Connectivity in Three European Coastal Lagoons

Abstract

The temporal variation and the spatial structure of marine populations strongly depend on the early life stages of the individuals and on their interaction with the environment. The physical dispersion of propagules (eggs and larvae) is a fundamental aspect, conditioning the successful recruitment of juveniles in the adult population. Coastal transitional ecosystems such as lagoons plays a role of nursery for species with economic relevance, such as demersal fishes, mollusks and crustaceans. Those environments promote the recruitment of the early stages for several organisms because they act as area of retention for propagules and concentration for resources. We applied in three different European coastal lagoon a lagrangian particle tracking model coupled with a hydrodynamic model, and developed a method to evaluate the connectivity inside a lagoon and between a lagoon and the sea. Each particle represents a generic passive pelagic larva with a duration of one month. The average connectivity has been estimated after two years of simulation under realistic tide and wind forcings. Our results allow to characterize the lagoons behavior considering different spatial scales and to compare the dynamics of different systems. This study is a first step toward a better knowledge of the factors influencing the ecological role of coastal lagoons.

Estuarine circulation in the Taranto Seas

“…Knowledge of these features is not only interesting from a hydrodynamic processes point of view, but it is crucial for understanding the nutrient distribution with its consequences on the trophic net ) and on ecosystem productivity (Cibic et al 2015), as well as to assess the role of the basin in terms of nursery and connectivity (Gulorget and Perthuisot 1992;Belmonte et al 2013;Ghezzo et al 2014). Moreover, because of the Taranto Seas relevance in terms of polluted sediment management, also the circulation effect on the bottom stress was investigated since crucial for studies on sediment transport and on pollutant fate and dispersion processes (Cardellicchio et al 2006;Cardellicchio et al 2015;Di Leo et al 2015;Cassin et al 2015).…”

Bathymetry Time Series Using High Spatial Resolution Satellite Images

“…These percentages have significant seasonal fluctuations depending on the sand deposits caused by the storms in the area and the maintenance work that is carried out regularly on the golas. The water renewal rate of the volume of the Mar Menor lagoon has been calculated as 318 days [27], although this can be very variable depending on the weather conditions and freshwater inputs due to runoff or groundwater discharge [83].…”

“…In this sense, there is a threshold for the magnitude of these activities beyond which important environmental effects can be expected [25,26]. Additionally, the SHYFEM has been used to model environmental parameters such as salinity and temperature [26] as well as the connectivity between the Mar Menor lagoon and the Mediterranean using a Lagrangian model [27,28], so as for predicting the effects of climate change [29].The 3D numerical models need precise and updated initial conditions (Xo, Yo, Zo) to run them [1]. In all the cases, but mainly for applications in coastal zones, the applicability and usefulness of the results are highly dependent on the quality and spatial resolution of the bathymetric information and model grid setup, which determines not only the water column depth, but also information on bed roughness and the incorporation of specific structures and features that affect water and sediment transport dynamics.…”

“…In this sense, there is a threshold for the magnitude of these activities beyond which important environmental effects can be expected [25,26]. Additionally, the SHYFEM has been used to model environmental parameters such as salinity and temperature [26] as well as the connectivity between the Mar Menor lagoon and the Mediterranean using a Lagrangian model [27,28], so as for predicting the effects of climate change [29].…”

On the Calculation of Betweenness Centrality in Marine Connectivity Studies Using Transfer Probabilities

“…Then, the edges between these nodes represent transfer probabilities between these portions of sea. 10 Transfer probabilities estimate the physical dispersion of propagula (Andrello et al 2013;Berline et al 2014); (Jacobi et al 2012;Jonsson et al 2015), nutrients or pollutants (Doglioli et al, 2004), particulate matter (Mansui et al, 2015), or other particles either passive or interacting with the environment (see Ghezzo et al 2015;Bacher et al 2016;and references therein). As a result, graph theory already proved valuable in the identification of hydrodynamical provinces Rossi et al 15 (2014), genetic stepping stones (Rozenfeld et al, 2008), genetic communities (Kininmonth et al, 2010b), sub-populations (Jacobi et al, 2012), and in assessing Marine Protected Areas connectivity (Andrello et al, 2013).…”