The SHAPE Project: An Innovative Approach to Understanding Seasonal and Diel Dissolved Oxygen Dynamics in the Marano and Grado Lagoon (Adriatic Sea) under the WFD/2000/60/CE

Abstract

Dissolved oxygen (DO) is a key element for the survival of marine organisms and is a supporting element in the current Water Framework Directive (WFD). DO deficiency is a common event that occurs in coastal environments such as estuaries and lagoons, but a long-term DO database that helps detect daily and seasonal oscillations is difficult to obtain with commonly used sampling and analytical procedures. In this work, a network of multi-parametric probes was deployed in the Marano and Grado Lagoon (northern Adriatic Sea, Italy) in order to obtain a dataset from the continuous monitoring of DO and complementary parameters. DO showed a high degree of variability both in terms of spatial and seasonal distribution and was dependent on solar radiation and water temperature. During the summer and in areas characterised by scarce water renewal, DO was below the threshold set as the minimum requirement for aquatic life, thus some water bodies (WBs) were classified as moderate sensu WFD. The inputs of freshwater discharge from inland and marine waters during tides are, however, able to well oxygenate most of the lagoon. These results will be useful in supporting the management and protection of this vulnerable environment.

Ecological Effect of Differently Treated Wooden Materials on Microalgal Biofilm Formation in the Grado Lagoon (Northern Adriatic Sea)

“…The lagoon is strongly influenced by semi-diurnal tides, with a mean range of 0.90 m [ 30 ], that act as a forcing factor for the dissolved oxygen content since these tides greatly affect the lagoon hydrodynamics [ 34 ]. The confined area in the easternmost part of the Grado basin is characterised by scarce water exchange and the strong modification of the hydrological regime that occurred as a consequence of a bridge built in 1936 that connects the urban area of Grado to the inland area [ 34 ].…”

“…Based on current velocities [30], two different sites in the Grado basin were selected to run the experiment: "Schiusa" area, an area with higher hydrodynamics (20 cm/s), and "Approdo" area, an area with lower hydrodynamics (10 cm/s) (Figure 1). The lagoon is strongly influenced by semi-diurnal tides, with a mean range of 0.90 m [30], that act as a forcing factor for the dissolved oxygen content since these tides greatly affect the lagoon hydrodynamics [34]. The confined area in the easternmost part of the Grado basin is characterised by scarce water exchange and the strong modification of the hydrological regime that occurred as a consequence of a bridge built in 1936 that connects the urban area of Grado to the inland area [34].…”

UV Absorption Spectrum for Dissolved Oxygen Monitoring: A Low-Cost Proposal for Water Quality Monitoring

“…In other studies, different optical techniques are used to determine DO, such as a polydimethylsiloxane membrane coated with a platinum octaethylporphyrin and a multilayer optical-fluidic sensor for in situ measurement [26,27]. In addition, several authors have developed mechanisms to monitor DO in water as an indicator of the quality and health of aquatic ecosystems [28][29][30].…”

“…In addition, several authors have developed mechanisms to monitor DO in water as an indicator of the quality and health of aquatic ecosystems [28][29][30].…”