Spatial Distribution and Risk Assessment of Microplastics in Surface Sediment: A Case Study in the Gulf of Gemlik, Marmara Sea

Abstract

Microplastics have increasingly been recognized as a global pollutant due to their pervasive distribution and potential adverse impacts on marine ecosystems. Microplastics (MPs) were collected from surface sediments at five sites in the Gulf of Gemlik using density separation. The isolated MPs were subsequently identified and characterized with a stereomicroscope and fluorescence microscope. This study provides the first comprehensive assessment of microplastic pollution in the sediments of the Gulf of Gemlik, focusing on their abundance, spatial distribution, and potential ecological risks. The concentration of the MPs ranged from 2,200 to 6,400 items per kilogram of dry weight across the study sites. Fibers were the dominant shape type (58.4%), while black was the most prevalent color (26%). According to the ecological risk assessment, the sediments were classified as moderately to considerably contaminated with MPs. These findings contribute new insights into the occurrence and characteristics of microplastics in the surface sediments of the Gulf of Gemlik and establish a foundation for future research and management strategies aimed at mitigating microplastic pollution.

Keywords

• ecological risk
• Gulf of Gemlik
• microplastic
• microscope examination
• Nile Red

Supporting Institution

Research Projects Coordination Unit of Istanbul University, Türkiye

Project Number

FBA-2023-40344

Yüzey Sedimentlerinde Mikroplastiklerin Mekansal Dağılımı ve Risk Değerlendirmesi: Marmara Denizi Gemlik Körfezi Örneği / Spatial Distribution and Risk Assessment of Microplastics in Surface Sediment: A Case Study in the Gulf of Gemlik, Marmara Sea

Abstract

Mikroplastikler (MP’ler), yaygın dağılımları ve deniz ekosistemlerine potansiyel zararları nedeniyle giderek artan şekilde küresel bir kirletici olarak tanımlanmaktadır. Bu çalışmada, Gemlik Körfezi’ndeki beş istasyondan alınan yüzey sedimentlerinden mikroplastikler yoğunluk ayırma yöntemiyle ekstrakte edilmiş; ardından stereomikroskop ve floresan mikroskobu kullanılarak karakterize edilmiştir. Çalışma, Gemlik Körfezi sedimentlerindeki mikroplastik kirliliğine ilişkin bolluk, mekânsal dağılım ve potansiyel ekolojik risklere odaklanan ilk kapsamlı değerlendirmeyi sunmaktadır. Araştırma alanında MP miktarı, kuru ağırlık başına 2200 ile 6400 adet/kg arasında değişmektedir. Mikroplastiklerin baskın şekli lif (%58,4) ve baskın rengi siyah (%26) olarak belirlenmiştir. Kontaminasyon faktörü (CF) ve kirlilik yükü indeksi (PLI) esas alındığında, sedimentlerin orta düzeyde ila oldukça kirlenmiş olduğu saptanmıştır. Bu çalışma, Gemlik Körfezi yüzey sedimentlerinde mikroplastik varlığına dair yeni bulgular ortaya koymakta olup, gelecekte yapılacak araştırmalar ve mikroplastik kirliliğinin yönetimi ile azaltılmasına yönelik stratejiler için bir temel oluşturmaktadır.

Keywords

• Ekolojik risk
• Gemlik Körfezi
• mikroplastik
• mikroskop incelemesi
• Nil Red
• ecological risk
• ecological risk
• microplastic
• microplastic
• microscope examination
• microscope examination

Supporting Institution

İstanbul Üniversitesi Bilimsel Araştırma ve Projeler Birimi

Project Number

FBA-2023-40344

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