Description: Highlights: • The impact of brine discharge on coastal food-web was modeled. • Stable isotope data validated the simulated trophic structure. • Simulated and observed spatial-temporal biomass trends were comparable. • Simulated outflow brine plumes had limited impact on the food-web. • Temperature had a greater negative impact on biomass than salinity. Abstract: Population growth and climate change have led to an increasing demand for freshwater, and subsequently to an exponential growth of the seawater desalination industry in which the number of reverse osmosis-based plants is constantly increasing. The purpose of this study was to examine the possible impact of brine discharge on the marine food-web by constructing and analyzing food-web models from two desalination plant environments located along the Israeli coastline. The models were constructed using the Ecopath and Ecosim with Ecospace modeling suite, and analyses of collected samples were used for calibration and validation. Additionally, we conducted a series of scenarios in order to evaluate the impact of increased salinity and temperature on the food-web. A comparison between model output and measured isotopic δ15N values yielded a good fit. In addition, Ecopath results illustrated the importance of the zooplankton groups both in terms of biomass and trophic level. Ecospace results indicated that most functional groups biomass decreased compared to the "no desalination" scenario. The results indicate that elevated temperature most likely has a greater effect than increased salinity on the food-web, and that there is a general decrease in functional groups biomass due to desalination.

Description: Highlights: • Zooplankton community structure was sampled in the vicinity of desalination plants. • Taxonomic composition showed seasonality and abundance differences among taxa. • No brine plume visible impact was found on zooplankton abundance and structure. • Abundance estimates correspond well with other recent zooplankton surveys. Abstract: In order to evaluate the impact of desalination facilities on the diversity and abundance of zooplankton, the abundance and structure of the zooplankton community were sampled along the Israeli Levantine shallow coast in the vicinity of desalination facilities. Samples were collected at two sites (Hadera and Ashqelon) during different seasons over a period of 15 months from November 2016 to January 2018. Tows were conducted above bottom depths of 2–28 m with both surface and deeper tows collected during the day and night. Results show a strong seasonality in taxonomic composition and differences in abundance in different taxa groups. There were, however, no differences between day and night, surface and deeper tows, and no impact of the brine plume. Abundance estimates correspond well with other recent studies of zooplankton abundance and community composition in other regions of the Eastern Levantine. This study represents the first quantitative survey of zooplankton conducted along Israeli Levantine shallow coast.

Description: The aim of this work is to present the food web models developed using the Ecopath with Ecosim (EwE) software tool to describe structure and functioning of various European marine ecosystems (eastern, central and western Mediterranean Sea; Black Sea; Bay of Biscay, Celtic Sea and Iberian coast; Baltic Sea; North Sea; English Channel, Irish Sea and west Scottish Sea; and Norwegian and Barents Seas). A total of 195 Ecopath models based on 168 scientific publications, which report original, updated and modified versions, were reviewed. Seventy models included Ecosim temporal simulations while 28 implemented Ecospace spatiotemporal dynamics. Most of the models and publications referred to the western Mediterranean Sea followed by the English Channel, Irish Sea and west Scottish Sea sub-regions. In the Mediterranean Sea, the western region had the largest number of models and publications, followed by the central and eastern regions; similar trends were observed in previous literature reviews. Most models addressed ecosystem functioning and fisheries-related hypotheses while several investigated the impact of climate change, the presence of alien species, aquaculture, chemical pollution, infrastructure, and energy production. Model complexity (i.e., number of functional groups) increased over time. Main forcing factors considered to run spatial and temporal simulations were trophic interactions, fishery, and primary production. Average scores of ecosystem indicators derived from the Ecopath summary statistics were compared. Uncertainty was also investigated based on the use of the Ecosampler plug-in and the Monte Carlo routine; only one third of the reviewed publications incorporated uncertainty analysis. Only a limited number of the models included the use of the ECOIND plug-in which provides the user with quantitative output of ecological indicators. We assert that the EwE modelling approach is a successful tool which provides a quantitative framework to analyse the structure and dynamics of ecosystems, and to evaluate the potential impacts of different management scenarios.

Description: Available information and potential data gaps for non-fish marine organisms (cnidarians, crustaceans, echinoderms, molluscs, sponges, mammals, reptiles, and seabirds) covered by the global database SeaLifeBase were reviewed for eight marine ecosystems (Adriatic Sea, Aegean Sea, Baltic Sea, Bay of Biscay/Celtic Sea/Iberian Coast, Black Sea, North Sea, western Mediterranean Sea, Levantine Sea) across European Seas. The review of the SeaLifeBase dataset, which is based on published literature, analyzed information coverage for eight biological characteristics (diet, fecundity, maturity, length-weight relationships, spawning, growth, lifespan, and natural mortality). These characteristics are required for the development of ecosystem and ecological models to evaluate the status of marine resources and related fisheries. Our analyses revealed that information regarding these biological characteristics in the literature was far from complete across all studied areas. The level of available information was nonetheless reasonably good for sea turtles and moderate for marine mammals in some areas (Baltic Sea, Bay of Biscay/Celtic Sea/Iberian Coast, Black Sea, North Sea and western Mediterranean Sea). Further, seven of the areas have well-studied species in terms of information coverage for biological characteristics of some commercial species whereas threatened species are generally not well studied. Across areas, the most well-studied species are the cephalopod common cuttlefish (Sepia officinalis) and the crustacean Norway lobster (Nephrops norvegicus). Overall, the information gap is narrowest for length-weight relationships followed by growth and maturity, and widest for fecundity and natural mortality. Based on these insights, we provide recommendations to prioritize species with insufficient or missing biological data that are common across the studied marine ecosystems and to address data deficiencies.