Documenting the emergence of a new mucilage formation in the Sea of Marmara in 2024

Abstract

Mucilage represents a significant environmental disaster in marine ecosystems, with the potential to leave permanent effects on biodiversity. In this study, we document the first mucilage formation of the year detected in the Gulf of Erdek, south of the Sea of Marmara (SoM), on October 23, 2024. Our findings align closely with historical data, reinforcing the trend of increasing mucilage events in the region. Field studies revealed sea surface temperatures reaching 21.2 °C, well above seasonal norms, indicating thermal anomaly. Due to insufficient water flow and vertical mixing, the thermocline layer could not be observed until it reached 28.4 m, resulting in consistent temperatures ranging from 19.6 °C to 21.2 °C. Furthermore, primary production remains alarmingly high, with nutrient inputs in the SoM exceeding natural capacities, as evidenced by chlorophyll levels of 2.4 mg/m³. Anthropogenic factors, including domestic, industrial, and agricultural wastes, create a persistent substrate for mucilage formation, exacerbated by temperature anomalies and stagnant water conditions. If these trends continue, mucilage could continue to be a persistent environmental hazard in the SoM. Thus, while treatment remains the most viable solution for waste reduction, urgent and comprehensive measures are essential to mitigate this growing threat to the marine ecosystem.

Keywords

• Marine mucilage
• Eutrophication
• Nutrient enrichment
• Chlorophyll levels
• Temperature anomalies
• Mediterranean basin

2024 yılında Marmara Denizi'nde yeni bir müsilaj oluşumu

Abstract

Müsilaj, deniz ekosistemlerinde biyolojik çeşitlilik üzerinde kalıcı etkiler bırakma potansiyeline sahip önemli bir çevre felaketini temsil eder. Bu çalışmada, 23 Ekim 2024'te Marmara Denizi'nin güneyindeki Erdek Körfezi'nde tespit edilen yılın ilk müsilaj oluşumunu belgeledik. Bulgularımız tarihsel verilerle yakından örtüşmekte ve bölgedeki müsilaj olaylarının artış eğilimini desteklemektedir. Saha çalışmaları, deniz yüzeyi sıcaklıklarının mevsim normallerinin oldukça üzerinde, 21.2 °C'ye ulaştığını ve bunun sıcaklıkla ilgili anomaliye işaret ettiğini ortaya koymuştur. Yetersiz su akışı ve dikey karışım nedeniyle 28.4 m'ye kadar termoklin tabakası gözlemlenmemiştir ve bunun sonucunda 19.6 °C ile 21.2 °C arasında değişen tutarlı sıcaklıklar oluşmuştur. Dahası, birincil üretim endişe verici derecede yüksek seyrederken besin girdileri, 2.4 mg/m³ klorofil seviyeleriyle kanıtlandığı gibi doğal kapasiteleri aşmaktadır. Evsel, endüstriyel ve tarımsal atıklar da dahil olmak üzere antropojenik faktörler, sıcaklık anormallikleri ve durgun su koşulları nedeniyle daha da kötüleşen müsilaj oluşumu için kalıcı bir zemin oluşturur. Bu eğilimlerin devam etmesi halinde müsilaj Marmara Denizi'nde kalıcı bir çevre felaketi olarak görülmeye devam edebilir. Dolayısıyla, atık azaltımı için arıtma en geçerli çözüm olmaya devam ederken, deniz ekosistemine yönelik bu artan tehdidi azaltmak için acil ve kapsamlı önlemler şarttır.

Keywords

• Müsilaj
• Ötrifikasyon
• Besin girdisi
• Klorofil seviyesi
• Sıcaklık anomalisi
• Akdeniz havzası

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