A Hotspot in the Romanian Black Sea: Eelgrass Beds Drive Local Biodiversity in Surrounding Bare Sediments

Ecosystem engineers create habitat and provide conditions otherwise unavailable for the development of diverse communities. In marine soft-bottoms in particular, the biodiversity sustained by a matrix of relatively uniform sediments can be drastically enhanced by the presence of ecosystem engineers such as seagrasses. Unfortunately, the influence of seagrass meadows on the diversity of surrounding sediments is often unrecognized in spite of its importance, especially in coastlines exposed to multiple sources of pollution. This study examined composition and diversity associated with a bed of Zostera noltei Hornemann, 1832, and its surrounding bare sediments in a highly urbanized coastal area of the Romanian Black Sea. Dissimilarity levels were quantified and key species driving the differences between uniform (bare) and complex (eelgrass) sedimentary habitats were identified. 48 taxa were collected and counted, with epifaunal and infaunal species each accounting for nearly half of that diversity. Abundance, richness and diversity were strikingly higher in eelgrass-associated sediments, a difference driven primarily by various species of snails, crustaceans, polychaetes and bivalves. Between-habitat differences remained significant even after the removal of epifaunal species and each dataset undergoing strong data transformation. These results suggest that even small eelgrass beds, located in the vicinity of multiple sources of stress, can act as hotspots and make a substantial contribution to local benthic diversity.

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Unattached Cystoseira s. l. in the Black Sea: taxonomy of Gongolaria barbata f. repens comb. nov.

Algologia ◽

10.15407/alg31.02.150 ◽

2021 ◽

Vol 31 (2) ◽

pp. 150-162

Author(s):

S.S. Sadogurska ◽

Keyword(s):

Black Sea ◽

Phylogenetic Trees ◽

Morphological Analysis ◽

Taxonomic Status ◽

The Black Sea ◽

Seagrass Meadows ◽

Key Species ◽

The Mediterranean ◽

Morphological Differences ◽

Lateral Branches

Brown algae of the genus Cystoseira s. l. are key species in the Mediterranean basin, including the Black Sea and the Sea of Azov. In addition to the typical attached forms of Cystoseira sensu lato (Ericaria crinita f. bosphorica (Sauvageau) S.S.Sadogurska, J.Neiva et A.Israel, and Gongolaria barbata (Stackhouse) Kuntze), an unattached form was previously described for the Black Sea. The taxonomic status of this taxon remained uncertain. According to the results of a comparative morphological analysis, it is shown that the Black Sea unattached samples belong to the species Gongolaria barbata. But unattached thalli, collected in the Dzharylhach Bay in the seagrass meadows of Zostera marina L., have morphological differences. Thalli are 30–50 cm long, light brown or yellow-brown; the holdfast is absent, the main axis is reduced or, if present, very short and thin (2–4 mm). Lateral branches are thin (2–3 mm), smooth; their length is 15–30 cm. The ultimate branches are filamentous, sometimes with oval-shaped aerocysts, single or arranged in chains. Receptacles are rarely present, spindle-shaped, 8–12 mm in length, without spines, but with a sterile mucron at the end. Therefore, a new nomenclature combination is proposed: Gongolaria barbata f. repens (A.D. Zinova & Kalugina) S.S. Sadogurska comb. nov. It is shown that the nomenclature combination Cystoseira concatenata f. repens A.D.Zinova & Kalugina is invalid. In addition, it is shown that the unattached Gongolaria barbata f. repens is not synonymous with the species Cystoseira aurantia Kützing sensu Orellana et al. (2019), which authors previouslyrearranged to the genus Cystoseira s.s. Analysis of phylogenetic trees from the works by different authors showed that unattached samples from the Mediterranean Sea and the Atlantic Ocean do not belong to the Gongolaria barbata clade and may be unattached forms of other species.

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Variation of carbon contents in eelgrass ( Zostera marina ) sediments implied from depth profiles

Biology Letters ◽

10.1098/rsbl.2018.0831 ◽

2019 ◽

Vol 15 (6) ◽

pp. 20180831 ◽

Cited By ~ 2

Author(s):

Theodor Kindeberg ◽

Emilia Röhr ◽

Per-Olav Moksnes ◽

Christoffer Boström ◽

Marianne Holmer

Keyword(s):

Organic Carbon ◽

Zostera Marina ◽

Large Scale ◽

Environmental Changes ◽

Sediment Cores ◽

Depth Profiles ◽

Seagrass Meadows ◽

Spatio Temporal ◽

Organic Carbon Storage ◽

Eelgrass Beds

Seagrass meadows are able to store significant amounts of organic carbon in their underlying sediment, but global estimates are uncertain partly owing to spatio-temporal heterogeneity between and within areas and species. In order to provide robust estimates, there is a need to better understand the fate of, and mechanisms behind, organic carbon storage. In this observational study, we analyse a suite of biotic and abiotic parameters in sediment cores from 47 different eelgrass ( Zostera marina ) beds spanning the distributional range of the Northern Hemisphere. Depth profiles of particulate organic carbon (POC) revealed three patterns of vertical distribution where POC either increased, decreased or showed no pattern with sediment depth. These categories exhibited distinct profiles of δ 13 C and C:N ratios, where high POC profiles had a proportionally larger storage of eelgrass-derived material whereas low POC profiles were dominated by phytoplanktonic and macroalgal material. However, high POC did not always translate into high carbon density. Nevertheless, this large-scale dataset provides evidence that the variability in organic matter source in response to natural and anthropogenic environmental changes affects the potential role of eelgrass beds as POC sinks, particularly where eelgrass decline is observed.

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Region-wide assessment of the land-based sources of pollution of the black sea

Water Science & Technology ◽

10.2166/wst.1999.0419 ◽

1999 ◽

Vol 39 (8) ◽

pp. 193-200 ◽

Cited By ~ 2

Author(s):

H. Z. Sarikaya ◽

M. F. Sevimli ◽

E. Çitil

Keyword(s):

Black Sea ◽

Oil Pollution ◽

Rapid Assessment ◽

Point Sources ◽

The Black Sea ◽

International Rivers ◽

Sources Of Pollution ◽

River Danube ◽

And Control ◽

Pollution Loads

Black Sea riparian countries have committed to prevent, reduce and control pollution of the marine environment of the Black Sea from land-based sources in accordance with Article VII of the Bucharest Convention. Gathering information on the sources of pollution was one of the basic requirements of the Odessa Ministerial Declaration of the Black Sea countries. This paper presents a summary of the outcome of the studies conducted to fulfil this obligation. The aim of this study has been limited to the point sources of wastewater discharges including domestic as well as industrial discharges. The inputs through main rivers were also included in the scope. Solid wastes directly or indirectly discharged or dumped into the Black Sea were not included in this study. Diffuse sources, surface runoff (storm water) and air emissions were not included in the scope of the study. In this paper, total domestic, industrial and riverine pollution loads of the major pollutants such as BOD, TSS, TN and TP were presented for each of the six Black Sea riparian countries after compilation of the data. Rapid assessment techniques of WHO were adopted in the study to estimate the pollutant loads of the point sources. The major source of contamination to the Black Sea arises as a result of the inputs of contaminants from international rivers, especially the River Danube. The other international rivers are also crucial in the pollution of the Black Sea, although the River Danube is the dominant pollutant source. The fact that the total riverine input is about 85% of the total pollution load of BOD demonstrates the significance of the control of the riverine sources. Total pollution loads of each Black Sea country and their breakdown as domestic, industrial and riverine inputs were presented both in graphical and in tabulated forms. Furthermore, the contribution of the oil pollution and pollution exchange through straits (Kerch and Bosphorus Straits) are also given.

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Estimation of net ecosystem metabolism of seagrass meadows in the coastal waters of the East Sea and Black Sea using the noninvasive eddy covariance technique

Ocean Science Journal ◽

10.1007/s12601-017-0032-5 ◽

2017 ◽

Vol 52 (2) ◽

pp. 243-256 ◽

Cited By ~ 3

Author(s):

Jae Seong Lee ◽

Dong-Jin Kang ◽

Elitsa Hineva ◽

Violeta Slabakova ◽

Valentina Todorova ◽

...

Keyword(s):

Eddy Covariance ◽

Black Sea ◽

Coastal Waters ◽

Ecosystem Metabolism ◽

East Sea ◽

Net Ecosystem Metabolism ◽

Seagrass Meadows ◽

Eddy Covariance Technique

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MODELLING AND SIMULATION OF DISPERSIONS OF POWDER EMISSIONS FROM MULTIPLE SOURCES WITH THE MATHEMATICAL MODEL POL 15SM

Journal of Environmental Engineering and Landscape Management ◽

10.3846/16486897.2013.821068 ◽

2014 ◽

Vol 22 (2) ◽

pp. 151-160

Author(s):

Mihaela Budianu ◽

Valeriu Nagacevschi ◽

Matei Macoveanu

Keyword(s):

Mathematical Model ◽

Air Pollution ◽

Urban Areas ◽

Point Sources ◽

Multiple Point ◽

Multiple Sources ◽

Economic Agents ◽

Sources Of Pollution ◽

Simulation Based ◽

The Mathematical Model

Over the last decades, air pollution has become one of the greatest challenges negatively affecting human health and the entire environment, including air, water, soil, vegetation, and urban areas. Lately, special attention has been given to mathematical modelling for diffusion of pollutants in the atmosphere as a particularly effective and efficient method that can be used to study, control and reduce air pollution. The diversity of models developed by different research groups imposed a rigorous understanding of model types in order to apply them correctly according to local or regional problems of air pollution phenomenon. Tus the authors have developed and improved two mathematical models for dispersion of air pollutants. Tis paper presents a case study of dispersion of powders in suspension originating from 14 point sources that correspond to 5 economic agents in the agroindustrial area of Vaslui city using a computer simulation based on the mathematical model Pol 15sm, for multiple point sources of pollution, designed by the authors.

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Distribution, structure and state of seagrass habitats in the SW Black Sea (Burgas Bay, Bulgaria)

10.7287/peerj.preprints.1141v1 ◽

2015 ◽

Cited By ~ 1

Author(s):

Dimitar Berov ◽

Diana Deyanova ◽

Stefania Klayn ◽

Ventzislav Karamfilov

Keyword(s):

Community Structure ◽

Black Sea ◽

Organic Matter Content ◽

Nutrient Concentrations ◽

The Black Sea ◽

Depth Range ◽

Area Index ◽

Depth Limit ◽

Seagrass Meadows ◽

Distribution Structure

Seagrass habitats play an important role in maintaining the biodiversity and functions of coastal marine ecosystems of the Black Sea. Еutrophication pressures in the 1970s and 1980s had a severe impact on phytobenthic communities, including deterioration, decrease in geographical and depth distribution and disappearance from certain areas. The state of Zostera spp. habitats in the SW Black Sea has not been studied since the 1970s. The purpose of this study is to evaluate the current distribution, structure and overall condition of seagrasses in Burgas Bay, Bulgaria. Historical sites with seagrass meadows were surveyed by SCUBA diving between 2009 and 2014, using destructive sampling and georeferenced digital photogrammetry. Nutrient concentrations in water were measured seasonally at selected sites to study the effects of eutrophication on seagrasses. Seagrass biomass, shoot density, leaf length and leaf area index were measured. Species diversity and biomass of zoobenthic organisms were also determined. Community structure was analyzed with multivariate statistical methods based on photo and destructive samples.The geographical extent of the meadows was mapped in GIS on recent satellite images, then verified by georeferenced photo samples. Results indicate that most of the seagrass meadows reported in the area in the late 1970s are present today. A decrease in the depth limit of the habitat was established in areas under local eutrophication pressures. A clear depth-related change in community structure was observed, where Zostera noltei dominated the 1-3 m depth range, followed by a mixed Z. noltei – Zannichellia palustris - Zostera marina community (3-4 m) , and dominance of Z. marina between 4 and 7 m. Zoobenthic communities within seagrass meadows were dominated by the gastropods Bittium reticulatum and Rissoa sp., the bivalve Loripes lucinalis, and oligochaetes. Abundance and species richness, as well as faunal dominance were significantly higher in seagrass meadows than in adjacent unvegetated sediments. Biometric parameters of Z. noltei showed significant correlations with measured eutrophication pressures (nutrient concentrations, LUSI index, sediment organic matter content). The ecological quality status of selected meadows was evaluated by using a multimeric indicator based on Z. noltei phenology data, which also showed clear correlation with anthropogenic pressures.

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Blue Carbon stock in Zostera noltei meadows at Ria de Aveiro coastal lagoon (Portugal) over a decade

Scientific Reports ◽

10.1038/s41598-019-50425-4 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Ana I. Sousa ◽

José Figueiredo da Silva ◽

Ana Azevedo ◽

Ana I. Lillebø

Keyword(s):

Coastal Lagoon ◽

Large Scale ◽

Management Plan ◽

Blue Carbon ◽

Temporal Shift ◽

Ria De Aveiro ◽

Seagrass Meadows ◽

Zostera Noltei ◽

C Stock ◽

Spatio Temporal

Abstract This work assessed the Blue Carbon (C) stock in the seagrass meadows (Zostera noltei) of Ria de Aveiro coastal lagoon (Portugal), and evaluated its spatio-temporal trend over the 2003–2005 to 2013–2014 period. Zostera noltei spatial distribution, restricted to intertidal areas in 2014, was mapped by remote sensing using an unmanned aerial vehicle (UAV) and aerial photography. Zostera noltei biomass was also monitored in situ over a year and its Blue C stock was estimated. By 2014, intertidal meadows covered an area of 226 ± 4 ha and their Blue C stock ranged from 227 ± 6 to 453 ± 13 Mg C. Overall, Ria de Aveiro Z. noltei intertidal meadows increased in extent over the 2003–2005 to 2013–2014 period, corroborating the recent declining trend reversal observed in Europe and contrary to the global decline trend. This spatio-temporal shift might be related to a natural adjustment of the intertidal meadows to past human intervention in Ria de Aveiro, namely large-scale dredging activities, particularly in the 1996–1998 period, combined with the more accurate assessment performed in 2014 using the UAV. This recovery contributes to the effective increase of the Blue C stock in Ria de Aveiro and, ultimately, to supporting climate regulation and improving ecosystem health. However, major dredging activities are foreseen in the system’s management plan, which can again endanger the recovery trend of Z. noltei intertidal meadows in Ria de Aveiro.

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Current distribution of Zostera seagrass meadows along the Bulgarian Black Sea coast (SW Black Sea, Bulgaria) (2010-2020)

10.3897/arphapreprints.e78947 ◽

2021 ◽

Author(s):

Dimitar Berov ◽

Stefania Klayn ◽

Diana Deyanova ◽

Ventzislav Karamfilov

Keyword(s):

Black Sea ◽

Current Distribution ◽

Satellite Images ◽

Habitat Type ◽

Remote Sensing Data ◽

Scuba Diving ◽

Seagrass Meadows ◽

Black Sea Coast ◽

Current Survey ◽

Sea Coast

The current distribution of Zostera spp. seagrass meadows along the Bulgarian Black Sea coast was studied. We used a combination of historical and recent observations of the habitat along the studied coastline. Remote sensing data (satellite images, sonar side-scans) was groundtruthed with georeferenced drop camera observations, scuba diving sampling and georeferenced scuba diving photo and video transects. Тhe total area of the habitat type ‘MB548 - Black Sea seagrass meadows on lower infralittoral sands’ (EUNIS habitat type list 2019) in the study area is 916.9 ha, of which only 17.9 ha are in man-made sheltered environments (harbours). All seagrass meadows identified in 1978-79 were also located during the current survey, despite the increased eutrophication pressure and overall degradation of benthic habitats in the W Black Sea during the 1980s and early 1990s.

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Spatial patterns of the Zostera noltei meadows across the Atlantic coast of Morocco: is there a latitudinal gradient?

10.7287/peerj.preprints.1076v1 ◽

2015 ◽

Author(s):

Oussama Bououarour ◽

Reda El Kamcha ◽

Loubna Boutahar ◽

Ali Tnoumi ◽

Bendahhou Zourarah ◽

...

Keyword(s):

Average Length ◽

Atlantic Coast ◽

Leaf Length ◽

The Black Sea ◽

Leaf Biomass ◽

North West ◽

Seagrass Meadows ◽

Zostera Noltei ◽

Number Of Leaves ◽

Rhizome Biomass

Seagrass meadows exist in most shallow, sheltered, soft-bottomed marine coastlines and estuaries throughout the world and rank among the most productive systems in the ocean. Zostera noltei Hornemann is a small seagrass largely widespread in intertidal areas of Western Europe and North-West Africa, the Mediterranean Sea and in the Black Sea. In Morocco, intertidal Zostera noltei meadows were identified at six coastal ecosystems across c.a. 2500 km of its Atlantic coast (Tahaddart estuary, Moulay Bousselham, Sidi Moussa, Oualidia, Khnifiss lagoons and Dakhla Bay). The present work aimed at assessing the spatial and latitudinal variation of Z. noltei meadows by measuring the density of shoots, leaf biomass, root-rhizome biomass, number of leaf /shoot and the average length and width of leafs. Samples were conducted between December 2014 and January 2015, using a hand PVC corer (12.5 of diameter). When possible, a downstream and upstream comparison is performed in each site. Density of shoots fluctuated between 1972 and 9833 shoots m-2. Leaves biomass varied between 32 and 259 gDW/m2 and root-rhizome biomass oscillated between 21 and 314 gDW/m2. Number of leaves per shoot fluctuated between 2.47 and 3.4 leaf per shoot, the leaf length between 4.9 and 30.8 cm and the leaf width 0.6 and 2 mm. These results showed, on the one hand, a clear spatial variation across a downstream-upstream gradient in each site and, on the other hand, a latitudinal pattern in the biomass and morphometry of the Z. noltei meadows across the Atlantic coast of Morocco. Significant differences were evidenced for all variables (ANOVA, p<0.05). The root-rhizome biomass and density of shoots are higher southward while the number of leaves per shoot, leaf biomass and the average length and width of the leaves are greater northward. These results are compared with literature data from the distribution range of Z. noltei. Further analysis regarding the genetics, the associated benthic invertebrates and the sediment contamination are being performed and will increase the knowledge on such ecosystems and help in understanding their interaction with environment conditions.

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