Effect of forced aeration on the biogeochemical cycle of nutrients and metal(loid)s as a remedy for hypoxia in a permanently stratified estuary (Gulf of Trieste, northern Adriatic Sea).

The Timavo River estuary (northern Adriatic Sea) is characterised by strong thermohaline stratification that keeps the deep waters hypoxic. The consequence is an harmful algal bloom at the surface in summer that can be mitigated with a forced aeration system installed at the bottom to improve water oxygenation. The nutrient and metal(loid) cycle was investigated, before and during reoxygenation, using an in situ benthic chamber coupled with sampling and analyses of the water column, sediments and porewater.

Dissolved gaseous mercury production and sea-air gaseous exchange in impacted coastal environments of the northern Adriatic Sea.

The northern Adriatic Sea is well known for mercury (Hg) contamination mainly due to historical Hg mining which took place in Idrija (Slovenia). The formation of dissolved gaseous mercury (DGM) and its subsequent volatilisation can reduce the amount of Hg available in the water column. In this work, the diurnal patterns of both DGM production and gaseous elemental Hg (Hg) fluxes at the water-air interface were seasonally evaluated in two selected environments within this area, a highly Hg-impacted, confined fish farm (VN: Val Noghera, Italy) and an open coastal zone less impacted by Hg inputs (PR: Bay of Piran, Slovenia).

Gaseous mercury evasion from bare and grass-covered soils contaminated by mining and ore roasting (Isonzo River alluvial plain, Northeastern Italy).

High amounts of mercury (Hg) can be released into the atmosphere from soil surfaces of legacy contaminated areas as gaseous elemental mercury (Hg). The alluvial plain of the Isonzo River (NE Italy) suffered widespread Hg contamination due to the re-distribution of Hg-enriched material discharged by historical cinnabar mining at the Idrija mine (Slovenia), but an assessment of Hg releases from the soils of this area is still lacking. In this work, Hg fluxes at the soil-air interface were evaluated using a non-steady state flux chamber coupled with a real-time Hg analyser at 6 sites within the Isonzo River plain.

Gaseous Mercury Exchange from Water-Air Interface in Differently Impacted Freshwater Environments.

Gaseous exchanges of mercury (Hg) at the water-air interface in contaminated sites strongly influence its fate in the environment. In this study, diurnal gaseous Hg exchanges were seasonally evaluated by means of a floating flux chamber in two freshwater environments impacted by anthropogenic sources of Hg, specifically historical mining activity (Solkan Reservoir, Slovenia) and the chlor-alkali industry (Torviscosa dockyard, Italy), and in a pristine site, Cavazzo Lake (Italy). The highest fluxes (21.