1,721,012 research outputs found
Ecologia e tassonomia delle macrofite degli ambienti marino-costieri e lagunari dell'ecoregione mediterranea
No full textLa ricerca svolta ha permesso di implementare le conoscenze in merito alla diversità macrofitica del Mar Adriatico settentrionale. Nello specifico, si è ottenuta una checklist rappresentativa delle specie presenti nelle quattro stazioni (Salvore, Sistiana, Porto Santa Margherita e Lido) oggetto di studio. Il campionamento tramite quadrato, inoltre, ha permesso di determinare quali specie risultassero dominanti in termini di copertura. I dati delle singole specie e le relative coperture sono quindi stati utilizzati per la valutazione dello Stato Ecologico, attraverso l’applicazione degli indici macrofitici EEI-c (Ecological Evaluation Index) e CARLIT (Cartography of littoral rocky-shore communities). In generale si è rilevato un miglioramento dello Stato Ecologico considerando le stazione da ovest verso est, in contrapposizione con la corrente marina antioraria dell’Adriatico settentrionale. Nello specifico, infatti, dalla zona costiera ad ovest del Po verso la costa croata la classificazione di Stato Ecologico passa da “cattivo” a “alto” con eccezione dell’area antistante la laguna di Venezia, individuata come “moderato”.
Al fine di ottenere una valutazione effettiva sulle criticità e pressioni che influenzano la biodiversità del Mar Adriatico settentrionale, lo studio dei fattori biotici (macrofite) è stato affiancato all’analisi dei parametri abiotici, relativi alla matrice acqua e sedimento. L’analisi statistica effettuata sui dati inerenti la matrice acqua ha, dunque, permesso di evidenziare come le componenti ambientali che maggiormente condizionano le comunità macrofitiche sono la concentrazione dei nutrienti, in modo particolare l’azoto inorganico disciolto, la torbidità e la salinità. In particolare si è determinata una correlazione inversa tra i parametri nutrienti e torbitità rispetto alla salinità: questa evidenza indica chiaramente la forte influenza da parte di imput di acqua dolce di origine fluviale. Tale tesi è inoltre supportata dalla grande variabilità determinata per i parametri ossigeno disciolto (OD), clorofilla-a e pH. I risultati ottenuti mostrano, comunque, come le criticità e le pressioni ambientali non dipendano da un solo limitato ecosistema, ma dall’interconnessione e influenza di molteplici sistemi ambientali come, per esempio, in questo caso, l’ambiente fluviale, lagunare e marino
Macrophyte assemblage composition as a simple tool to assess global change in coastal areas. Freshwater impacts and climatic changes.
No full textMacrophyte assemblages are one of the most sensitive biological communities to assess anthropogenic impacts and climate changes. Community composition responds very quickly to environmental changes driving towards a predictable composition. The increase or decrease of the trophic status (i.e. nutrient concentrations, suspended particulate matter, Chlorophyll-a) and temperature are the most important factors responsible for the replacement of taxa of high ecological value (sensitive taxa) with opportunistic species. A qualitative and quantitative study of macrophytes in 4 areas along the coasts of the Northern Adriatic Sea, from Venice (Italy) to Savudrija (Croatia) and the analysis of river outflows in this region during one year (May 2012–April 2013) provided information about their spatial variability. The coasts of the Veneto Region and Friuli-Venezia Giulia, which are affected by significant freshwater inputs, showed a strong biodiversity reduction or a dominance of thionitrophilic taxa. No seagrasses colonized these areas. On the other hand, the coasts of Croatia had negligible fresh water inputs and macrophyte communities were dominated by sensitive taxa such as the seagrass Cymodocea nodosa and some species belonging to genus Cystoseira
Preliminary results of macrophyte check-list and environmental parameters in some areas of the Northern Adriatic Sea.
Full text linkMacrofite e stato ecologico dell'area individuata per il passaggio delle grandi navi nella laguna di Venezia
No full textMacrophyte distribution and the main ecological parameters of the area between the historical centre of Venice and the industrial area of Porto Marghera were investigated. A map of macrophytes was carried out by sampling 150 sites in July 2015. Four sites were monitored from July to October 2015 by sampling both macrophytes and nutrient concentrations in the water column and surface sediments. The aim was to determine the trophic conditions and the ecological status of that area before the digging of a new canal to create a new access to the large ships that arrive in Venice
Dynamics and drivers of carbon sequestration and storage capacity in Phragmites australis-dominated wetlands
Full text linkCoastal wetlands represent important ecosystems performing several functions leading to services. Out of those, the estimation of carbon sequestration and storage capacity is receiving increasing attention for emissions abatement and climate mitigation. Phragmites australis - dominated wetlands have the capacity to sequester large amounts of carbon given the large biomass formed annually, however the storage capacity depends on various factors including the environmental conditions that are site-specific. The aim of this study was to develop a method that could be used to quantify the storage capacity, from site-specific plant growth drivers (temperature, light, soil nutrients) and environmental attributes (e.g., particle size of soil). This was achieved with a combination of sampling (above- and below-ground plant biomass, nutrients and carbon content, soil nutrients and carbon at different depths) across the whole Venice Lagoon area where P. australis forms habitats under different conditions, using a PCA approach to link biotic and abiotic variables. To upscale the results, a modelling approach in two steps was used, taking first under consideration plant growth under different nutrient availabilities and then simulating the fate of carbon under different conditions (likelihood of material remaining in the area, its decomposition rate, the burial efficiency of soil). The results confirmed a positive effect of nutrient availability, mediated by soil moisture, on plant biomass and storage capacity, in alignment with the model results. Soil type was one the main driver of carbon storage. The knowledge of environmental dynamics and drivers of P. australis - dominated wetlands can be useful to support carbon management in order to mitigate climate change. Our model, with a calibration on different environmental conditions, has the potential to predict carbon sequestration and storage enabling it to be used as a management tool for different ecosystems
Macrophytes and ecological status assessment in the Po delta transitional systems, Adriatic Sea (Italy). Application of Macrophyte Quality Index (MaQI).
Full text linkThe paper provides the first checklist and information on the macrophytes of the Po Delta (Italy),\ud
a complex of small lagoons and ponds among the largest in the Mediterranean Sea, until now little\ud
studied in spite of the water surface of approx. 200 km². The abundance and assemblage composition\ud
of macrophytes that colonize these environments and their ecological status have been studied\ud
taking into account the most common physico-chemical parameters and the concentration of nutrients\ud
in the water column and in the surface sediment.\ud
Sampling was carried out in 17 sites, placed at Marinetta, Vallona, Caleri, Canarin, Barbamarco\ud
and Scardovari lagoons, during two surveys on 13-15 May and 13-15 October 2008. The\ud
ecological status was assessed by applying the Macrophyte Quality Index (MaQI) which was adopted\ud
by the Italian Ministry of the Environment for the ecological classification of the Italian transitional\ud
environments, in agreement with the Water Framework Directive (2000/60/EC) requirements
Macrofite e stato ecologico dell'area individuata per il passaggio delle grandi navi nella laguna di Venezia
No full textMacrophyte distribution and the main ecological parameters of the area between the historical centre of Venice and the industrial area of Porto Marghera were investigated. A map of macrophytes was carried out by sampling 150 sites in July 2015. Four sites were monitored from July to October 2015 by sampling both macrophytes and nutrient concentrations in the water column and surface sediments. The aim was to determine the trophic conditions and the ecological status of that area before the digging of a new canal to create a new access to the large ships that arrive in Venice
Trophic state and ecological status assessment by the application of the CARLIT index in the Northern Adriatic Sea
No full textEnvironmental assessment of marine coastal areas of North-West Adriatic Sea based on Macrophyte Diversity.
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