Macrobenthic molluscs from a marine - lagoonal environmental transition in Lesvos Island (Greece).

BACKGROUND: This paper describes an occurence dataset, also including numerical abundance and biomass data, pertaining to the macrobenthic molluscan assemblages from a marine - lagoonal environmental transition. The study system was the soft-substrate benthoscape of the area of the Kalloni solar saltworks (Lesvos Island, Greece). Specifically, the study area extended from the infralittoral zone of the inner Kalloni Gulf (marine habitat) to the bottoms of the first two evaporation ponds of the Kalloni solar saltworks (lagoonal habitat). Bottom sediment samples (3 replicates) were collected with a Van Veen grab sampler (0.1 m2) at four sampling sites, along a 1.5 km long line transect that spanned the marine - lagoonal environmental transition. A total of four surveys were carried out seasonally in 2004.  A total of 39,345 molluscan individuals were sorted out of the sediment samples and were identified to 71 species, belonging to the Gastropoda (36), Bivalvia (34) and Scaphopoda (1) classes. Numerical abundance and wet biomass (with shells) data are included in the dataset. NEW INFORMATION: The dataset described in the present paper partially fills a significant gap in the scientific literature: Because ecological research of coastal lagoons has seldom explicitly considered the marine - lagoonal habitats interface, there are no openly accessible datasets pertaining to the particular structural component of the transitional waters benthoscapes of the Mediterranean Sea. Such datasets could prove valuable in the research of the structure and functioning of transitional waters benthoscapes. The present dataset is available as a supplementary file (Suppl. material 1) and can also be accessed at http://ipt.medobis.eu/resource?r=kalloni_saltworks_phd.

Introduction

Transitional waters (e.g. estuaries, coastal lagoons) may be considered as "ecotone ecosystems" that structurally and functionally link marine, continental and freshwater ecosystems along the coastline (Levin et al. 2001, Basset et al. 2012). Their existence along the interface between the sea and the land determines their abiotic environment, which is characterized by complex spatial gradients in structural features and pronounced temporal variability (Little 2000). The often extreme in magnitude and variability abiotic factors control the composition and spatial distribution of the biota (Barnes 1980, Guelorget and Perthuisot 1992, Barnes 1994).

Macrobenthic invertebrates are considered as a key group among the biota in all coastal aquatic ecosystems (Levin et al. 2001). Molluscs are an important component of the macrobenthic fauna of coastal lagoons (Barnes 1994). Their abundance and diversity are also important in the lower salinity ponds of solar saltworks (e.g. Britton and Johnson 1987, Evagelopoulos et al. 2008, Pavlova et al. 1998, Vieira and Amat 1996), where the habitat is considered to be essentially lagoonal. The response of molluscan communities to the environmental stress gradients has been extensively studied in coastal lagoons (e.g. Guelorget and Perthuisot 1992, Koutsoubas et al. 2000, Reizopoulou and Nicolaidou 2004, Rossi et al. 2006), as well as in the lower salinity ponds of solar saltworks (e.g. Evagelopoulos and Koutsoubas 2008, Evagelopoulos et al. 2008). Ecological research of coastal lagoons has seldom explicitly considered the marine - lagoonal habitats interface (but see de Wit 2011). However, the interfaces between habitat patches are considered to be among the primary structural and functional components of landscapes (Turner and Gardner 2015). Their importance lies in the fact that they may modulate flows of materials, energy, organisms or information across the landscape, potentially also affecting processes inside the interacting habitat patches (Pickett and Cadenasso 1995, Wiens et al. 1985).

This paper describes an occurence dataset, also including numerical abundance and biomass data, pertaining to the macrobenthic molluscan assemblages from the marine - lagoonal environmental transition at the area of Kalloni solar saltworks (Lesvos Island, Greece). The present dataset paper partially fills a significant gap in the scientific literature, as no openly accessible datasets from case studies of marine - lagoonal habitats interfaces have been published thus far and such datasets could prove valuable in the research of the structure and functioning of transitional waters benthoscapes.

General description

Purpose

This dataset was assembled in the framework of the PhD thesis of Dr. Athanasios Evagelopoulos (Department of Marine Sciences, University of the Aegean, Greece) (Evagelopoulos 2008).

Project description

Title

Macrobenthic molluscs from the marine-lagoonal environmental transition at the area of Kalloni saltworks (Lesvos Island, Greece).

Personnel

Drosos Koutsoubas (PhD thesis supervisor, sample collection, taxonomic identification), Athanasios Evagelopoulos (sample collection, taxonomic identification, data management), Vasilis Gerovasileiou (sample collection, laboratory analysis), Nikolaos Katsiaras (sample collection, laboratory analysis), Andreas Alifragkis (sample collection, laboratory analysis), Ioannis Vasiliadis (sample collection, laboratory analysis), Asimenia Kostidou (sample collection).

Study area description

A detailed description of the study area is provided by Evagelopoulos and Koutsoubas (2008) and can be summarized as follows: The study area is characterised by a shallow water column (approx. 0.5 m deep), a soft-substrate bottom and a benthic vegetation of macroalgae and phanerogams (e.g. sp., sp.,  sp., sp.). The habitat types according to the environment ontology of EnvO (Buttigieg et al. 2013, Buttigieg et al. 2016) occuring in the study area included the "neritic sub-littoral zone" (sampling site 1), the "artificial channels" (site 2) and the "lagoons" (sites 3 & 4). Macroalgal mats were developed at the inlet and in the ponds during the late spring - early summer of 2004. Wind forcing together with the shallow depth of the water column were the main factors involved in the recurrent bottom sediment resuspension and the high water turbidity that wereoften observed in the study area. The bottom sediment at the inlet and the ponds was anoxic near its surface, due to the high productivity of the ecosystem. Macroalgal growth led to a dystrophic crisis incident in the study area in the summer of 2004.

Funding

This dataset was assembled in the framework of the PhD thesis of Dr. Athanasios Evagelopoulos, which was supported by a PhD scholarship from HERACLITUS: Research scholarships with priority in basic research (2nd Operational Programme for Education and Initial Vocational Training, 3rd CSF) that was funded by the Greek Ministry of Education and co-funded by the ESF (EU).

Authoring of the present data paper and data management and upload to the MedOBIS IPT were supported by the LifeWatchGreece infrastructure (MIS 384676), funded by the Greek  Government under the General Secretariat of Research and  Technology (GSRT), National Strategic Reference Framework (NSRF).

Sampling methods

Study extent

The study area (Fig. 1) consisted of the soft-substrate benthoscape of the area of the Kalloni solar saltworks (Lesvos Island, Greece). It extended from the infralitoral zone of the inner Kalloni Gulf (marine habitat) to the bottoms of the inlet and the first two evaporation ponds of the Kalloni solar saltworks (lagoonal habitat). The spatial extent of the study was thus approximatelly 1.5 km long, whereas its temporal extent was one year. The geographic coordinates of the sampling sites are given in Table 1.

Figure 1.

A map of the study area, indicating the sampling stations.

Table 1.

Geographic coordinates of the sampling sites.

Sampling site	Site description	Latitude (DD)	Longitude (DD)
1	Kalloni Gulf	39.204974	26.250093
2	Inlet channel	39.207020	26.251612
3	Pond 1	39.209713	26.253069
4	Pond 2	39.208540	26.258517

Sampling description

The field and laboratory methodology used followed the one described by Eleftheriou and Moore (2005). Bottom sediment samples (3 replicates) were collected with a Van Veen grab sediment sampler (0.1 m2 sampling surface area) at four sampling sites that were located along a line transect that spanned the marine-lagoonal environmental transition. The sampling sites (Fig. 1) were located at the infralittoral zone of the inner Kalloni Gulf (site 1), at the inlet channel of the saltworks (site 2) and at the first two evaporation ponds of the saltworks (sites 3 and 4, respectively). The surveys were seasonal and carried out in February, May, September and November of 2004.

Species identification was reviewed by a molluscan taxonomy expert (Prof. Drosos Koutsoubas) and the species names were checked using the Taxon Match tool of the World Register of Marine Species  (http://www.marinespecies.org/aphia.php?p=match). Dimitra Mavraki and Matina Nikolopoulou of the LifeWatchGreece Core Team assisted in the management of data and the upload of the dataset to the MedOBIS IPT according to the DarwinCore schema (DwC).

Step description

After their collection, the sediment samples were washed on-site through a 0.5 mm mesh sieve and subsequently fixed with 5% formalin and stained with Rose Bengal. In the laboratory, the macrobenthic invertebrates were sorted out of the sediment, and classified first into families and then into species. The individuals of each species in each sample were enumerated and their total wet weight (with shells) was measured with a high precision (0.1 mg) balance. During the data management process, the species names were checked with WoRMS, the dataset was prepared according to the Darwin Core standard and, finally, the data were uploaded to the MedOBIS IPT.

Geographic coverage

Description

The geographic coverage of the dataset extends from the part of the inner Kalloni Gulf that is adjacent to the Kalloni solar saltworks to the first two evaporation ponds of the saltworks. A map of the study area is given in Fig. 1 and the geographic coordinates of the sampling sites are given in Table 1.

Coordinates

39.2 and 39.22 Latitude; 26.23 and 26.27 Longitude.

Taxonomic coverage

The taxonomic coverage of the dataset is limited to the molluscan assemblages of the study area. Specifically, the dataset includes gastropod, bivalve and scaphopod species. A list of the species included in the dataset, also indicating their taxonomic classification, is given in Table 2.

Table 2.

List of species included in the dataset, indicating their taxonomic classification.

Scientific name	Authority	Class	Family
Abra segmentum	(Récluz, 1843)	Bivalvia	Semelidae
Axinulus croulinensis	(Jeffreys, 1847)	Bivalvia	Thyasiridae
Cerastoderma glaucum	(Bruguière, 1789)	Bivalvia	Cardiidae
Chamelea gallina	(Linnaeus, 1758)	Bivalvia	Veneridae
Clausinella fasciata	(da Costa, 1778)	Bivalvia	Veneridae
Corbula gibba	(Olivi, 1792)	Bivalvia	Corbulidae
Ctena decussata	(O. G. Costa, 1829)	Bivalvia	Lucinidae
Lucinella divaricata	(Linnaeus, 1758)	Bivalvia	Lucinidae
Donacilla cornea	(Poli, 1791)	Bivalvia	Mesodesmatidae
Donax venustus	Poli, 1795	Bivalvia	Donacidae
Gouldia minima	(Montagu, 1803)	Bivalvia	Veneridae
Irus irus	(Linnaeus, 1758)	Bivalvia	Veneridae
Loripes lucinalis	(Lamarck, 1818)	Bivalvia	Lucinidae
Loripinus fragilis	(Philippi, 1836)	Bivalvia	Lucinidae
Gibbomodiola adriatica	(Lamarck, 1819)	Bivalvia	Mytilidae
Modiolus barbatus	(Linnaeus, 1758)	Bivalvia	Mytilidae
Montacuta substriata	(Montagu, 1808)	Bivalvia	Montacutidae
Musculus sp.	Röding, 1798	Bivalvia	Mytilidae
Myrtea spinifera	(Montagu, 1803)	Bivalvia	Lucinidae
Kurtiella bidentata	(Montagu, 1803)	Bivalvia	Montacutidae
Parvicardium exiguum	(Gmelin, 1791)	Bivalvia	Cardiidae
Pholas dactylus	Linnaeus, 1758	Bivalvia	Pholadidae
Pitar rudis	(Poli, 1795)	Bivalvia	Veneridae
Solen marginatus	Pulteney, 1799	Bivalvia	Solenidae
Polititapes aureus	(Gmelin, 1791)	Bivalvia	Veneridae
Ruditapes decussatus	(Linnaeus, 1758)	Bivalvia	Veneridae
Moerella donacina	(Linnaeus, 1758)	Bivalvia	Tellinidae
Tellina planata	Linnaeus, 1758	Bivalvia	Tellinidae
Tellina sp.	Linnaeus, 1758	Bivalvia	Tellinidae
Tellina tenuis	da Costa, 1778	Bivalvia	Tellinidae
Thracia phaseolina	(Lamarck, 1818)	Bivalvia	Thraciidae
Thyasira flexuosa	(Montagu, 1803)	Bivalvia	Thyasiridae
Timoclea ovata	(Pennant, 1777)	Bivalvia	Veneridae
Venus casina	Linnaeus, 1758	Bivalvia	Veneridae
Acteon tornatilis	(Linnaeus, 1758)	Gastropoda	Acteonidae
Barleeia unifasciata	(Montagu, 1803)	Gastropoda	Barleeiidae
Bela nebula	(Montagu, 1803)	Gastropoda	Mangeliidae
Bittium reticulatum	(da Costa, 1778)	Gastropoda	Cerithiidae
Cerithiopsis sp.	Forbes & Hanley, 1850	Gastropoda	Cerithiopsidae
Cerithiopsis tubercularis	(Montagu, 1803)	Gastropoda	Cerithiopsidae
Cerithium vulgatum	Bruguière, 1792	Gastropoda	Cerithiidae
Chrysallida sp.	Carpenter, 1856	Gastropoda	Pyramidellidae
Circulus sp.	Jeffreys, 1865	Gastropoda	Tornidae
Cyclope neritea	(Linnaeus, 1758)	Gastropoda	Nassariidae
Ebala pointeli	(de Folin, 1868)	Gastropoda	Pyramidellidae
Epitonium clathrus	(Linnaeus, 1758)	Gastropoda	Epitoniidae
Gibbula albida	(Gmelin, 1791)	Gastropoda	Trochidae
Gibbula ardens	(Salis Marschlins, 1793)	Gastropoda	Trochidae
Hydrobia acuta	(Draparnaud, 1805)	Gastropoda	Hydrobiidae
Mangelia attenuata	(Montagu, 1803)	Gastropoda	Mangeliidae
Nassarius incrassatus	(Strøm, 1768)	Gastropoda	Nassariidae
Megastomia conoidea	(Brocchi, 1814)	Gastropoda	Pyramidellidae
Potamides conicus	(Blainville, 1829)	Gastropoda	Potamididae
Pusillina marginata	(Michaud, 1830)	Gastropoda	Rissoidae
Pusillina radiata	(Philippi, 1836)	Gastropoda	Rissoidae
Raphitoma echinata	(Brocchi, 1814)	Gastropoda	Raphitomidae
Rissoa guerinii	Récluz, 1843	Gastropoda	Rissoidae
Rissoa monodonta	Philippi, 1836	Gastropoda	Rissoidae
Rissoa membranacea	(J. Adams, 1800)	Gastropoda	Rissoidae
Rissoa lia	(Monterosato, 1884)	Gastropoda	Rissoidae
Rissoa splendida	Eichwald, 1830	Gastropoda	Rissoidae
Rissoa variabilis	(Von Mühlfeldt, 1824)	Gastropoda	Rissoidae
Rissoa ventricosa	Desmarest, 1814	Gastropoda	Rissoidae
Tricolia pullus	(Linnaeus, 1758)	Gastropoda	Phasianellidae
Monophorus perversus	(Linnaeus, 1758)	Gastropoda	Triphoridae
Trophonopsis muricata	(Montagu, 1803)	Gastropoda	Muricidae
Truncatella subcylindrica	(Linnaeus, 1767)	Gastropoda	Truncatellidae
Turbonilla delicata	Monterosato, 1874	Gastropoda	Pyramidellidae
Turbonilla lactea	(Linnaeus, 1758)	Gastropoda	Pyramidellidae
Pyrgostylus striatulus	(Linnaeus, 1758)	Gastropoda	Pyramidellidae
Fustiaria rubescens	(Deshayes, 1825)	Scaphopoda	Fustiariidae

The distribution of species number in the bivalve and gastropod families is presented in Fig. 2 and Fig. 3 respectively.  (Deshayes, 1825), which belongs to the family, is the only species of tusk shells included in the dataset.

Figure 2.

Distribution of species number in the bivalve families.

Figure 3.

Distribution of species number in the gastropod families.

Temporal coverage

Single date: 2004 2 24; 2004 5 28; 2004 9 17; 2004 11 27.

Notes

The dataset has a temporal coverage of one year (2004): The surveys were seasonal and carried out in Winter (24/2), Spring (28/5), Summer (17/9) and Autumn (27/11).

Usage rights

Use license

Open Data Commons Attribution License

Data resources

Data package title

Spatial and seasonal variability of the molluscan macrofauna at the marine-lagoonal environmental gradient at Kalloni saltworks (Lesvos Island, NE Aegean Sea, Greece)

Resource link

http://ipt.medobis.eu/resource?r=kalloni_saltworks_phd

Number of data sets

1

Data set 1.

Data set name

Spatial and seasonal variability of the molluscan macrofauna at the marine-lagoonal environmental gradient at Kalloni saltworks (Lesvos Island, NE Aegean Sea, Greece)

Number of columns

41

Description

The dataset includes two files: Events and Occurences. The former contains the information on the sampling design, whereas the latter contains primarily the species abundance, biomass and taxonomy information.

Additional information

Resource citation

Evagelopoulos A (2015): Spatial and seasonal variability of the molluscan macrofauna at the marine-lagoonal environmental gradient at Kalloni saltworks (Lesvos Island, NE Aegean Sea, Greece). v1.7. Hellenic Center for Marine Research. Dataset/Samplingevent. http://ipt.medobis.eu/resource?r=kalloni_saltworks_phd&v=1.7

Abundance and biomass variability

The contributions of the most important species in the mean total abundance (ind./sample) for each site and seasonal survey are given in Fig. 4​.

Figure 4.

Contributions of the most important species in the mean total abundance (ind./sample) for each site (1, 2, 3, 4) and seasonal survey (WI: winter, SP: spring, SU: summer, AU: autumn).

The most important species in terms of abundance were selected as the ones contributing in at least 10% of the total mean abundance in a dataset sample.

The most important species in terms of abundanceduring all surveys, were the cerithiid gastropod  at site 2 and the mud snail at sites 3 and 4.

The contributions of the most important species in the mean total biomass (g/sample) for each site and seasonal survey are presented in ​Fig. 5.

Figure 5.

Contributions of the most important species in the mean total biomass (g/sample) for each site (1, 2, 3, 4) and seasonal survey (WI: winter, SP: spring, SU: summer, AU: autumn) .

The most important species in terms of biomass were selected as the ones contributing in at least 10% of the total mean biomass in a dataset sample.

In terms of biomass, the most important species at site 2 was, during all surveys, the cerithiid gastropod whereas the most important species at sites 3 and 4  were, during all surveys, the bivalves and and the gastropods and .

Observed species diversity variability

The spatial variability of the observed species diversity and eveness during each seasonal survey are given in Figs 6, 7, 8, 9.

Figure 6.

Variability of the observed species diversity and eveness along the sites (1, 2, 3, 4) transect during the winter (WI) survey. Diversity was measured using the Hill numbers N0, N1 and N2, whereas eveness was measured with the F2/1 index.

Figure 7.

Variability of the observed species diversity and eveness along the sites (1, 2, 3, 4) transect during the spring (SP) survey. Diversity was measured using the Hill numbers N0, N1 and N2, whereas eveness was measured with the F2/1 index.

Figure 8.

Variability of the observed species diversity and eveness along the sites (1, 2, 3, 4) transect during the summer (SU) survey. Diversity was measured using the Hill numbers N0, N1 and N2, whereas eveness was measured with the F2/1 index.

Figure 9.

Variability of the observed species diversity and eveness along the sites (1, 2, 3, 4) transect during the autumn (AU) survey. Diversity was measured using the Hill numbers N0, N1 and N2, whereas eveness was measured with the F2/1 index.

Observed species diversity was measured with the Hill numbers (Hill 1973 ) N0 (= species richness), N1 (= the exponential form of the Shannon-Wiener entropy index) and N2 (= the reciprocal form of the Simpson concentration index), whereas eveness was measured using the F2/1 eveness index (Alatalo 1981), a transformation of the N2/1 eveness index of Hill (Hill 1973). All the aforementioned indices have several desirable properties and are preferable to the classic diversity (e.g. the Shannon-Wiener index) and eveness (e.g. the Pielou index) indices (Jost 2006, Tuomisto 2010, Tuomisto 2012).

The maximum observed species richness (N0 index) was measured either at site 1, 2 or 3, depending on the season, whereas the minimum was invariably measured at site 4. The minimum observed diversity (N1, N2 indices) was invariably recorded at site 2, due to the minimum of eveness measured therein (F2/1 index).

The dataset

Data type: abundance, biomass and taxonomic classification

Brief description: The dataset file includes the abundance (ind./sample), wet biomass with shells (g/sample) and taxonomic classification of the species in each sample.

File: oo_108852.xlsx

Rank	Scientific Name	Common Name
phylum	Mollusca	Molluscs
class	Gastropoda	Gastropods
class	Bivalvia	Bivalves
class	Scaphopoda	Tusk shells

Data set 1.

Column label	Column description
eventID	An identifier for the set of information associated with an Event (something that occurs at a place and time).
samplingProtocol	The name of, reference to, or description of the method or protocol used during an Event.
sampleSizeValue	A numeric value for a measurement of the size (time duration, length, area, or volume) of a sample in a sampling event.
sampleSizeUnit	The unit of measurement of the size (time duration, length, area, or volume) of a sample in a sampling event.
eventDate	The date-time or interval during which an Event occurred.
year	The four-digit year in which the Event occurred, according to the Common Era Calendar.
month	The ordinal month in which the Event occurred.
day	The integer day of the month on which the Event occurred.
habitat	A category or description of the habitat in which the Event occurred.
fieldNumber	An identifier given to the event in the field.
locationID	An identifier for the set of location information.
locality	The specific description of the place.
minimumDepthInMeters	The lesser depth of a range of depth below the local surface, in meters.
maximumDepthInMeters	The greater depth of a range of depth below the local surface, in meters.
locationRemarks	Comments or notes about the Location.
decimalLatitude	The geographic latitude (in decimal degrees, using the spatial reference system given in geodeticDatum) of the geographic center of a Location. Positive values are north of the Equator, negative values are south of it.
decimalLongitude	The geographic longitude (in decimal degrees, using the spatial reference system given in geodeticDatum) of the geographic center of a Location. Positive values are east of the Greenwich Meridian, negative values are west of it.
coordinateUncertaintyInMeters	The horizontal distance (in meters) from the given decimalLatitude and decimalLongitude describing the smallest circle containing the whole of the Location.
institutionCode	The name (or acronym) in use by the institution having custody of the object(s) or information referred to in the record.
collectionCode	The name, acronym, coden, or initialism identifying the collection or data set from which the record was derived.
basisOfRecord	The specific nature of the data record.
occurenceID	An identifier for the Occurrence.
catalogNumber	An identifier for the record within the data set or collection.
individualCount	The number of individuals represented present at the time of the Occurrence.
organismQuantity	A number or enumeration value for the quantity of organisms.
organismQuantityType	The type of quantification system used for the quantity of organisms.
lifeStage	The age class or life stage of the biological individual(s) at the time the Occurrence was recorded.
identifiedBy	A list (concatenated and separated) of names of people, groups, or organizations who assigned the Taxon to the subject.
scientificNameID	An identifier for the nomenclatural (not taxonomic) details of a scientific name.
scientificName	The full scientific name, with authorship and date information if known.
kingdom	The full scientific name of the kingdom in which the taxon is classified.
phylum	The full scientific name of the phylum or division in which the taxon is classified.
class	The full scientific name of the class in which the taxon is classified.
order	The full scientific name of the order in which the taxon is classified.
family	The full scientific name of the family in which the taxon is classified.
genus	The full scientific name of the family in which the taxon is classified.
subgenus	The full scientific name of the subgenus in which the taxon is classified.
specificEpithet	The name of the first or species epithet of the scientificName.
scientificNameAuthorship	The authorship information for the scientificName formatted according to the conventions of the applicable nomenclaturalCode.
nomenclaturalCode	The nomenclatural code (or codes in the case of an ambiregnal name) under which the scientificName is constructed.
taxonRemarks	Comments or notes about the taxon or name.