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Microplastics (MPs) are considered pollutants that are ubiquitously distributed in aquatic environments. One of the key hotspot areas to understand fluxes of MPs entering into the oceans are transitional systems, between fresh and marine waters, where river estuaries in particular play an important role. In this study we analyzed MPs occurrence in the Ebro River Delta, Northeastern Iberian Peninsula, one of the largest wetland areas in the NW Mediterranean Basin. Microplastic profile, abundance, distribution, and characteristics were screened across different environmental matrices. MPs were collected in sandy beaches on the northern edge of the delta, in estuarine benthic sediments, and in surface waters of the Ebro River, with a mean abundance of 422 ± 119 MPs·kg−1 DW, 2052 ± 746 MPs·kg−1 DW and 3.5 ± 1.4 MPs·m−3, respectively. Fibers were found to be the largest class (70 ± 22%) of the three different environmental matrices investigated. We estimated that the Ebro surface water represents an input of 2.14 × 109 MPs·yr−1 to the Mediterranean Sea. The main contribution of this study is a new insight on the distribution of MPs across different environmental matrices in river estuaries, where estuarine benthic sediments were identified as a potential important sink for MPs. Unlabelled Image • Occurrence of microplastic pollution in the Ebro Delta, Spain • Microplastic abundances were investigated in three different environmental matrices. • Microplastics, predominantly fibers, were found in all the samples. • Riverbed benthic sediments were identified as sink areas for microplastics. • Salt-wedge estuaries dynamics may facilitate the sinking of microplastics. [ABSTRACT FROM AUTHOR]

Low frequency, high magnitude storm events can dramatically alter coastlines, helping to relocate large volumes of sediments and changing the configuration of landforms. Increases in the number of intense cyclones occurring in the Northern Hemisphere since the 1970s is evident with more northward tracking patterns developing. This brings added potential risk to coastal environments and infrastructure in northwest Europe and therefore understanding how these high-energy storms impact sandy coasts in particular is important for future management. This study highlights the evolution of Storm (formally Hurricane) Ophelia in October 2017 as it passed up and along the western seaboard of Ireland. The largest ever recorded Hurricane to form in the eastern Atlantic, we describe, using a range of environmental measurements and wave modelling, its track and intensity over its duration whilst over Ireland. The impact on a stretch of sandy coast in NW Ireland during Storm Ophelia, when the winds were at their peak, is examined using terrestrial laser scanning surveys pre- and post-storm to describe local changes of intertidal and dune edge dynamics. During maximum wind conditions (>35 knots) waves no >2 m were recorded with an oblique to parallel orientation and coincident with medium to low tide (around 0.8 m). Therefore, we demonstrate that anticipated widespread coastal erosion and damage may not always unfold as predicted. In fact, around 6000 m 3 of net erosion occurred along the 420 m stretch of coastline with maximum differences in beach topographic changes of 0.8 m. The majority of the sediment redistribution occurred within the intertidal and lower beach zone with some limited dune trimming in the southern section (10% of the total erosion). Asynchronous high water (tide levels), localised offshore winds as well as coastline orientation relative to the storm winds and waves plays a significant role in reducing coastal erosional impact. [ABSTRACT FROM AUTHOR]

External oceanographic conditions rather than anthropogenic influence are shown to cause the 3-dimensional distribution of anthropogenic microparticles (MP, 0.5–5 mm) within the body of sandy beaches of a non-tidal sea with strong wind/wave climate and seasonal sea level variations (the Baltic Sea). A patchy structure is confirmed in all three dimensions, with background concentrations of several tens of MP items per kg of dry sample weight versus peaking spots with several hundreds of items per kg dry weight. The background MP concentrations are of the same order of magnitude for the beach surface, beach body, and sands of underwater coastal slopes, highlighting that the contaminated by MPs sand cover of the entire sea coastal zone is one single entity, repeatedly re-distributed between its underwater and beach parts by every next storm. Peaking concentrations are related to stormy events and places with stronger water dynamics, and are associated with locations of coarser sands within the beach body and wracklines at the beach surface. This suggests that marine waters are the source of anthropogenic microparticles for the beach, and not vice versa. The prevalence of wave-driven over wind-driven beaching mechanism for MPs extracted from the beach samples is confirmed by the flotation tests. Size distribution of the extracted MPs is found to be similar to that obtained for plastics floating at the ocean surface. Such a coherency for different oceanic environments speaks in favor of independence of general fragmentation processes on the particular external conditions, shifting the attention to the fragmentation process and material properties of synthetic particles in marine environment. Capsule Stormy winds, surface waves, and sea level variations rather than anthropogenic load define 3-d variability of pollution by synthetic microparticles within the sand body of beaches. [ABSTRACT FROM AUTHOR]

To investigate the occurrence and distribution of microplastics in the southeastern coastal region of the United States, we quantified the amount of microplastics in sand samples from multiple coastal sites and developed a predictive model to understand the drift of plastics via ocean currents. Sand samples from eighteen National Park Service (NPS) beaches in the Southeastern Region were collected and microplastics were isolated from each sample. Microplastic counts were compared among sites and local geography was used to make inferences about sources and modes of distribution. Samples were analyzed to identify the composition of particles using Fourier transform infrared spectroscopy (FTIR). To predict the spatiotemporal distribution and movements of particles via coastal currents, a Regional Ocean Modeling System (ROMS) was applied. Microplastics were detected in each of the sampled sites although abundance among sites was highly variable. Approximately half of the samples were dominated by thread-like and fibrous materials as opposed to beads and particles. Results of FTIR suggested that 24% consisted of polyethylene terephthalate (PET), while about 68% of the fibers tested were composed of man-made cellulosic materials such as rayon. Based on published studies examining sources of microplastics, the shape of the particles found here (mostly fibers) and the presence of PET, we infer the source of microplastics in coastal areas is mainly from urban areas, such as wastewater discharge, rather than breakdown of larger marine debris drifting in the ocean. Local geographic features, e.g., the nearness of sites to large rivers and urbanized areas, explain variance in amount of microplastics among sites. Additionally, the distribution of simulated particles is explained by ocean current patterns; computer simulations were correlated with field observations, reinforcing the idea that ocean currents can be a good predictor of the fate and distribution of microplastics at the sites sampled here. [ABSTRACT FROM AUTHOR]

Abstract: The Kubuqi Desert suffered more severe wind erosion hazard. Every year, a mass of aeolian sand was blown in the Ten Tributaries that are tributaries of the Yellow River. To estimate the quantity of aeolian sediment blown into the Ten Tributaries from the Kubuqi Desert, it is necessary to simulate the saltation processes of the Kubuqi Desert. A saltation submodel of the IWEMS (Integrated Wind-Erosion Modeling System) and its accompanying RS (Remote Sensing) and GIS (Geographic Information System) methods were used to model saltation emissions in the Kubuqi Desert. To calibrate the saltation submodel, frontal area of vegetation, soil moisture, wind velocity and saltation sediment were observed synchronously on several points in 2011 and 2012. In this study, a model namely BEACH (Bridge Event And Continuous Hydrological) was introduced to simulate the daily soil moisture. Using the surface parameters (frontal area of vegetation and soil moisture) along with the observed wind velocities and saltation sediments for the observed points, the saltation model was calibrated and validated. To reduce the simulate error, a subdaily wind velocity program, WINDGEN was introduced in this model to simulate the hourly wind velocity of the Kubuqi Desert. By incorporating simulated hourly wind velocity, and model variables, the saltation emission of the Kubuqi Desert was modeled. The model results show that the total sediment flow rate was 1–30.99tons/m over the last 10years (2001–2010). The saltation emission mainly occurs in the north central part of the Kubuqi Desert in winter and spring. Integrating the wind directions, the quantity of the aeolian sediment that deposits in the Ten Tributaries was estimated. Compared with the observed data by the local government and hydrometric stations, our estimation is reasonable. [Copyright &y& Elsevier]

Abstract: Quantitative polymerase chain reaction (qPCR) measurement of enterococci has been proposed as a rapid technique for assessment of beach water quality, but the response of qPCR results to environmental conditions has not been fully explored. Culture-based E. coli and enterococci have been used in empirical predictive models to characterize their responses to environmental conditions and to increase monitoring frequency and efficiency. This approach has been attempted with qPCR results only in few studies. During the summer of 2006, water samples were collected from two southern Lake Michigan beaches and the nearby river outfall (Burns Ditch) and were analyzed for enterococci by culture-based and non-culture-based (i.e., qPCR) methods, as well as culture-based E. coli. Culturable enterococci densities (log CFU/100ml) for the beaches were significantly correlated with enterococci qPCR cell equivalents (CE) (R =0.650, P <0.0001, N =32). Enterococci CE and CFU densities were highest in Burns Ditch relative to the beach sites; however, only CFUs were significantly higher (P <0.0001). Culturable enterococci densities at Burns Ditch and the beaches were significantly correlated (R =0.565, P <0.0001, N =32). Culturable E. coli and enterococci densities were significantly correlated (R =0.682, P <0.0001, N =32). Regression analyses suggested that enterococci CFU could be predicted by lake turbidity, Burns Ditch discharge, and wind direction (adjusted R 2 =0.608); enterococci CE was best predicted by Burns Ditch discharge and log-transformed lake turbidity×wave height (adjusted R 2 =0.40). In summary, our results show that analytically, the qPCR method compares well to the non-culture-based method for measuring enterococci densities in beach water and that both these approaches can be predicted by hydrometeorological conditions. Selected predictors and model results highlight the differences between the environmental responses of the two method endpoints and the potentially high variance in qPCR results. [Copyright &y& Elsevier]

Marine litter (ML) consists of any item of anthropogenic origin that has been lost, discarded or intentionally disposed of into the environment, being acknowledged as a worldwide environmental and ecological threat. In the last decade, there has been an attempt across different sectors to tackle, reduce and mitigate sources of litter. In this study, meso and macrodebris between 2 and 30 cm was recorded and classified in two established study areas (Porto Pim and Conceição beaches), throughout five monitoring years (2012–2018). The litter abundance, density and weighted average by abundance were evaluated in eight main categories: plastics , cloths/fabrics , glass , metals , rubber , processed lumber , other and large. Field surveys provided evidence that plastic represented 95% of all litter. ML abundance was treated as an "environmental variable" and used to determine its anomalies, temporal trends and forecasts. Results from this time-series addressed possible periodic oscillations and density peaks of litter. Reference values of ML presence were obtained and could potentially be used for developing a diagnostic tool for anthropogenic pollution in the Azores. Unlabelled Image • Total abundance of ML is 116,540 items with a density of 0.6 ± 0.7 items.m−2. • Marine litter is treated as a climatological environmental variable. • Marine litter is cyclical, and forecasts show a positive trend over time. [ABSTRACT FROM AUTHOR]

Thirty people (mostly children) experienced an episode of skin rash days after a sand sifting beach operation at Porto Pim Beach in Faial, Azores during June 2019. An environmental and epidemiologic investigation was conducted to identify the cause of the outbreak of skin rash. The epidemiologic investigation found that some of the patients experiencing symptoms had never entered the beach water. During the pollution period and throughout the epidemiologic investigation, faecal indicator bacteria levels (94 CFU/100 ml for intestinal enterococci and 61 CFU/100 ml for Escherichia coli) in water remained under the limits used for the ninety-five percentile calculation of an Excellent coastal and transitional bathing water defined in the Portuguese Legislation (100 CFU/100 ml for intestinal enterococci and 250 CFU/100 ml for Escherichia coli). Thus sand contact was considered as a likely primary exposure route. Sand microbiological analysis for faecal indicator organisms and electron microscopy strongly suggested faecal contamination. Chemical analysis of the sand also revealed a concomitant substance compatible with sodium-hypochlorite as analysed using gas chromatography and subsequently confirmed by free chlorine analysis. Inspection of the toilet facilities and sewage disposal system revealed a leaking sewage distribution box. Collectively, results suggest that the cause of the outbreak was the leaking underground sewage distribution box that serviced the beach toilet facilities (40 m from beach), where sodium-hypochlorite was used for cleaning and disinfection. This sewage then contaminated the surficial sands to which beach goers were exposed. Chlorine being an irritant substance, was believed to have been the cause of the symptoms given the sudden presentation and dissipation of skin rashes. No gastro-intestinal illness was reported during this episode and during the following 30 days. Like water, beach sand should also be monitored for safety, especially for areas serviced by aged infrastructure. Unlabelled Image • An episode of skin rash was experience by 30 people at a beach. • Analysis of the sand revealed a substance compatible with NaOCl concomitant high levels of faecal indicator organisms. • Sodium-hypochlorite was used for cleaning and disinfection of toilet facilities. • A leakage in the sewage system was found to have been the cause of the outbreak. [ABSTRACT FROM AUTHOR]

In the Netherlands it is common to nourish the coastline with sand from the seabed. Foredunes are replenished with sand from the beach and can be transported further into the dune area. We investigated whether nourishment material alters the phosphorus (P) content of dune soil and the nitrogen (N):P ratio of dune vegetation in two areas: a mega sand nourishment with fixed foredunes (SE) and a traditional sand nourishment with dynamic foredunes (NWC). Four zones were considered: beach (zone 1), frontal foredunes (zone 2), foredunes crest (zone 3) and inner dunes (zone 4). We estimated the characteristics of fine (< 250-μm) and coarse (250–2000 μm) sand. Total P, P speciation and available P of SE and NWC were similar until zone 4. Zone 1–3 consisted mainly of coarse sand, whereas the sand in zone 4 was finer with higher amounts at NWC. Iron (Fe) bound P was comparable for fine and coarse sand in zone 1–3, but high contents were present in zone 4. In zone 1–3, calcium (Ca) bound P was mainly found in the fine fraction, which was abundant in the coarse fraction of zone 4. After a period of 4 years, the effect of dynamic dunes on P fractions and dune plant species was not apparent yet, although inblowing sand mainly consisted of fine sand with high contents of Ca-bound P. This may change over time, especially in dynamic dunes with higher eolian activity of fine sand. Consequently, pH buffering of the soil may increase because of a higher Ca‑carbonate content, which leads to decreased solubility of Ca-bound P and low P availability for the vegetation. Both low P availability and high buffering capacity are known environmental factors that facilitate endangered dune plant species. Unlabelled Image • Dutch coastlines are commonly nourished with sand from the seabed. • It is unclear if P chemistry is altered when beach sand enters the dune system. • Nourishment material was investigated at a site with and without dynamic foredunes. • After 4 years dune plant species were unaffected by sediment composition changes. • Enrichment of beach-related minerals depended on time and dynamic foredunes. [ABSTRACT FROM AUTHOR]

Plastic pollution is a global problem with great local and regional variability. Plastic litter reaches beaches directly and indirectly through different pathways, due to both terrestrial and marine pressures. In this study, we assess and characterize meso and microplastic pollution on four Uruguayan oceanic beaches along a gradient of tourist use within a complex regional coastal marine system. In Punta del Diablo we found a total mean density of 106 items m−2 of different debris (pellets, fragments, and foams) with different polymeric compositions, and diverse persistent bioaccumulative and toxic chemicals (PAHs, PCBs, OCs, heavy metals). However, the trend of plastic debris densities along this gradient was not what was expected. Fabeiro , one of the sites furthest from the urban center, had the highest total mean density of plastics (292 items m−2) suggesting that marine influences (winds, currents, and beach orientation) have a preponderant role in the distribution of micro and mesoplastics. Meanwhile, the density in the urban site (Pueblo) was highest during summer (March, 201 items m−2), 200 times higher than the density observed in winter (July, 1 item m−2). Although this difference could be associated to the peak season (southern summer), the analysis of types of plastics (171 pellets m−2 vs. 8 cigarette butts m−2) suggested a predominance of marine inputs. Seasonal changes in the configuration of the beaches due to natural geomorphological dynamics imply alternating states (Source or Sink of debris) that also affect the final density of plastics in the system. The relative importance of both sources is highly variable throughout the year and understanding them may directly improve beach management and stranded coastal plastic litter cleaning. Unlabelled Image • Trend of plastic debris densities along the use gradient were not as expected. • Marine coastal currents are particularly important in the distribution of MPs. • Beach alternate states (Source/Sink) affect the balance of plastics in the beach system. • Could coastal dynamics be a key element for ecosystem-based adaptation (EbA) strategies for stranded plastic litter? [ABSTRACT FROM AUTHOR]

Anthropogenic Marine Debris (AMD) is one of the major environmental issues of our planet to date, and plastic accounts for 80% of total AMD. Beaches represent one of the main marine compartment where AMD accumulates, but few and scattered regional assessments are available from literature reporting quantitative estimation of AMD distributed on the shorelines. However, accessing information on the AMD accumulation rate on beaches, and the associated spatiotemporal oscillations, would be crucial to refining global estimation on the dispersal mechanisms. In our work, we address this issue by proposing an ad-hoc methodology for monitoring and automatically quantifying AMD, based on the combined use of a commercial Unmanned Aerial Vehicle (UAV) (equipped with an RGB high-resolution camera) and a deep-learning based software (i.e.: PlasticFinder). Remote areas were monitored by UAV and were inspected by operators on the ground to check and to categorise all AMD dispersed on the beach. The high-resolution images obtained from UAV allowed to visually detect a percentage of the objects on the shores higher than 87.8%, thus providing suitable images to populate training and testing datasets, as well as gold standards to evaluate the software performance. PlasticFinder reached a Sensitivity of 67%, with a Positive Predictive Value of 94%, in the automatic detection of AMD, but a limitation was found, due to reduced sunlight conditions, thus restricting to the use of the software in its present version. We, therefore, confirmed the efficiency of commercial UAVs as tools for AMD monitoring and demonstrated - for the first time - the potential of deep learning for the automatic detection and quantification of AMD. Unlabelled Image • Unmanned Aerial Vehicle (UAV) offers a fast and reliable survey methodology. • UAV used for Anthropogenic Marine Debris (AMD) monitoring • Spatial resolution achieved allowed to detect high percentage of AMD on the shores. • Deep-learning based software automatically detects and quantifies AMD. [ABSTRACT FROM AUTHOR]