Assessment of Aquatic Ecosystems from Coastal Lakes (Agigea, Tuzla, and Costinești)

Authors

  • Ana Bianca Pavel

    National Institute for Research and Development on Marine Geology and Geoecology – GeoEcoMar, 024053 Bucharest, Romania
  • Catalina Gavrila

    National Institute for Research and Development on Marine Geology and Geoecology – GeoEcoMar, 024053 Bucharest, Romania
  • Irina Catianis

    National Institute for Research and Development on Marine Geology and Geoecology – GeoEcoMar, 024053 Bucharest, Romania
  • Gabriel Iordache

    National Institute for Research and Development on Marine Geology and Geoecology – GeoEcoMar, 024053 Bucharest, Romania
  • Catalin Gheablau

    National Institute for Research and Development on Marine Geology and Geoecology – GeoEcoMar, 024053 Bucharest, Romania
  • Florina Radulescu

    National Institute for Research and Development on Marine Geology and Geoecology – GeoEcoMar, 024053 Bucharest, Romania
  • Albert Scrieciu

    National Institute for Research and Development on Marine Geology and Geoecology – GeoEcoMar, 024053 Bucharest, Romania

DOI:

https://doi.org/10.30564/re.v8i1.11099
Received: 16 July 2025 | Revised: 23 August 2025 | Accepted: 26 August 2025 | Published Online: 21 January 2026

Abstract

This study presents an integrated assessment of sedimentological, granulometric, physico-chemical, and biological characteristics in three Romanian coastal lakes, based on 2022 field surveys. A total of 59 sediment samples were analyzed lithologically and granulometrically, and 12 were examined for macrozoobenthic community composition. Water samples were assessed for nutrient and pigment concentrations to evaluate trophic status and ecological condition. Sediments were predominantly silty–clayey, indicating low-energy depositional environments. Organic matter content was highest in Lakes Agigea and Tuzla, suggesting enhanced primary productivity and organic detritus accumulation, while Lake Costinești showed higher biogenic carbonate content from mollusc shells. Macrozoobenthic assemblages were dominated by taxa tolerant to organic enrichment and hypoxia, including Chironomidae larvae, Oligochaeta, and Cyprideis torosa. Water quality analysis indicated good ecological status in Agigea Lake, whereas Tuzla Lake was severely eutrophic, with phosphate and nitrite in Class IV and chlorophyll-a exceeding Class V thresholds (>250 µg/L), consistent with cyanobacterial blooms. Elevated sulfate (Class III) and suspended solids further impaired Tuzla’s transparency. In Costinești, marine taxa presence and variable salinity reflected periodic seawater exchange. Anthropogenic influences were evident—nutrient enrichment from fisheries in Tuzla and marine species introduction in Costinești—highlighting system vulnerability to human pressure. The integration of sediment, water quality, and biological indicators emphasizes the need for continuous, interdisciplinary monitoring to track ecological shifts, support adaptive management, and conserve biodiversity and ecosystem integrity in Romanian coastal lakes.

Keywords:

Coastal Lakes; Sedimentology; Granulometry; Macrozoobenthos; Organic Matter; Anthropogenic Impact; Ecological Assessment; Romanian Black Sea Coast

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How to Cite

Pavel, A. B., Gavrila, C., Catianis, I., Iordache, G., Gheablau, C., Radulescu, F., & Scrieciu, A. (2025). Assessment of Aquatic Ecosystems from Coastal Lakes (Agigea, Tuzla, and Costinești). Research in Ecology, 8(1), 140–168. https://doi.org/10.30564/re.v8i1.11099

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Vol.8, Iss.1 (February 2026)(in progress)

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Article

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Copyright © 2025 Ana Bianca Pavel, Catalina Gavrila, Irina Catianis, Gabriel Iordache, Catalin Gheablau, Florina Radulescu, Albert Scrieciu

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This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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