Next Article in Journal
Biowaste Valorization Using Hydrothermal Carbonization for Potential Wastewater Treatment Applications
Previous Article in Journal
Wildfire-Induced Changes in Flood Risk in Recreational Canyoning Areas: Lessons from the 2017 Jerte Canyons Disaster
Previous Article in Special Issue
Impact of a Dinophysis acuminata Bloom on the Copepod Acartia clausi: First Indications
 
 
Article

Dumping of Dredge Spoil in the Pelagic Habitat: Focus on Trophic Status, Phytoplankton Diversity Responses and Generation of Blooms

1
Institute of Oceanography, Hellenic Centre for Marine Research HCMR, P.O. Box 713, 19013 Anavyssos, Greece
2
Institute of Marine Biological Resources and Inland Waters, HCMR, 576A Vouliagmenis Ave., 16452 Argyroupoli, Greece
3
Hydrobiological Station of Rhodes, HCMR, Aquarium Square, 85131 Rhodes, Greece
*
Author to whom correspondence should be addressed.
Academic Editors: Jun Yang and Anas Ghadouani
Water 2022, 14(15), 2343; https://doi.org/10.3390/w14152343
Received: 3 June 2022 / Revised: 26 July 2022 / Accepted: 26 July 2022 / Published: 29 July 2022
(This article belongs to the Special Issue Studies on the Diversity and Ecology of Marine Phytoplankton)
This study presents the impacts of dredge spoil dumping in the pelagic habitat during a 27-month monitoring survey in eastern Mediterranean coastal waters (Saronikos Gulf, Aegean Sea), with a focus on changes in trophic status and eutrophication levels, phytoplankton diversity and bloom dynamics. A number of environmental parameters and phytoplankton metrics were significantly influenced by the dumping operations, specifically phytoplankton diversity indices (number of species, Diatoms:Dinoflagellates ratio) and total abundance, Chlorophyll-a, light transmission, dissolved oxygen and inorganic nutrients, N:P ratio, and the Eutrophication Ιndex (a metric for trophic status assessment). Phosphates started to increase after the first year of dumping operations, shifting the N:P ratio to values lower than 10. A similarity cluster analysis highlighted that the phytoplankton community structure during the pre-dumping and the early-dumping period was clearly discriminated from the period during and after the dumping operations. A clear shift with an increase in the Diatoms:Dinoflagellates ratio was observed immediately after the initiation of dumping operations, which maximized in the dumping site after two years of operations. Diatoms dominated the phytoplankton communities, reaching ~ 95% relative abundance in the dumping site. High biomass producers or potentially toxic diatom species proliferated forming blooms. Pseudo-nitzschia multiseries was the most frequent potentially toxic species. A multivariate analysis (RDA) highlighted that among a suite of phytoplankton metrics plotted against stressors relevant to dumping, the Eutrophication Index, Chlorophyll-a, the diversity index Diatoms:Dinoflagellates ratio and the abundance of the potentially toxic diatom P. multiseries emerged as the most suitable to reflect the responses of phytoplankton communities to dumping. Dredge spoil dumping at sea poses pressures to ecosystem components addressed by the European Marine Strategy Framework Directive (MSFD) monitoring programs. In such a context, this study further supports the role of phytoplankton diversity and blooms as sensitive monitoring elements for the environmental status assessment and dumping management in coastal waters. View Full-Text
Keywords: dredging operations; dumping of dredge spoil; phytoplankton diversity; harmful algal blooms HABs; eutrophication; trophic status assessment dredging operations; dumping of dredge spoil; phytoplankton diversity; harmful algal blooms HABs; eutrophication; trophic status assessment
Show Figures

Graphical abstract

MDPI and ACS Style

Varkitzi, I.; Pavlidou, A.; Pantazi, M.; Rousselaki, E.; Hatiris, G.-A.; Gratsia, E.; Kapsimalis, V.; Pagou, K. Dumping of Dredge Spoil in the Pelagic Habitat: Focus on Trophic Status, Phytoplankton Diversity Responses and Generation of Blooms. Water 2022, 14, 2343. https://doi.org/10.3390/w14152343

AMA Style

Varkitzi I, Pavlidou A, Pantazi M, Rousselaki E, Hatiris G-A, Gratsia E, Kapsimalis V, Pagou K. Dumping of Dredge Spoil in the Pelagic Habitat: Focus on Trophic Status, Phytoplankton Diversity Responses and Generation of Blooms. Water. 2022; 14(15):2343. https://doi.org/10.3390/w14152343

Chicago/Turabian Style

Varkitzi, Ioanna, Alexandra Pavlidou, Maria Pantazi, Eleni Rousselaki, Georgios-Angelos Hatiris, Eirini Gratsia, Vasilios Kapsimalis, and Kalliopi Pagou. 2022. "Dumping of Dredge Spoil in the Pelagic Habitat: Focus on Trophic Status, Phytoplankton Diversity Responses and Generation of Blooms" Water 14, no. 15: 2343. https://doi.org/10.3390/w14152343

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop