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An intense proliferation of cyanobacteria in Cabras Lagoon was investigated over a period of two years (July 2007 to June 2009). The influence of environmental and meteorological parameters in the lagoon on temporal variations in cyanobacteria orders was assessed. For 17 months, Chroococcales was the only cyanobacterial order observed in the lagoon. Cyanobium-type cells (Reynolds functional group Z) were the most abundant phytoplankton taxon during this period. In the following months, drastic changes in the cyanobacteria assemblages occurred simultaneously with constant, intense rainfall that led to a sudden drop in the lagoon’s salinity. The succession of autumn–winter Oscillatoriales (Planktothrix sp. and Pseudanabaena catenata; Reynolds functional group S1) and late spring growth of Nostocales (Aphanizomenon gracile, Aphanizomenon aphanizomenoides, and Anabaenopsis circularis; Reynolds functional group H1) was monitored. Canonical Correspondence Analysis was carried out to quantify the influence of environmental variables, and indicated strong relationships between Chroococcales and salinity, Oscillatoriales and higher values of SRP and the DIN/SRP ratio, and Nostocales and lower nutrient concentrations, the DIN/SRP ratio and salinity., Durante dos años (julio 2007-junio 2009) se monitoreó una proliferación intensa de cianobacterias en la laguna de Cabras, así como los parámetros ambientales y climáticos que determinaron sus variaciones temporales. Durante 17 meses, Chroococcales fue el único orden de cianobacterias en la laguna, del cual células similares a Cyanobium (grupo funcional Z según Reynolds) fueron las más importantes en cuanto a abundancia. En los meses siguientes, las cianobacterias sufrieron cambios drásticos, que ocurrieron simultáneamente con lluvia constante e intensa que dio lugar a una caída brusca de la salinidad de la laguna. Se monitoreó también la sucesión de Oscillatoriales en otoño-invierno (Planktothrix sp. and Pseudanabaena catenata; grupo funcional S1 según Reynolds) y el crecimiento en primavera de Nostocales (Aphanizomenon gracile, Aphanizomenon aphanizomenoides, y Anabaenopsis circularis; grupo funcional H1 según Reynolds). Análisis de Correspondencia Canónica permitieron cuantificar la influencia de las variables ambientales, indicando una estrecha relación entre Chroococcales y salinidad, Oscillatoriales y altos niveles de SRP y proporción DIN/SRP, y Nostocales y bajos niveles de nutrientes, proporción DIN/SRP y salinidad.

The Parent Site IT10-Lake ecosystems of Sardinia - Italy consists of six artificial lakes. It has been part of the LTER-Italy since its foundation. The site has been always managed by the University of Sassari, in close collaboration with the Regional Water Authority for lakes in Sardinia (ENAS - Ente Acque della Sardegna). The lakes are located in the north-central part of the Island being Lake Bidighinzu (IT10-001-A), Lake Cedrino (IT10-002-A), Lake Cuga (IT10-003-A), Lake Monte Lerno (IT10-004-A), Lake Sos Canales (IT10-005-A), Lake Temo (IT10-006-A). They have been studied for over thirty years. Since 2006, a Real Time Remote Monitoring System has been operating in each lake. The project aims to provide a tool to optimize the management of the water resource, giving the chance to choose the water layer along the vertical profile from which withdraw the water with the relative best quality for potabilization. Data on water temperature, pH, conductivity, dissolved oxygen and chlorophyll a are acquired by a probe. These data are compared and combined with those obtained in laboratory using standard analysis methods. Long-term series of ecological data are available for each lake, with high-frequency measurements and samplings regarding some of the more important environmental and biological variables. Regarding the LTER Sardinian artificial lakes, their major environmental issue is eutrophication and the related massive growth of phytoplankton. Phytoplankton blooms extensively in summer, largely composed by potentially toxic Cyanobacteria.

The Parent Site consists of two types of aquatic ecosystems: 1. coastal marine ecosystems, i.e. the Gulf of Asinara (IT14-001-A) and the Gulf of Olbia (IT14-002-A). They are respectively localised in the northern and in the north-eastern coast of Sardinia. Different typologies and levels of anthropogenic pressures characterise the two areas (e.g., from protection due to the presence of a National park, to industrial activities and wastewater from urban centres, to agriculture and fisheries, to the tourism). Consequently, they show different environmental scenarios of water quality and environmental concerns; 2. transitional ecosystems, which are three lagoons located along the west-central coast, in the Gulf of Oristano. They are the lagoons of Cabras (IT14-003-A), Santa Giusta (IT14-004-A) and S'Ena Arrubia (IT14-005-A). These research sites are all important wetlands, included in the Ramsar Convention, and identified as IBA (Important Birds Area), SCI (Site of Community Importance) and SPA (Special Protection Areas). The property of the lagoons is of the Autonomous Region of Sardinia. Fisheries and aquaculture are the most important human activities, and also educational and recreational activities are present. The most important environmental issue of these lagoons is eutrophication.

The Parent Site consists of two types of aquatic ecosystems: 1. coastal marine ecosystems, i.e. the Gulf of Asinara (IT14-001-A) and the Gulf of Olbia (IT14-002-A). They are respectively localised in the northern and in the north-eastern coast of Sardinia. Different typologies and levels of anthropogenic pressures characterise the two areas (e.g., from protection due to the presence of a National park, to industrial activities and wastewater from urban centres, to agriculture and fisheries, to the tourism). Consequently, they show different environmental scenarios of water quality and environmental concerns; 2. transitional ecosystems, which are three lagoons located along the west-central coast, in the Gulf of Oristano. They are the lagoons of Cabras (IT14-003-A), Santa Giusta (IT14-004-A) and S'Ena Arrubia (IT14-005-A). These research sites are all important wetlands, included in the Ramsar Convention, and identified as IBA (Important Birds Area), SCI (Site of Community Importance) and SPA (Special Protection Areas). The property of the lagoons is of the Autonomous Region of Sardinia. Fisheries and aquaculture are the most important human activities, and also educational and recreational activities are present. The most important environmental issue of these lagoons is eutrophication.

The Parent Site IT10-Lake ecosystems of Sardinia - Italy consists of six artificial lakes. It has been part of the LTER-Italy since its foundation. The site has been always managed by the University of Sassari, in close collaboration with the Regional Water Authority for lakes in Sardinia (ENAS - Ente Acque della Sardegna). The lakes are located in the north-central part of the Island being Lake Bidighinzu (IT10-001-A), Lake Cedrino (IT10-002-A), Lake Cuga (IT10-003-A), Lake Monte Lerno (IT10-004-A), Lake Sos Canales (IT10-005-A), Lake Temo (IT10-006-A). They have been studied for over thirty years. Since 2006, a Real Time Remote Monitoring System has been operating in each lake. The project aims to provide a tool to optimize the management of the water resource, giving the chance to choose the water layer along the vertical profile from which withdraw the water with the relative best quality for potabilization. Data on water temperature, pH, conductivity, dissolved oxygen and chlorophyll a are acquired by a probe. These data are compared and combined with those obtained in laboratory using standard analysis methods. Long-term series of ecological data are available for each lake, with high-frequency measurements and samplings regarding some of the more important environmental and biological variables. Regarding the LTER Sardinian artificial lakes, their major environmental issue is eutrophication and the related massive growth of phytoplankton. Phytoplankton blooms extensively in summer, largely composed by potentially toxic Cyanobacteria.