) are discussed.

Sand-capping - A large-scale approach to restore organic-enriched estuarine sediments.

Decades of eutrophication have deteriorated marine coastal habitats severely and has led to massive decline of eelgrass along European coastlines and impoverishment of benthic fauna. Although nutrient loadings were reduced and water quality increased decades ago, eutrophication in the past had enriched marine sediments in organic matter to an extent that is still affecting ecosystems today. Organic-rich sediments are readily resuspended, keeping shallow estuaries in a turbid state and benthic fauna communities remain low in density and diversity.

Shine a light: Under-ice light and its ecological implications in a changing Arctic Ocean.

The Arctic marine ecosystem is shaped by the seasonality of the solar cycle, spanning from 24-h light at the sea surface in summer to 24-h darkness in winter. The amount of light available for under-ice ecosystems is the result of different physical and biological processes that affect its path through atmosphere, snow, sea ice and water. In this article, we review the present state of knowledge of the abiotic (clouds, sea ice, snow, suspended matter) and biotic (sea ice algae and phytoplankton) controls on the underwater light field.

Colour marking of small fish with a marking stand for Dermojet.

We designed a marking stand for the Dermojet , which substantially improves fish marking via needleless subcutaneous injection of dye. The marking stand allows to increase the nozzle-to-fish distance, adjust this position and to keep the jet injector fixed during operation as well as dye refilling. A laser pointer enables a precise and small-scale aiming.

Two facets of geotextiles in coastal ecosystems: Anti- or profouling effects?

Nonwoven geotextile fabrics have physical, mechanical and hydraulic properties useful in coastal protection as an alternative to natural stone, slag, and concrete. In a 10-month experiment, the colonisation of macrofouling organisms on different substrata based on polypropylene (PP), polyester (PET) or high density polyethylene (HDPE) fibres was investigated in the Lagoon of Venice, Italy - an environment with temperate transitional waters with high biodiversity - and compared with the colonisation on wood as a reference substratum, because of its occurrence in artificial structures at the study location, until a stable stage was reached in the development of the macrofouling community. Geotextile fabrics showed implications for community development.

Sedimentary microplastic concentrations from the Romanian Danube River to the Black Sea.

A multitude of recent studies have detailed microplastic concentrations in aquatic and terrestrial environments, although questions remain over their ultimate fate. At present, few studies have detailed microplastic characteristics and abundance along a freshwater-marine interface, and considerable uncertainties remain over the modelled contribution of terrestrial and riverine microplastic to the world's oceans. In this article, for the first time, we detail sedimentary microplastic concentrations along a River-Sea transect from the lower reaches of a major continental river, the River Danube, through the Danube Delta, the Black Sea coast to the Romanian and Bulgarian inner shelf of the Black Sea.

Passive sampler phases for pesticides: evaluation of AttractSPE™ SDB-RPS and HLB versus Empore™ SDB-RPS.

In this study, three different passive sampling receiving phases were evaluated, with a main focus on the comparability of established styrene-divinylbenzene reversed phase sulfonated (SDB-RPS) sampling phase from Empore™ (E-RPS) and novel AttractSPE™ (A-RPS). Furthermore, AttractSPE™ hydrophilic-lipophilic balance (HLB) disks were tested. To support sampling phase selection for ongoing monitoring needs, it is important to have information on the characteristics of alternative phases.

Tyre and road wear particles - A calculation of generation, transport and release to water and soil with special regard to German roads.

Tyre and road wear is one of the main emission sources of particulate plastics (microplastics). In this study, the emissions of tyre wear particles (TWP) which are annually generated on the German road network were calculated. Emissions are calculated by applying two different data sets of emission factors and the annual mileage for distinct vehicles and road types (urban roads, rural roads, highways).

Quantitative and qualitative evaluation of plastic particles in surface waters of the Western Black Sea.

Microplastic abundances have been studied intensively in the last years in marine and freshwater environments worldwide. Though several articles have been published about the Mediterranean Sea, only few studies about the Black Sea exist. The Black Sea drains into the Mediterranean Sea and may therefore significantly contribute to the Mediterranean marine pollution.

A Relevant Screening of Organic Contaminants Present on Freshwater and Pre-Production Microplastics.

Microplastics (MPs) have recently been discovered as considerable pollutants of all environmental matrices. They can contain a blend of chemicals, some of them added during the manufacture of plastic to improve their quality (additives) and others adsorbed from the surrounding environment. In light of this, a detailed study about the identification and quantification of target organic pollutants and qualitative screening of non-target compounds present on MPs was carried out in different types of samples: environmental MPs, collected from an Italian river, and pre-production MPs, taken from the plastic industry.

When Good Intentions Go Bad-False Positive Microplastic Detection Caused by Disposable Gloves.

Apart from being considered a potential threat to ecosystems and human health, the ubiquity of microplastics presents analytical challenges. There is a high risk of sample contamination during sampling, sample preparation, and analysis. In this study, the potential of sample contamination or misinterpretation due to substances associated with disposable laboratory gloves or reagents used during sample preparation was investigated.

Biological responses to extreme weather events are detectable but difficult to formally attribute to anthropogenic climate change.

As the frequency and intensity of extreme events such as droughts, heatwaves and floods have increased over recent decades, more extreme biological responses are being reported, and there is widespread interest in attributing such responses to anthropogenic climate change. However, the formal detection and attribution of biological responses to climate change is associated with many challenges. We illustrate these challenges with data from the Elbe River floodplain, Germany.

Microplastics and their possible sources: The example of Ofanto river in southeast Italy.

Monitoring studies have quantified microscopic plastic debris, so-called microplastics, in freshwater systems, including banks, surface waters and sediments. However, there is a lack of knowledge of freshwater and terrestrial environments. When microplastics are released in freshwater environments, they will be transported and will not remain stationary.

Quantification of microplastics in environmental samples via pressurized liquid extraction and pyrolysis-gas chromatography.

The quantification of microplastics (MP) in environmental samples is currently a challenging task. To enable low quantification limits, an analytical method has been developed combining pressurized liquid extraction (PLE) and pyrolysis GC-MS. The automated extraction includes a pre-extraction step via methanol followed by a subsequent PLE using tetrahydrofuran.

Laboratory-to-field extrapolation: Increase in carbamazepine toxicity in a higher tier, multiple-stress experiment.

The toxicity and environmental risk of chemicals, such as the antiepileptic drug carbamazepine (CBZ), is commonly assessed using standardized laboratory tests and laboratory-to-field extrapolation. To investigate the toxicity of CBZ to aquatic key organisms in a more complex and environmentally relevant scenario, we conducted a 32-day multiple-stress experiment in artificial indoor streams. We exposed the non-biting midge Chironomus riparius, the blackworm Lumbriculus variegatus, and the New Zealand mud snail Potamopyrgus antipodarum to 80 and 400 μg CBZ/L in six artificial indoor streams.

Phytoplankton gross primary production increases along cascading impoundments in a temperate, low-discharge river: Insights from high frequency water quality monitoring.

Damming alters carbon processing along river continua. Estimating carbon transport along rivers intersected by multiple dams requires an understanding of the effects of cascading impoundments on the riverine metabolism. We analyzed patterns of riverine metabolism and phytoplankton biomass (chlorophyll a; Chla) along a 74.