Mercury cycling in contaminated coastal environments: modeling the benthic-pelagic coupling and microbial resistance in the Venice Lagoon.

Anthropogenic activities have been releasing mercury for centuries, and despite global efforts to control emissions, concentrations in environmental media remain high. Coastal sediments can be a long-term repository for mercury, but also a secondary source, and competing processes in marine ecosystems can lead to the conversion of mercury into the toxic and bioaccumulative species methylmercury, which threatens ecosystem and human health. We investigate the fate and transport of three mercury species in a coastal lagoon affected by historical pollution using a novel high-resolution finite element model that integrates mercury biogeochemistry, sediment dynamics and hydrodynamics.

Why coastal lagoons are so productive? Physical bases of fishing productivity in coastal lagoons.

Coastal lagoons are among the most productive marine ecosystems in the world. Annual primary production varies from 50 to > 500 g C m year, being of the same order of magnitude as that of the upwelling areas. Many lagoons lie within the range of eutrophic (300-500 g C m year) or hypereutrophic (> 500 g C m year) conditions.

Hot moments and hotspots of cyanobacteria hyperblooms in the Curonian Lagoon (SE Baltic Sea) revealed via remote sensing-based retrospective analysis.

A temporally and spatially detailed historical (1985-2018) analysis of cyanobacteria blooms was performed in the Curonian Lagoon (Lithuania, Russia), the largest coastal lagoon in the Baltic Sea. Satellite data allowed the mapping of cyanobacteria surface accumulations, so-called "scums", and of chlorophyll-a concentration. The 34-year time series shows a tendency towards later occurrence (October-November) of the cyanobacteria scum presence, whereas the period of its onset (June-July) remains relatively constant.

Modelling as decision support for the localisation of submarine urban wastewater outfall: Venice lagoon (Italy) as a case study.

Microbiological impact is critical in coastal areas where tourism is particularly important for both the local and regional economy. Submarine outfalls are commonly used to enhance the dispersion of treated sewage thus avoiding pollution along the coast. The Venice lagoon (North Italy) has a very sensitive ecosystem, due to the morphological and natural characteristics of the basin and the co-existence of human activities.

Natural resources and climate change: A study of the potential impact on Manila clam in the Venice lagoon.

A crucial aspect in climate change is to understand how an ecosystem will adapt under different environmental conditions and how it will influence the ecological resources and the connected human activities. In this study, a numerical model reproduces the growth dynamics, dispersion and settlement of clam's larvae in the Venice lagoon. On the basis of the last IPCC scenarios for the years 2050 and 2100, the model simulates the changes in larval settlement, showing how the geographical distribution and, consequently, the nursery area changes over time.

GIS-based multi-criteria site selection for zebra mussel cultivation: Addressing end-of-pipe remediation of a eutrophic coastal lagoon ecosystem.

Farming of shellfish and seaweeds is a tested tool for mitigating eutrophication consequences in coastal environments, however as many other marine economic activities it should be a subject of marine spatial planning for designating suitable sites. The present study proposes site selection framework for provisional zebra mussel farming in a eutrophic lagoon ecosystem, aimed primarily at remediation purposes. GIS-based multi-criteria approach was applied, combining data from empirical maps, numerical models and remote sensing to estimate suitability parameters.

The Trapping Index: How to integrate the Eulerian and the Lagrangian approach for the computation of the transport time scales of semi-enclosed basins.

In this work, we investigated if the Eulerian and the Lagrangian approaches for the computation of the Transport Time Scales (TTS) of semi-enclosed water bodies can be used univocally to define the spatial variability of basin flushing features. The Eulerian and Lagrangian TTS were computed for both simplified test cases and a realistic domain: the Venice Lagoon. The results confirmed the two approaches cannot be adopted univocally and that the spatial variability of the water renewal capacity can be investigated only through the computation of both the TTS.

Assessing confinement in coastal lagoons.

Measures of transport scale in aquatic systems can contribute to the formulation of definitions of indicators of the system's ecological properties. This paper addresses confinement, a specific transport scale proposed by biological scientists as a parameter that can capture and synthesize the principal properties that determine the spatial structure of biological communities in transitional environments. Currently, there is no direct experimental measure of confinement.

Submarine wastewater discharges: dispersion modelling in the Northern Adriatic Sea.

Background, Aim And Scope: Opposite interests must coexist in coastal areas: the presence of significant cities and urban centres, of touristic and recreational areas, and of extensive shellfish farming. To avoid local pollution caused by treated wastewaters along the Northern Adriatic coast (Friuli Venezia-Giulia and Veneto regions), marine outfall systems have been constructed. In this study, the application of a numerical dispersion model is used to support the traditional monitoring methods in order to link information concerning the hydrodynamic circulation and the microbiological features, to evaluate possible health risks associated with recreational and coastal shellfish farming activities.

Investigation of residence time and groundwater flux in Venice Lagoon: comparing radium isotope and hydrodynamic models.

The four naturally-occurring isotopes of radium were coupled with a previously evaluated hydrodynamic model to determine the apparent age of surface waters and to quantify submarine groundwater discharge (SGD) into the Venice Lagoon, Italy. Mean apparent age of water in the Venice Lagoon was calculated using the ratio of 224Ra to 228Ra determined from 30 monitoring stations and a mean pore water end member. Average apparent age was calculated to be 6.