Hidden ecological risks in reservoir sediments: grain-size dependent enrichment of toxic metals in the black sea basin


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ÖZŞEKER K., TERZİ Y., ERÜZ C., Ismail N. P.

ENVIRONMENTAL GEOCHEMISTRY AND HEALTH, cilt.48, sa.9, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 48 Sayı: 9
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1007/s10653-026-03281-x
  • Dergi Adı: ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, Compendex, EMBASE, Environment Index, Geobase, INSPEC, MEDLINE, Natural Science Collection (ProQuest), Biomedical Reference Collection: Corporate Edition (EBSCO), Earth, Atmospheric, & Aquatic Science Collection (ProQuest), Health Research Premium Collection (ProQuest), Pharma Collection (ProQuest)
  • Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

Toxic metal accumulation in freshwater sediments poses a significant ecological threat, yet bulk sediment approaches often fail to account for particle-size-dependent variability in contamination and risk. This study investigates grain-size-controlled metal enrichment and seasonal dynamics in reservoir sediments from the northeastern Black Sea region (T & uuml;rkiye). Surface sediments collected from the Bor & ccedil;ka, Deriner, and Torul reservoirs were separated into four grain-size fractions (0.063-0.5 mm) and analyzed for Cu, Pb, Zn, Ni, and As. The finest fraction (< 0.063 mm) showed markedly elevated concentrations, reaching up to 409 & micro;g/g for Cu, 156 & micro;g/g for Pb, and 346 & micro;g/g for Zn, substantially exceeding sediment quality guideline thresholds (PEL and ERM in several cases). Metal concentrations consistently decreased with increasing grain size (F1 > F2 > F3 > F4), confirming strong granulometric control. Seasonal patterns revealed higher concentrations in autumn, associated with enhanced fine particle deposition and reduced hydrodynamic conditions. Spatially, the Bor & ccedil;ka reservoir exhibited the highest contamination levels, reflecting the influence of mining-derived inputs and anthropogenic pressures. Importantly, bulk sediment assessments may not fully capture localized metal enrichment associated with fine-grained fractions. These finding demonstrate that integrating grain-size-resolved analysis with ecological risk indices provides a more accurate and environmentally relevant framework for sediment assessment, with important implications for monitoring and management of reservoir ecosystems.