Atmospheric and riverine inputs of metals, nutrients and persistent organic pollutants into the lagoon of Venice

Abstract

Atmospheric deposition in the lagoon of Venice and river inputs from the watershed were collected and analysed from 1998 to 1999 using the same analytical methods. The input from riverine sources largely prevails (>70%) over that from the atmosphere for As, Cr, Fe, Mn, Ni, nitrogen and phosphorus. Equivalent amounts of Hg, Pb, PCBs, HCB are discharged into the lagoon from the two sources, whilst atmospheric inputs prevail for Cd, ammonia and dioxins. A comparison with figures of maximum allowable discharges (MAD) for various compounds, recently set by the Italian Ministry for the Environment, showed that total inputs (riverine + atmospheric) of trace metals were below the MAD thresholds only for Cr, Cu, Ni and Zn. The total inputs of Cu and Ni, and Cr and Zn were approximately 20 and 40% of the MAD limit, respectively. The total phosphorus input of 284 t was close to the imposed limit, whilst the inorganic nitrogen load alone (>4000 t) was much higher than the MAD for total nitrogen. For those metals (As, Cd, Hg and Pb) and persistent organic pollutants, such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) where the MAD states that the load should tend to '0Õ (no discharge), the measured inputs of 4.8 (As) and 5.1 t (Pb), 151 (Cd) and 39 kg (Hg), 18 g (PCDD/Fs) and 440 mg (Toxicity Equivalents, TEQs, of PCDD/Fs) are by definition ÔaboveÕ the MAD. The principal component analysis (PCA) of loading data and input profiles (markers) of production typologies showed that river and atmosphere contributions can be easily separated and recognised due to their different fingerprints. Riverine inputs were similar to chemical and glass work production markers, whereas atmospheric loadings were mainly influenced by chemical industry (PVC and VCM production), metallurgy and paper-mill.

Characterisation of PM2.5 concentrations and turbulent fluxes on a island of the Venice lagoon using high temporal resolution measurements

“…Over the last two decades, the decline of the chemical industry and the adoption of new emission control and abatement technologies significantly reduced the aqueous and gaseous industrial emissions in this area (DALLA VALLE et al, 2003). Several studies investigated the levels of atmospheric chemical pollutants in the Venice lagoon, in terms of long-time average (GAMBARO et al, 2004;BETTIOL et al, 2005;ROSSINI et al, 2005) and aerosol concentration and composition (GAMBARO et al, 2007;RAMPAZZO et al, 2008;PRODI et al, 2009;STORTINI et al, 2009) and aerosol deposition , SCAZZOLA et al, 2004GUERZONI et al, 2005;ROSSINI et al, 2005;GAMBARO et al, 2009). This work was focused primarily on the short-term dynamical characteristics of the fine aerosol fraction (PM2.5).…”

Trophic Conditions in the Waters of the Venice Lagoon (Northern Adriatic Sea, Italy)

“…In the most recent years, as a result of both industry decline and the implementation of severe legislation objectives aiming at reducing air and water pollution (Italian Ministerial Decree "Ronchi-Costa decree", April 1998; Italian Ministerial Decree, July 1999), the concentrations of nutrients and of toxic substances in the environment decreased again ( Table 1). At the end of the 1990s, in fact, the nitrate load in the Venice lagoon was estimated to be over 3000 t y -1 (~ 75% from the drainage basin and 25% from atmospheric deposition), the ammonium ~1000 t y -1 (~40% from the drainage basin and 60% from atmospheric deposition), the total phosphorus ~300 t y -1 and the phosphate ~80 t y -1 (80% from the drainage basin and 20% from atmospheric deposition) [15]. During the 1990s also the environmental conditions of the lagoon changed again, as seaweed blooms declined [12,16], mainly because of climatic changes, the increase of sediment re-suspension and the above cited reduction of nutrient loads.…”

“…During the 1990s also the environmental conditions of the lagoon changed again, as seaweed blooms declined [12,16], mainly because of climatic changes, the increase of sediment re-suspension and the above cited reduction of nutrient loads. [14] late 1990s 4000 380 All sources [15] 1999 1050 150 Industrial [13] This paper aims at investigating temporal, seasonal and spatial variations in the lagoon trophic status following the implementation of environmental legislation; this was achieved via the measures of nutrients, chlorophyll a and macrophyte coverage which were carried out once in the whole lagoon and monthly in two stations. This paper would help to draw the evolution of the lagoon environmental conditions through the beginning of the new century.…”

Harmful Elements in Estuarine and Coastal Systems

“…Rossini et al (2010) and Bettiol et al (2005) analyzed the atmospheric bulk deposition of Venice and estimated the metal fluxes to the lagoon. They indicate that industrial sources have a quasi-permanent effect in the composition of atmospheric depositions.…”