The key role of surface tension in the transport and quantification of plastic pollution in rivers

Water Research, Journal Year: 2022, Volume and Issue: 226, P. 119078 - 119078

Published: Oct. 28, 2022

Current riverine plastic monitoring best practices mainly consider surface observations, thus neglecting the underlying distribution of plastics in water column. Bias on budgets estimations hinders advances modelling and prediction fate. Here, we experimentally disclose structure transport flows by investigating how thousands samples commonly found fluvial environments travel turbulent river flows. We show for first time that tension plays a key role since its effects can be same magnitude as buoyancy turbulence, therefore holding part dispersed buoyant captive surface. investigate two types transport; surfaced (surface tension-turbulence-buoyancy dominated), contact with free surface, suspended (turbulence-buoyancy dominated). prove this duality modes is major source error estimation budgets, which underestimated 90 % following current, well-established protocols if sampling conducted solely Based our empirical findings, optimize physics-driven strategies fluxes rivers, thereby achieving over ten-fold reduction bias uncertainty pollution estimates.

Language: Английский

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Wind- and rain-driven macroplastic mobilization and transport on land

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Feb. 16, 2024

Abstract Wind and rain are considered main drivers for mobilization transport of macroplastics on land, yet there is a lack empirical data that quantifies this. We present lab experiment results land-based macroplastic transport. placed four types terrains with varying surface roughness slope angles, exposed them to changing wind speeds intensities. In general, we find the probability velocity strongly depend combination terrain characteristics material properties. At Beaufort 3, 100% plastic bags were mobilized, whereas other less than 50% mobilized. found 1.4 (grass) 5 times (paved surface) higher probabilities land assumed by existing models. Macroplastic velocities positively correlated speed, but not intensity. This suggests transported unless runoff develops can bring afloat. were, driven wind, 1.9 and, rain, 4.9 faster paved surfaces grass. study enhances our understanding provides an basis

Language: Английский

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Defining plastic pollution hotspots

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 934, P. 173294 - 173294

Published: May 18, 2024

Plastic pollution in the natural environment poses a growing threat to ecosystems and human health, prompting urgent needs for monitoring, prevention clean-up measures, new policies. To effectively prioritize resource allocation mitigation strategies, it is key identify define plastic hotspots. UNEP's draft global agreement on mandates prioritizing hotspots, suggesting potential need defined term. Yet, delineation of hotspots varies considerably across studies, definition often lacking or inconsistent without clear purpose boundaries In this paper, we applied four common definitions hotspot locations datasets ranging from urban areas scale. Our findings reveal that these encompass between 0.8 % 93.3 total pollution, covering <0.1 50.3 locations. Given wide range results possibility temporal inconsistency emphasize fit-for-purpose criteria unified approach defining Therefore, designed step-wise framework by determining purpose, units, spatial scale, threshold values. Incorporating steps research policymaking yields harmonized facilitating development effective reduction measures.

Language: Английский

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Disentangling Variability in Riverbank Macrolitter Observations

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(8), P. 4932 - 4942

Published: April 1, 2021

Anthropogenic macrolitter (>0.5 cm) in rivers is of increasing concern. It has been found to have an adverse effect on riverine ecosystem health, and the livelihoods communities depending living next these ecosystems. Yet, little known how reaches propagates through A better understanding transport dynamics key developing effective reduction, preventive, cleanup measures. In this study, we analyzed a novel dataset citizen science riverbank observations Dutch Rhine–Meuse delta, spanning two years over 200 unique locations, with litter categorized into 111 item categories according river-OSPAR protocol. With use regression models, much variation can be explained by hydrometeorology, observer bias, location, instead temporal trends seasonality. The results show that observation bias very low, only few exceptions, contrast total variance observations. Additionally, models precipitation, wind speed, river flow are all important explanatory variables abundance variability. However, number items significantly 19% six display R2 above 0.4. This suggests substantial part variability product chance, caused unaccounted (and often fundamentally unknowable) stochastic processes, rather than being driven deterministic processes studied our analyses. implications findings for modeling movement effectively, probabilistic approach strong uncertainty analysis fundamental. turn, point need planned capture short-term

Language: Английский

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Towards Underwater Macroplastic Monitoring Using Echo Sounding

Frontiers in Earth Science, Journal Year: 2021, Volume and Issue: 9

Published: July 20, 2021

Plastics originating from land are mainly transported to the oceans by rivers. The total plastic transport seas remains uncertain because of difficulties in measuring and lack standard observation techniques. A large focus observations is on plastics floating water surface. However, an increasing number suggest that quantities suspension, below Available underwater monitoring methods use nets or fish traps need be deployed surface labor-intensive. In this research, we explore echo sounding as innovative low-cost method quantify identify suspended macroplastics. Experiments under controlled natural conditions using a off-the-shelf device show items can detected identified up 7 m river Eight different debris (metal can, cup, bottles, food wrappers, container) were characterized based their reflection signature. Reflectance diverged significantly organic material non-plastic anthropogenic debris. During multi-day trial field expedition Guadalete river, Spain, found between 0.8 6.3 depth considerable transported. As most removal strategies upper layer (up approximately 1.5 depth), substantial share may neglected. With paper 1) demonstrate promising tool for monitoring, 2) emphasize importance improved understanding existing loads

Language: Английский

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First insight into the macroplastic storage in a mountain river: The role of in-river vegetation cover, wood jams and channel morphology

The Science of The Total Environment, Journal Year: 2022, Volume and Issue: 838, P. 156354 - 156354

Published: May 29, 2022

Macroplastic storage in mountain rivers remains unexplored and it is unknown how river morphology different surface types of areas modulate this process. Therefore, we sampled macroplastic debris stored on the emergent with vegetation cover wood jams a channelized, single-thread reach an unmanaged, multi-thread Dunajec River Polish Carpathians. Total amounts retained these reaches were then estimated basis mean mass deposited unit area each type given reach. Exposed sediments covered herbaceous significantly lower (0.6 0.9 g per 1 m2 average) than wooded islands (respectively 6 113 m2). The exceeded 19, 129 180 times those found islands, exposed sediments. Wooded covering 16.7% 1.5% 43.8% 41.1%, respectively, total amount that reach, whereas practically absent channelized Consequently, 2.4 wider neighbouring 36 greater km length. Our study demonstrated controlled by channel management style resultant morphology, which hydrodynamics longitudinal pattern zones transport retention conveyed flow.

Language: Английский

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Plastic pollution in marine and freshwater environments: abundance, sources, and mitigation

Elsevier eBooks, Journal Year: 2022, Volume and Issue: unknown, P. 241 - 274

Published: Jan. 1, 2022

Language: Английский

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Sample size requirements for riverbank macrolitter characterization

Frontiers in Water, Journal Year: 2023, Volume and Issue: 4

Published: Jan. 19, 2023

Anthropogenic litter is omnipresent in terrestrial and freshwater systems, can have major economic ecological impacts. Monitoring modeling of anthropogenic comes with large uncertainties due to the wide variety characteristics, including size, mass, item type. It unclear as what effect sample set size on reliability representativeness statistics. Reliable statistics are needed (1) improve monitoring strategies, (2) parameterize transport models, (3) convert counts mass for stock flux calculations. In this paper, we quantify requirement riverbank characterization, using a database more than 14,000 macrolitter items (&gt;0.5 cm), sampled 1 year at eight locations along Dutch Rhine, IJssel, Meuse rivers. We use perform Monte Carlo based bootstrap analysis statistics, determine relation between variability mean median values. Based this, present requirements, corresponding selected uncertainty confidence levels. Optima sampling effort information gain suggested (depending acceptable level), which function type heterogeneity. found that heterogeneity characteristics varies different categories, demonstrate minimum required depends category. This implies heterogeneous categories need be reach same level For example, describe category soft fragments (&gt;2.5 cm) 90% confidence, 990 were needed, while only 39 uniform metal bottle caps. Finally, within assess requirements each river system. All data collected study freely available, may form basis an open access global used by scientists, practitioners, policymakers future strategies efforts.

Language: Английский

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Macroplastic deposition and flushing in the Meuse river following the July 2021 European floods

Environmental Research Letters, Journal Year: 2023, Volume and Issue: 18(12), P. 124025 - 124025

Published: Oct. 26, 2023

Abstract Rivers play an important role in the macroplastics transport and retention dynamics environment. Therefore, gaining understanding of these processes is vital order to help determine fate macroplastic During flood events floating known increase. We compared plastic accumulation flushing on sixteen riverbanks along Dutch Meuse river during period that includes July 2021 extreme same as normal discharge conditions between 2018 2021. Here we show following small categories ( < 2.5 cm) were flushed from riverbanks, while larger soft fragments (2.5–50 wet tissues deposited. found for all averaged, rate was higher than which would be expected time year. However, average locations included lower over winter (Oct/Nov–Feb/Mar). Our results litter category composition differed conditions. This indicates deposition remobilization differ annually These observations contribute a better environment terms drivers both its deposition.

Language: Английский

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On the vertical structure of non-buoyant plastics in turbulent transport

Water Research, Journal Year: 2024, Volume and Issue: 254, P. 121306 - 121306

Published: Feb. 13, 2024

Plastic pollution is overflowing in rivers. A limited understanding of the physics plastic transport rivers hinders monitoring and prediction fate, restricting implementation effective mitigation strategies. This study investigates two unexplored aspects dynamics across near-surface, suspended bed load layers: i) complex settling behaviour plastics ii) their influence on river-like flows. Through hundreds tests thousands 3D reconstructed experiments, our findings show that exhibit unique patterns orientations, due to geometric anisotropy, revealing a multimodal distribution velocities. In particle-bed interactions enhanced mixing beyond what established turbulent theories (Rouse profile) could predict low-turbulence conditions, which extends layer classic definition thickness for natural sediments. We propose new vertical structure considers stochastic nature heterogeneous negatively buoyant singularities.

Language: Английский

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