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Even though Pacific – Indian Ocean exchange [Indonesian Throughflow (ITF)] has been measured for the last three decades, the measurements of microplastic in the region is very limited. This study was the initial investigation of the vertical distribution of microplastic in the deep-sea areas across the ITF Pathway. Niskin water samples were utilized to obtain the samples from a water column in a range of 5 to 2450 m. A total of 924 microplastic particles with an average abundance of 1.062 ± 0.646. n/L were found in the water column. Our findings indicate that water temperature and water density are the most significant factors correlated to the microplastic concentration. This study will be the first report discussing the distribution of microplastics in the deep-sea water column that could be highly significant in determining the fate and transport of microplastic within Indonesian waters that exits into the Indian Ocean.
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Ingestion of Microplastics in the Planktonic Copepod from the Indonesian Throughflow Pathways
Zooplankton are vulnerable to microplastics in the waters due to their indiscriminate feeding habits. Zooplankton consumption of microplastics affects microplastic accumulation and transmission in the marine ecosystem. Therefore, it is essential to know the intake and transmission by different group sizes of zooplankton in natural seawater. This study documented for the first time the levels of microplastics found in three sizes of copepods along the Indonesian Throughflow (ITF) pathways. The ingestion rates were 0.028, 0.023 and 0.016 n/ind for group sizes copepod 1000-2000 µm, 500-1000 µm and 200-500 µm, respectively. There was no significant distinction in the microplastics concentrations of the three groups of copepod classes along the ITF pathway (p>0.005). Fiber microplastics were the most dominant in the body of copepods, constituting 87.22% of ingested microplastics. In terms of the chemical composition of the microplastic, a total of 7 polymers were detected in copepods in the ITF pathway. The three predominant polymer types identified were polyvinyl butyral (PVB), polyvinyl ether maleic anhydride (PVEMA) and polyester (PES) (27%, 27% and 20%, respectively). This study provides the critical parameters of the microplastic in copepods in the ITF pathway and is an essential basis for further ecological risk assessments of microplastics in biota species.
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- Award ID(s):
- 2242151
- PAR ID:
- 10566111
- Editor(s):
- NA
- Date Published:
- Journal Name:
- Sains Malaysiana
- Volume:
- 53
- Issue:
- 8
- ISSN:
- 0126-6039
- Page Range / eLocation ID:
- 1873 to 1887
- Subject(s) / Keyword(s):
- Indonesian throughflow Makassar Strait Microplastics Capepod Zooplankton
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.17576/jsm-2024-5308-12
