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Higher-order temporary community consequences through triplet evolution.

In order to understand the origin of plastic debris pollutants that accumulate in the Canary Islands coastline, six beaches of Gran Canaria Island were studied during different seasons to estimate the abundance and the types of two microplastics fraction sizes (0.01-1 mm and 1-5 mm) and mesoplastics fraction (5-25 mm). For the larger fraction of microplastics and mesoplastics, a high percentage of fragments and foams were found; moreover, both fractions show the same accumulation pattern in relation with the wave, wind, and current. The debris was checked for exogenous and local origins. Moreover, for the smaller fraction of microplastics, only natural, semi-synthetic, and synthetic fibres were found, showing a totally different spatial distribution from the others fractions. This result suggests a possible endogenous origin of the contamination, in relation to the type and amount of wastewater discharges and beach users. Repeated reports of microplastic pollution in the marine pinniped diet have emerged in the last years. However, only few studies address the drivers of microplastics presence and the potential implications for monitoring microplastic pollution in the ocean. This study monitored their in the scats (N = 205) of four pinniped species/subspecies at five different locations in the southern Pacific Ocean (Peru and Chile). Samples from all rookeries contained microplastics, and overall, 68% of the examined scats contained fragments/fibers, mostly blue colored. We confirmed that 81.5% of the fragments/fibers were anthropogenic in origin , but only 30% were polymers. Scats from Juan Fernández Archipelago presented higher microplastic concentrations than continental rookeries. Also, the common diet in each location may influence the levels found in the samples. This study presents a useful non-invasive technique to track plastic pollution in top predator diets as bioindicators for future surveillance/management plans applied to different location. Vorinostat supplier The distribution and accumulation of floating marine debris in the Black Sea during the last few decades are analysed by the help of numerical modelling. An approach based on a mesoscale circulation model combined with a particle tracking model is applied. Vorinostat supplier It is established that the litter distribution is nearly independent of the source location and is mainly controlled by the basin circulation system. The western gyre predominantly accumulates floating debris in summer. After the integration of the main cyclonic current in winter, the debris in the inner basin moves east. Retention zones along the south-western coast persist in time. The mean particle stranding time is estimated at about 200 days. Accumulation zones along the south-eastern and eastern coast are abundant in summer, and then move further northeast and north. Simulations demonstrate an increasing litter accumulation in summer on the North Western Shelf and shelf break. Microplastics (MPs) pollution has been increasingly investigated in marine and freshwater environments, even in atmosphere in China. Current literatures show that MPs contamination is highly related to human activities and geomorphology. Higher MPs occurrences were detected in freshwaters than those in seawaters in China. Furthermore, the abundance of MPs was influenced by many factors, including sampling method, unit of measurement, characteristics of sampling area, and others. Currently, investigating the condition of MPs occurrences and distribution on a broader scale and developing standardized protocol, along with basic toxicological research, will help to address crucial knowledge gaps regarding MPs pollution, their interaction with other pollutants and ecological consequences on individual, population or ecosystem levels in the environment. Meanwhile, this review calls for more efforts to be made for better and scientifically sound risk management for mitigation of MPs pollution in China. This study provides the first preliminary assessment of the potential impact from the recent oil spill in the Southern Atlantic Ocean. Using information on the occurrence of oil patches along the Brazilian coast, we quantified potential exposure of marine coastal habitats (estuaries, mangroves, beaches, seagrass meadows, tidal flats, and coral reefs) to oil-related disturbances. We also evaluated which threatened species in the coastal zone may have been impacted and the magnitude of the impacts on socioeconomic activities (i.e. artisanal fisheries and local tourism). Estuaries, mangroves, and seagrass meadows had the highest footprint among the habitats assessed. A total of 27 threatened coastal species occur within the area impacted by the oil residue. Approximately 870,000 people, employed in both artisanal fisheries and local tourism, appear to have been affected by the oil spill. We pinpointed priority areas for monitoring of contamination and accumulation in marine biota. This study aims to identify, classify, quantify the ingested microplastic by marine teleost fish, in order to analyze the relationship between microplastic and trophic guilds. Food items of 214 individuals of Opisthonema oglinum, Bagre marinus, Cathorops spixii, Sciades herzbergii, Chloroscombrus chrysurus, Conodon nobilis, Haemulopsis corvinaeformis were analyzed. The species were classified according to their trophic guilds (zoobenthivorous or opportunistic/omnivorous). All species ingested microplastic and contamination occurred independently of the trophic guild. Of the sampled fish, 55% were contaminated by microplastic. The most consumed categories were blue (28%) and transparent filaments (20%). Raman spectroscopy measurements detected that most sampled filament corresponds to blue synthetic fiber (polyester). This study can contribute by filling gaps in knowledge regarding sandy beach impacts, which are environments so highly threatened by human activities around the world and are neglected in terms of use and conservation plans. After spill, the dispersed oil droplets may collide with suspended particulate matter in the water column to form oil-particle aggregates (OPAs) in turbulent environments. It may be an effective pathway to stabilize the oil by taking advantage of the particulate matter to clean up the contaminated waters. A theoretical model in Payne et al. (2003) is adopted to describe the oil-particle aggregation, and a solution method is proposed and validated against a group of experiments. The effect of the particle size and mass concentration on the aggregation has been examined quantitatively in detail. The particles and the oil droplets are consumed at a fixed ratio. Under the same mass concentration, smaller particles can trap more oil droplets, while larger particles tend to interact more quickly with the oil. The oil-particle aggregation rate and the oil trapping efficiency mainly depend on the particle concentration. The theoretical model is applied to predict the decrease of the dispersed oil in nearshore environments, based on the parameters obtained from the experiments.

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