Do the levels of industrial pollutants influence the distribution and abundance of dinoflagellate cysts in the recently-deposited sediment of a Mediterranean coastal ecosystem?

Abstract

We studied the relationships between sediment industrial pollutants concentrations, sediment characteristics and the dinoflagellate cyst abundance within a coastal lagoon by investigating a total of 55 sampling stations within the Bizerte lagoon, a highly anthropized Mediterranean ecosystem. The sediment of Bizerte lagoon is characterized by a high dinocyst abundance, reaching a maximum value of 2742 cysts·g −1 of dry sediment. The investigated cyst diversity was characterized by the presence of 22 dominant dinocyst morphotypes belonging to 11 genera. Two dinoflagellate species dominated the assemblage: Alexandrium pseudogonyaulax and Protoperidinium claudicans, representing 29 to 89% and 5 to 38% of the total cyst abundance, respectively, depending on the station. Seven morphotypes belonging to potentially toxic species were detected, including Alexandrium minutum, A. pseudogonyaulax, Alexandrium catenella/tamarense species complex, Lingulodinium polyedrum, Gonyaulax cf. spinifera complex, Prorocentrum micans and Protoceratium reticulatum. Pearson correlation values showed a positive correlation (α = 0.05) between cyst abundance and both water content and fine silt sediment content. Clustering revealed that the highest abundance of cysts corresponds to stations presenting the higher amounts of heavy metals. The simultaneous autoregressive model (SAM) highlighted a significant Contents lists available at ScienceDirectScience of the Total Environment j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / s c i t o t e n v correlation (α = 0.05) between cyst accumulation and two main factors: sediment water content and sediment content for several heavy metals, including Hg, Cd, Cu, Ni and Cr. These results suggest that the degree of heavy metal pollution could influence cyst accumulation patterns.

Dinoflagellate fossils: Geological and biological applications

“…Dinocysts are known to reflect anthropogenic changes and few studies have tried to link dinocyst distribution pattern to different pollution types. Most studies focused on the effect of nutrient enrichment on the dinoflagellate community and the potential of organic-walled dinoflagellates as eutrophication indicators in coastal waters (e.g., Dale and Fjellså, 1994;Dale et al, 1999;Dale, 2001Dale, , 2009Pospelova et al, 2002Pospelova et al, , 2004Matsuoka et al, 2003;Sangiorgi and Donders, 2004;Pospelova and Kim, 2010;Kim et al, 2012;Tian et al, 2018), although few areas were studied testing the effects of industrial pollution (e.g., Saetre et al, 1997;Dale, 2001;Pospelova et al, 2005;Liu et al, 2012;Aydin et al, 2015;Triki et al, 2017). Numerous studies showed that eutrophication signal can be identified by increased dinocyst concentrations in sediments along with nutrient input increases (Dale and Fjellså, 1994;Dale et al, 1999;Matsuoka, 1999;Persson et al, 2000;Pospelova et al, 2005;Rabalais et al, 2009;Liu et al, 2012;Zonneveld et al, 2012).…”

“…Liu et al (2012) showed that autotrophic cysts react more sensitively to industrial pollution than heterotrophic ones, even if the physiological mechanisms behind this difference remain unclear. Some authors then hypothesize that toxic compounds could affect the vegetative cell physiology, inducing a decrease of cell proliferation and an enhancement of cyst production rates so as to survive in unfavorable environmental conditions, with more difficulties to germinate under high metal concentrations in the water column (Lage et al, 1994;Okamoto and Colepicolo, 1998;Godhe and McQuoid, 2003;Leitão et al, 2003;Liu et al, 2012;Herzi et al, 2013, Aydin et al, 2015Triki et al, 2017).…”

Species Assemblages and Distribution of Dinoflagellate Cysts from three Estuaries Sediment’s of Makassar Strait, Eastern Indonesia

“…Several biological and environmental factors: Primary production and physicochemical conditions (e.g., sea-surface temperature and salinity) could control a cysts distribution dynamics (Candel et al, 2012), including physical characteristics of sediment (Anderson et al, 2005;Anglès et al, 2010;Horner et al, 2011). Triki et al (2017) found that fine sediment fractions are affected cyst abundances.…”

Droplet Reactors with Bioluminescent Enzymes for Real-Time Water Pollution Monitoring

“…It is known that heavy metals tend to accumulate in living organisms, leading to various diseases of the nervous, immune, reproductive, and other systems [3,4]. The ions of Pb, Cd, Hg, Cr, As, and Cu are highly toxic pollutants [5,6]. Even a small dose of these substances can have a serious impact on the ecosystem of the water reservoir and its inhabitants, as well as on human health [7].…”