AccScience Publishing / AJWEP / Online First / DOI: 10.36922/AJWEP026130082
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ORIGINAL RESEARCH ARTICLE

Assessment of water quality in the coastal wetland of Kalathas, Crete, Greece: A local-scale wetland at high risk

Despoina-Eleni Zacharioudaki1 ,  Ioannis Fitilis1 ,  Eleni Kokinou2 ,  Melina Kotti1*
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1 Department of Electronic Engineering, School of Engineering, Hellenic Mediterranean University, Chania, Crete, Greece
2 Department of Agriculture, School of Agricultural Sciences, Hellenic Mediterranean University, Heraklion, Crete, Greece
AJWEP, 026130082 https://doi.org/10.36922/AJWEP026130082
Received: 23 March 2026 | Revised: 8 May 2026 | Accepted: 8 May 2026 | Published online: 26 May 2026
© 2026 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
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Abstract

Coastal wetlands are highly dynamic ecosystems where natural processes and anthropogenic pressures interact to control water quality. This study evaluates the physicochemical characteristics, nutrient dynamics, photosynthetic pigments, and fluorescence properties of the Kalathas coastal wetland in Crete, Greece, over one year (2022), providing an integrated assessment of its environmental status. The wetland exhibited alkaline conditions and pronounced spatial variability associated with marine intrusion. Among nutrients, silicon showed a strong and consistent positive relationship with chlorophyll a, indicating its key role in regulating phytoplankton biomass. In contrast, total hardness was negatively associated with chlorophyll a, suggesting that increased ionic strength may limit biological productivity. A strong negative relationship between chloride concentrations and fluorescence emission intensity was also observed, consistent with fluorescence quenching under high ionic conditions. Overall, water quality in the wetland appears to be controlled by the combined influence of geological background, marine intrusion, and localized anthropogenic inputs. These findings provide a robust baseline for this understudied ecosystem and highlight the need for continuous monitoring to support effective management and conservation.

Keywords
Coastal wetland
Laser-induced fluorescence
Nutrients
Photosynthetic pigments
Water quality
Funding
This work was implemented in terms of the PhD studies of D-EZ. The publication fee was funded by the Hellenic Mediterranean University and the Public Investment Program of the Greek Ministry of Education and Religious Affairs under the project “Strengthening and optimizing the operation of MODY services and academic and research units of the Hellenic Mediterranean University,” funded.
Conflict of interest
The authors declare they have no competing interests.
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Asian Journal of Water, Environment and Pollution, Electronic ISSN: 1875-8568 Print ISSN: 0972-9860, Published by AccScience Publishing
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