Marine macrobenthic assemblages off Bevano River mouth (2020)

This dataset provides the abundance (ind. m-2) of marine macrobenthic invertebrate species at 50 random sampling points in a rectangular area of about 1500×600 m from 0.5 to 5.1 m depth, along a beach without bathing establishments in front of the Bevano River mouth, a NATURA 2000 site (IT4070009 "Ortazzo, Ortazzino e Foce del Torrente Bevano") in the Ravenna municipality (Fig. 10), manually sampled from 28 to 29 July, 2020. Depth, sediment grain size, and organic matter at each point are also provided.

The dataset is provided in three formats:

- Microsoft Excel XLSX file, including 3 sheets (Dataset, Fields and units, Taxonomy)

- CSV files (UTF-8), 3 files corresponding to the 3 sheets of the Excel file

- ESRI Shapefile (UTF-8, geometry point, EPSG:4326 - WGS 84)

The dataset includes 50 records, one for each sampling point, and 137 fields (consistent with the other project macrobenthic datasets: Riccione, DOI: 10.5281/zenodo.10592392, and Lido di Dante, DOI: 10.5281/zenodo.10592498). The first 14 fields are described in Table 13. The subsequent fields concern the abundance of the identified taxa as individuals preserved in alcohol sorted and classified under microscope (ind. m-2 ± 20). All the dataset fields are described in the Excel sheet/CSV file “Fields and units”, while the taxonomic related information for each taxon is provided in the Excel sheet/CSV file “Taxonomy”. Information extracted from the World Register of Marine Species (WoRMS; https://marinespecies.org/) is provided here (see details in Table 14). ESRI Shapefile provides users with direct upload in any Geographic Information System (GIS). Nevertheless, due to this file format limitations, dataset field names have been truncated and/or renamed to fit 10 characters.

Figure 10. Map of the study area showing the 50 sampling points (Basemap: Google satellite; Projection WGS84 / UTM 33N, EPSG:32633).

Table 13. First 14 fields in the dataset (NA=not available).

Field

Darwin Core term

Unit

Precision

Note

locationID

locationID

NA

NA

Sampling location identifier (ID) specific to the data set

samplingDate

eventDate

YYYY-MM-DD

NA

Conforms to ISO 8601-1:2019

samplingTime

eventTime

HH:MM

± 10 min

Central European Summer Time CEST (UTC+2) conforms to ISO 8601-1:2019

decimalLatitude

decimalLatitude

decimal degrees

± 0.00001

WGS84 (EPSG:4326) - WAAS/EGNOS enabled GPS position

decimalLongitude

decimalLongitude

decimal degrees

± 0.00001

WGS84 (EPSG:4326) - WAAS/EGNOS enabled GPS position

X_UTM33WGS84

NA

m

± 1

WGS 84 / UTM zone 33N (EPSG:32633) - WAAS/EGNOS enabled GPS position

Y_UTM33WGS84

NA

m

± 1

WGS 84 / UTM zone 33N (EPSG:32633) - WAAS/EGNOS enabled GPS position

Depth

maximumDepthInMeters

m

± 0.1

Mean Sea Level (MSL, Genova zero) - measured with echo sounder and corrected by the closer tide gauge (in the area MSL is about +0.40 MLLW)

SamplingGear

NA

NA

NA

Van Veen grab operated from boat or bailer manually operated by diver inside a cylindrical frame

SamplingArea

NA

m2

± 0.001

Sampler size

Mud

NA

% dry mass

± 0.1%

Sediment particles <63 µ wet sieved recovered on Whatman filter paper and then dried at 80°C for 24 hours before weighing at ± 0.00001 g

FineSand

NA

% dry mass

± 0.1%

Sediment particles 250-63 µ wet sieved recovered on Whatman filter paper and then dried at 80°C for 24 hours before weighing at ± 0.00001 g

MediumSand

NA

% dry mass

± 0.1%

Sediment particles >250 µ wet sieved recovered on Whatman filter paper and then dried at 80°C for 24 hours before weighing at ± 0.00001 g

OrganicMatter

NA

% dry mass

± 0.1%

Sediment organic matter content obtained by Loss of weight on Ignition (LOI%) at 450°C 8h and weighted at ± 0.00001 g

Table 14. Provided taxonomic information.

Taxon

the name used in the dataset

AphiaID_accepted

unique identifier in WoRMS

ScientificName_accepted

the name accepted according WoRMS

Authority_accepted

the name of the scientist or scientists who first validly published the name

Kingdom

Taxonomic level

Phylum

Taxonomic level

Class

Taxonomic level

Order

Taxonomic level

Family

Taxonomic level

Genus

Taxonomic level

Subgenus

Taxonomic level

Species

Taxonomic level

The mouth of the Bevano river is a transition area that boasts great naturalistic and environmental value. The stream, which originates 180 m above sea level, presents one of the last examples of a meandering estuary in the North Adriatic. Located in the province of Ravenna, it is among the best protected transition areas in the Emilia-Romagna region. This is a Site of Community Importance (SCI), Special Protection Area (SPA), Ramsar Zone and Wildlife Protection Oasis. The site is also included among the State Reserves ("Duna costiera ravennate e foce torrente Bevano") and is part of the Po Delta Regional Park ("Pineta di Classe e Saline di Cervia" station).

The mouth of the Bevano river, protected from human disturbance and in particular from that linked to tourism, has been left free to evolve in the coastal system for years. However, in 2006, some manipulative interventions on the morphology of the mouth were necessary and unpostponable to guarantee the conservation of the surrounding habitats. In the thirty years prior to the works, in fact, the mouth of the Bevano torrent had gradually undergone a shift towards the north for reasons linked in part to the phenomenon of subsidence which strongly affects the entire region, and in part to the predominance of long-coast currents and the low-energy river regime. The effects of the migration of the mouth northwards were: a rapid erosion of the pine forest behind and of the dunes north of the mouth and a serious difficulty in disposing of the water towards the sea in periods of river floods with consequent flooding of the surrounding agricultural lands. Thanks to the works carried out in 2006, the original mouth of the river was closed and a new one was dug 600 meters south. Furthermore, the dune was rebuilt to protect the pine forest behind it and a drainage channel was built to guarantee the entry of sea water during the high tides and the exit of the water from the stream during floods.

Here, sampling of the benthic fauna present on the seabed in July 2020 allowed the identification of 86 taxa. The most abundant species were the Lentidium mediterraneum bivalves (on average 3676 ind. m-2) and the Prionospio caspersi polychaete (3368 ind. m-2). Also the Chamelea gallina clam, a bivalve of great commercial interest, was found to be very abundant (559 ind. m-2).

Related Project: TAO (Tecnologie per il monitorAggio cOstiero) project, concerning innovation in shallow-water coastal monitoring (POR FESR 2014-2020 ASSE 1 AZIONE 1.2.2 PROGETTO CUP E31F18001030007; June 2019 - May 2021).