AMBIEnCE project aims at assessing the impact of atmospheric organic aerosol (OA) deposition on the molecular composition and reactivity of dissolved organic matter (DOM) in different coastal marine systems. AMBIEnCE also aims at exploring how the intrinsic chemical features of both OA and DOM drive the solubility and bioavailability of atmospheric-derived trace metals (TM) in seawater. Air particles deposition is an important source of new organic and inorganic nutrients, and potentially toxic TM to seawater. These atmospheric multi-stressors are delivered in very different chemical forms and amounts, impacting the marine DOM pump in ways still poorly understood. The extent to which OA and DOM modify the solubility/bioavailability of atmospheric TM are also unknown due to practical difficulties in studying post-depositional processes.
AMBIEnCE is a high-risk/high-gain project that offers a unique approach to assess the impact of atmospheric organic and inorganic particles deposition on the functioning of two coastal marine systems which are influenced by different atmospheric inputs, variable in time and intensity: Ria de Aveiro and Tagus Estuary. The first stage entails the collection of air particles and seawater at both sites in order to unravel the structural features of OA and marine DOM, and TM content in aerosols and seawater. Afterwards, aerosol seeding experiments in lab-made microcosms will be carried out aiming at mimic natural and anthropogenic OA inputs to surface seawater. This aims at capturing changes in OA composition settling through water column and their effect on marine DOM and TM composition/persistent. These trials will be used to assess the effect of two estuarine species (juvenile seabass & polychaetes) on marine DOM and TM content and composition, and evaluate the distribution and toxicity effects of atmospheric TM in the selected species.
The novelty of AMBIEnCE lies on the use of microcosms to accurately study over time, the effect of potential internal (estuarine species) and external (OA inputs) drivers on DOM and TM composition using real biogeochemical assemblages. Results of this project will provide in-depth knowledge on the chemical features and sources of OA and TM arriving at the marine sites, and explain how these atmospheric multi-stressors impact DOM composition and TM solubility/bioavailability. At long term, innovation created by AMBIEnCE will be maximized in a roadmap so that dissemination of foreground results to society can be optimized. To attain its goals, AMBIEnCE brings together a multidisciplinary team of analytical & environmental chemists and geochemists, with expertise in advanced analytical techniques for profiling complex matrices, and biologists with expertise in environmental toxicology, all from University of Aveiro, and a biochemist from NOVA.ID.FCT with expertise in environmental proteomics.