20 research outputs found
Application of Specific Exergy to Macrophytes as an Integrated Index of Environmental Quality for Coastal Lagoons
No full textThis work aims to explore the application of specific exergy on macrophytes as an
integrated index to assess ecosystem health in coastal lagoons, and to analyse its possible application in view of the implementation of the Water Framework Directive of the European Union. Exergy and specific exergy are calculated as a function of the biomass multiplied by a weighting factor (beta), which express the quantity of information embedded in the biomass. Until now only few general values of beta have been published. Therefore, we have extended the calculation of beta values for 244 seaweed and seagrass species which are common in Mediterranean coastal lagoons. The estimated beta values have been then compared with macrophyte-based indicators which have been recently developed, namely the Ecological Evaluation Index and the IFREMER classification scheme. Overall, we found a good agreement between beta values and macrophyte indicators. Furthermore, the specific exergy was calculated for 81 sites in coastal lagoons of Southern France and compared with existing classification schemes, finding a good agreement between them. As a result, we argue that specific exergy may be used as an integrated index that is able to synthesize and complement existing approaches.JRC.H.5 - Rural, water and ecosystem resource
Coastal Lagoons of Southern Europe: Recent Changes and Future Scenarios
No full textAs a consequence of their location between land and open sea, coastal lagoons are subject to strong anthropogenic pressures due to tourism and/or heavy shellfish/fish farming. Furthermore, they receive fresh water from their catchment areas loaded with urban, agricultural and/or industrial effluents and domestic sewages. These pressures are responsible for important ecosystem alterations i.e. eutrophication, bacterial contamination, algal blooms (toxic or not), anoxia and fish kills. Further, additional problems arise from costal erosion, subsidence and effects related to extreme meteorological events, typical from Mediterranean areas. The development of management tools for coastal lagoons is a complex task requiring interdisciplinary research and active interaction with the end-users. By developing and implementing a set of information tools (Environmental databases, GIS, watershed and lagoon hydrodynamic coupled with biological models), the DITTY project aimed at the development of the scientific and operational bases for a sustained and rational utilisation of the available resources in Southern European lagoons in five case studies: Ria Formosa (Portugal), Mar Menor (Spain), Thau Lagoon (France), Sacca di Goro (Italy) and gulf of Gera (Greece). During this project, a set of scenarios was defined with end-users and stakeholders, addressing issues such as population growth, change in land use or resource exploitation, dredging operations, water reuse etc… whenever appropriate. Effect of climate change is also considered, taking 2015 as time horizon.JRC.H.5 - Rural, water and ecosystem resource
A 3D Hydrodynamic Fate and Transport Model for Herbicides in Sacca di Goro Coastal Lagoon (Northern Adriatic)
No full textSacca di Goro is a shallow coastal microtidal lagoon with a surface area of 26 km2,
and an average depth of about 1.5 m. Fresh water pollutants loads from Po River branches and several drainage canals lead to anthropogenic eutrophication, frequent summer anoxia crises and chemical contamination. Such events not only affect the lagoon ecosystem but also cause serious economic losses, the lagoon being the second producer of clams in Italy. The present work aims at using a fate model coupled with COHERENS 3D hydrodynamic model to simulate and to explain the spatial distribution and temporal variations of s-triazines herbicides in the Sacca di Goro lagoon. The simulation results of spatial and temporal dynamic behaviour of atrazine, simazine and terbuthylazine have been compared with experimental data obtained during an annual monitoring programme.JRC.H.5 - Rural, water and ecosystem resource
Integrated Modelling in Coastal Lagoons: Sacca di Goro Case Study
No full textA coupled 3D hydrodynamic-biogeochemical model was developed and implemented for the Sacca di Goro coastal lagoon. The model considers nutrient and oxygen dynamics in water column and sediments. Amongst the biological elements, phytoplankton, zooplankton, bacteria, Ulva sp. and commercial shellfish (Tapes philippinarum) were taken into consideration. Nutrients fluxes from the watershed and open sea, as well as atmospheric inputs, heat flux, light intensity and wind shear stress at the water surface constituted the model forcing functions. The comparison of numerical results with available measurement data indicated that the model was able to capture the essential dynamics of the lagoon. This model has been also used to estimate clam productivity and its impacts on water quality and lagoon properties.JRC.H.5 - Rural, water and ecosystem resource
Seasonal Variations of Selected Herbicides and Related Metabolites in Water, Sediment, Seaweed and Clams in the Sacca di Goro Coastal Lagoon (Northern Adriatic)
No full textThis study assesses the status of Sacca di Goro coastal lagoon (Northern Adriatic, Italy) with respect to watershed pollution. Because 80% of its watershed is devoted to agriculture applying plant protection products, selected herbicides and their metabolites were found in the water column, sediments (the upper 0-15 cm horizon), and clams (Tapes philippinarum) and macroalgae (Ulva rigida). Five seasonal sampling campaigns were performed from May 2004 to April 2005 and concentrations measured in five stations in the lagoon and six in the watershed. Relatively high concentrations of the s-triazine - terbuthylazine -, urea herbicides - diuron - and alachlor were detected through the year mainly at stations directly influenced by the Po di Volano inflow. The concentrations of products in use follow a clear seasonal pattern with spring peaks. This pattern is also visible in the sediments as well as in biota. Among metabolites, hydroxylated compounds prevailed, often with concentrations greater than those of the parent compounds. For the most part of the year, the concentrations in biota are close to method-based detection limits, with low potential risk for both natural biota and humans.JRC.H.5 - Rural, water and ecosystem resource
The Sacca di Goro lagoon and an arm of the Po River
No full textThe Po di Volano canal–Sacca di Goro lagoon is a small hydrographic system partially located in the southern part of the Po River Delta. The total surface area is 830 km2 for the watershed and 26 km2 for the lagoon, respectively. The watershed is exploited for agriculture, whilst the coastal lagoon is one of the most important European sites for clam (Tapes philippinarum) farming. The lagoon and small inland zones are also included in the Po River Delta Regional Park. Since the mid 1980s, in the Sacca di Goro lagoon abnormal macroalgal blooms occurred, mainly due to the proliferation of the green seaweed Ulva rigida. The enormous macroalgal biomass production was often followed by summer anoxia and dystrophic crises. In this paper, a review of the main studies concerning altered nutrient cycling and water and sediment pollution is presented. Special attention is paid to the discussion of the different aspects of the watershed–coastal lagoon interactions: main features of the watershed and its evolution, anthropogenic pressures, river runoff influence, nutrient and other contaminant cycles, shellfish farming, and macroalgal blooms. Finally, a brief presentation of possible scenarios is given in an ecological economics perspective
An Integrated Modelling Approach for the Management of Clam Farming in Coastal Lagoons
No full textThe development of shellfish farming was analysed with a coupled watershed and 3D biogeochemical model for the Sacca di Goro coastal lagoon (Northern Adriatic Sea, Italy). Sacca di Goro is the second site in Europe for the production of the Manila clam (Tapes philippinarum). Different scenarios were identified and analysed considering business as usual and target policy options. Farming area increases of 15 and 30% were compared with the present situation, considering clam productivity under different environmental conditions, namely with and without macroalgal blooms. Those options were then analysed under different nutrient loadings, depending upon distinct watershed uses, and freshwater delivery from the lagoon catchment under dry, normal and wet climatic conditions. Model simulations indicated that a further increase of clam arming areas, or a more intense exploitation, in the inner zones of the lagoon will increase the risk of anoxia and macroalgal blooms. A significant increase of clam productivity was predicted for a moderate development (up to 15%) of farming activities along the sea-side of the sand barrier. Finally, preliminary simulations evidenced that meteorological conditions can affect clam productivity, especially in dry year due to a shortage of food supply.JRC.H.1 - Water Resource
