Wrack accumulations are a source of nutrients on sandy beaches and host invertebrate species, increasing local biodiversity. The distribution of these important accumulations varies in space and time depending on the environmental conditions of the area and the biological factors of the species that compose it. Consequently, this spatio-temporal variability in the wrack accumulations remains poorly understood in some regions. This database compiles the monthly variability in dry weight biomass of six seaweed taxa(Saccorhiza polyschides, Fucus spp., Ascophyllum nodosum, Cystoseira spp., Ulva spp. and Sargassum muticum) which forming the wrack of four sandy beaches in the northern Portugal (Âncora, Cabedelo, Paramos and São Pedro de Maceda)through a year.

The hypothesis that, temporal variation in nematode abundance, community composition and trophic structure is coupled with changes in the quantity and quality of their potential food sources was tested.

The main aim of the dataset is preparing the available data by diversity and distribution of the Black Sea seagrasses, which were collected the scientists from IBSS around Ukranian and Russian coastal zone during last 50 years (1960 - 2009). The data about region, location, sampling equipment are given for each seagrass species. The species diversity is described from 45 transects, 164 stations at 0,3 - 20 m depth. These data are available now for scientists, professionals and they can be used in various purposes.

Biometric measurements of four colonizing Zostera marina patches in the Mira channel of the Ria de Aveiro from December 2019 to August 2020 Description Biometric measurements of four colonizing Zostera marina patches (shoot density, seagrass coverage, leaf width, number of leaves per shoot and leaf surface area) were taken in the Mira channel of the Ria de Aveiro from December 2019 to August 2020. The seagrass coverage was measured in each patch by recording species presence using a metal frame of 50 × 50 cm divided into 25 sub-quadrats of 10 × 10 cm (n= 4). Shoot density was calcu lated by counting the number of vertical rhizomes of each patch into 4 sub-quadrants per each quadrant of 50 × 50 cm (n=4). Then, shoot density per square meter was calculated. Four shoots per quadrant were selected to measure leaf length, leaf width and the number of leaves per shoot and to calculate leaves per shoot and leaf surface area. Seagrass measurements were always done during low tide periods.

Measurements of trophic markers performed in benthic macrofauna sampled in seagrass litter accumulations from Calvi Bay (Corsica, France) in 2011-2012.

Counts of observed fish species and numerical and gravimetrical stomach analysis for 9 fish species at the West and East creek of Gazi Bay during a 2 day sampling in August 1993. The data were digitized by VLIZ from the original report: De Troch, M. (1995). Gemeenschapsanalyse en trofische organisatie van de ichthyofauna in een tropische baai (Gazi Bay, Kenya; Community analyses and trophic organisation of the ichthyofauna in a tropical bay (Gazi Bay, Kenya). MSc Thesis. Universiteit Gent. Mariene Biologie. Instituut voor Dierkunde. Vakgroep Morfologie, Systematiek en Ecologie: Gent. 136 pp.

Data on <i>Posidonia oceanica</i> collected during spring and summer 2005 in three sites within the Bay of Roses.

<p>Abundance (individual counts) and biomass (g) of macrozoobenthic taxa at soft-bottom stations along the Bulgarian Black Sea coast, collected during a field survey of IBER-BAS in 2022 as part of project BRIDGE-BS (<a href="https://bridgeblacksea.org/">https://bridgeblacksea.org/</a>). The dataset also contains organism life stages, sediment type (Folk16), and EUNIS L3 habitat type at the stations.</p>