Abundance and distribution of marine litter on the beaches of Okinawa Island, Japan

Ifenna Ilechukwu; Rocktim Ramen Das; Emmeline A Jamodiong; Stefano Borghi; Geminne G Manzano; Agus Alim Hakim; James Davis Reimer

doi:10.1016/j.marpolbul.2024.116036

Abundance and distribution of marine litter on the beaches of Okinawa Island, Japan

Mar Pollut Bull. 2024 Mar:200:116036. doi: 10.1016/j.marpolbul.2024.116036. Epub 2024 Jan 18.

Authors

Ifenna Ilechukwu¹, Rocktim Ramen Das², Emmeline A Jamodiong², Stefano Borghi³, Geminne G Manzano², Agus Alim Hakim⁴, James Davis Reimer⁵

Affiliations

¹ Molecular Invertebrate Systematics and Ecology (MISE) Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa 903-0123, Japan. Electronic address: iilechukwu@madonnauniversity.edu.ng.
² Molecular Invertebrate Systematics and Ecology (MISE) Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa 903-0123, Japan.
³ College of Science and Engineering, James Cook University, Townsville, QLD, Australia; Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa 903-0123, Japan.
⁴ Molecular Invertebrate Systematics and Ecology (MISE) Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa 903-0123, Japan; Department of Aquatic Resources Management, Faculty of Fisheries and Marine Sciences, IPB University, JI. Agatis, Kampus IPB Dramaga Bogor, 16680, West Java, Indonesia.
⁵ Molecular Invertebrate Systematics and Ecology (MISE) Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa 903-0123, Japan; Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa 903-0123, Japan.

PMID: 38237260
DOI: 10.1016/j.marpolbul.2024.116036

Abstract

This study evaluated the distribution and abundance of marine litter on 30 beaches around Okinawa Island, Japan. Beach quality indices and multivariate statistical analyses were used to assess the quality of the beaches and their pollution patterns. A total of 11,626 items weighing 513.49 kg with an average density of 0.13 ± 0.10 items/m² were collected. Litter was dominated by plastics (81.72 %), broken glass (8.38 %), and cigarette butts (7.44 %), and 74.05 % of total litter was from land-based sources. Single-use plastics (SUPs) were present in all surveyed beaches and made up 30.54 % of the total litter. The clean coast index (CCI), plastic abundance index (PAI), and hazardous index (HI) were between 0.1 and 7.6, 0.1-4.0 and 0.01-1.42, respectively, indicating low to moderate levels of pollution of Okinawan beaches. This study should aid in the formation of strategies to deal with marine litter in Okinawa, other areas of Japan and the Asia-Pacific region.

Keywords: Cigarette butts; Clean coast index (CCI); Marine debris; Plastic bottle caps; Pollution; Single-use plastics.

MeSH terms

Bathing Beaches
Environmental Monitoring*
Japan
Plastics / analysis
Waste Products* / analysis

Substances

Waste Products
Plastics