The Gulf of Trieste is a semi-enclosed shallow coastal marine ecosystem, whose evolution of biogeochemical properties and productivity is significantly affected by continental and atmospheric inputs of freshwater and nutrients. River loads are the most important source of freshwater in this area, which has reached for Isonzo flows of 1330 m3 s-1 in 2011, as well as a basic source of land borne nutrients and organic matter. Several points of discharge of urban and industrial wastewaters also exist in the gulf, along the coast and through underwater pipelines ending in its central area. Even if their water flows are scarce (' 4 m3 s-1), the associated transport of nutrients and organic matter is not negligible, corresponding to ' 1.4*106 equivalent inhabitants. The direct precipitation over the sea is another mechanism of freshwater and nutrient enrichment poorly quantified, to date. Rain events, in particular during spring and autumn, generate significant freshwater flows (< 83 mm d-1 in 2011). Moreover, considering the possible high concentrations of chemicals in the rainwater in the industrialised country, which originate by anthropogenic emissions, this term might also contribute significantly to the balance of biogenic elements in this coastal zone. During 2011, three oceanographic cruises were carried out in the gulf with R/V Dallaporta (CNR). The acquisition of hydrological data and bottle sampling in 23 stations permitted, for the first time, quasi-synoptic surveys (43-53 hours) representative of an area of about 800 km2 wide, which included both Italian and Slovenian national waters. The balance of freshwater and nutrients performed in this marine area during these cruises was compared to the available information on river transport, wastewater loads and precipitation in order to assess the importance of these external sources for the biogeochemistry of this coastal marine ecosystem.
Importance of allochtonous inputs of freshwater and nutrients in the Gulf of Trieste by the analysis of three quasi-synoptic oceanographic surveys in 2011
Cozzi S;Sparnocchia S;
2013
Abstract
The Gulf of Trieste is a semi-enclosed shallow coastal marine ecosystem, whose evolution of biogeochemical properties and productivity is significantly affected by continental and atmospheric inputs of freshwater and nutrients. River loads are the most important source of freshwater in this area, which has reached for Isonzo flows of 1330 m3 s-1 in 2011, as well as a basic source of land borne nutrients and organic matter. Several points of discharge of urban and industrial wastewaters also exist in the gulf, along the coast and through underwater pipelines ending in its central area. Even if their water flows are scarce (' 4 m3 s-1), the associated transport of nutrients and organic matter is not negligible, corresponding to ' 1.4*106 equivalent inhabitants. The direct precipitation over the sea is another mechanism of freshwater and nutrient enrichment poorly quantified, to date. Rain events, in particular during spring and autumn, generate significant freshwater flows (< 83 mm d-1 in 2011). Moreover, considering the possible high concentrations of chemicals in the rainwater in the industrialised country, which originate by anthropogenic emissions, this term might also contribute significantly to the balance of biogenic elements in this coastal zone. During 2011, three oceanographic cruises were carried out in the gulf with R/V Dallaporta (CNR). The acquisition of hydrological data and bottle sampling in 23 stations permitted, for the first time, quasi-synoptic surveys (43-53 hours) representative of an area of about 800 km2 wide, which included both Italian and Slovenian national waters. The balance of freshwater and nutrients performed in this marine area during these cruises was compared to the available information on river transport, wastewater loads and precipitation in order to assess the importance of these external sources for the biogeochemistry of this coastal marine ecosystem.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
