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  • The ANT-Biofilm research project (PNRA16_00105) concerned the study of microbial colonization processes in coastal environments of Terra Nova Bay (Ross Sea), through the analysis of the microbial biofilm (bacteria, microalgae) and macrobenthic settlement on plastic substrates, with the aim of determining their possible variations caused by natural or anthropogenic disturbances (variations in salinity or the presence of contaminants, respectively). Microbial biofilms, which play a key role as a substrate for larval settlement of many species of invertebrates, constitute hot-spots of microbial diversity; and it is also known that the communities a microbial are capable of responding rapidly to changing environmental conditions, acting as potential "sentinels" of natural or anthropic perturbations that recently are threatening the Antarctic biota. During the first year of activity (XXXIII Italian expedition, November 2017) stainless steel structures were fixed on the seabed of Road Bay and Tethys Bay mounting panels of artificial substrates (Polyvinyl Chloride, PVC and PolyEthylene, PE) for colonization, which during the XXXIV expedition (November 2018) were retrieved in order to study the fouling formation processes at different levels of biological complexity (from microbial community including bacteria and microalgae to benthic invertebrates) and to evaluate their evolution in two coastal sites differently exposed to natural or anthropogenic forcings.

  • Trophic interactions underlie coexistence mechanisms between species, define the functional role of specie within communities, affect biodiversity and bioaccumulation processes of heavy metal. Sea-ice dynamics, which at Terra Nova Bay is characterized by an extraordinary seasonality, drives interspecific interactions and the exchange of materials between ecosystem compartments. Indeed, the activation of the primary production after sea-ice break up opens alternative trophic pathways for consumers. The “next generation SRPs” represent a highly appropriate framework for the present project which follows the results obtained with the previous project ISOBIOTOX (PNRA 2013) and aims at (i) determine topological and functional metrics of sympagic and pelagic food webs at Terra Nova Bay under different conditions of sea-ice coverage along a distance gradient from the nearest open water polynya to areas were the seasonal sea-ice coverage persists longer; (ii) evaluate bioaccumulation and biomagnification of heavy metals in trophic sources at the base of the food web and in target species along food chains, including fishes of commercial interests and top predators, both in the presence and absence of sympagic and pelagic primary producers. High resolution food webs will be reconstructed by means of the simultaneous elemental and isotopic analysis of different elements (C and N) and the bioaccumulation of pollutants. The research program integrates complementary research approaches: (a) Elemental analysis coupled with mass spectrometry for stable isotope analysis (δ13C, δ15N) in animal and vegetal tissues and dead organic matter, (b)analyses of heavy metals accumulation (Chromatography) in the constituent species of the Antarctic food web.

  • The main goal of our proposal is to characterize the surface radiative budget as well as cloudiness which features at the Argentine Bases Marambio and Belgrano II during the YOPP-SH Special Observing Period (SOP) as well as the YOPP Consolidation Phase. Specific objectives to secure our main goal during the SOP will be: 1 - develop a compact Radiation Measurement UNIT (RMU) robust enough to allow continuous measurements in harsh environment through which to make shortwave, longwave observations as well as to record status of the sky. 2 - secure UV measurements at both stations. 3 - develop specific tools to analyse on a daily basis (weakly for clouds) collected data and extract parameters of interest. For radiation these will include QA/QC SW and LW downwelling and upwelling fluxes, diffuse and direct components of solar radiation, UV spectral flux and doses. For clouds these will include, on a continuous base, cloud fraction derived both from radiometric measurement and sky camera observations, cloud type and cloud effect on SW radiation. In addition cloud base (or cloud ceiling) will be obtained by routine observations performed at the two stations. From UV measurements columnar ozone content will be also derived. Moving forward to YOPP consolidation phase, we plan to: 1 - extend dataset and its analysis, start to collect information on seasonal and inter-annual variability, determine Cloud radiative Forcing (CRF) 2 - perform extensive comparison between automatic and visual cloudiness observation methods. They being very useful to better understand quality and value of historical datasets at the two stationsù 3 - make comparison with cloudiness regime of Ross Sea and Antarctic Plateau. Make similar comparison for UV fluxes in the Peninsula and at Concordia.

  • Categories  

    The geochemical dataset includes: 1. **Soil gas sampling/flux measurements:** Soil gas surveying involves collecting gas samples from the active layer zone to measure the concentrations of various gaseous species in the soil pores. Samples were collected by inserting a steel probe vertically into the soil to a depth ranging from 0.2 m to 0.6 m, depending on the thickness of the active layer. Soil gas samples were taken from the probe using a 60 cc plastic syringe and stored in 15 ml glass vials. The collected gas samples were analyzed with a chromatograph (CP4900 by Varian) to determine the concentrations of the following gaseous species: He, Ne, H2, O2, N2, CH4, C2H2, C2H4, C2H6, CO2, H2S. Radon (222Rn) and Thoron (220Rn) were measured directly in the field using a Durridge RAD7 instrument, performing three or four measurements with a 5-minute integration time. A total of 231 samples were collected during this expedition. Measurements of exhalation flux of CO2 and CH4 from the soil into the atmosphere were conducted using the West System (West Systems TM) accumulation static closed-chamber method. 2. **Continuous monitoring of CO2 concentrations in the active layer:** Continuous monitoring of CO2 concentrations in the bottom of the active layer was recorded. GasPro CO2 Monitoring Probes were designed to measure temperature and CO2 concentration in the unsaturated soil horizon. CO2 concentrations were measured using a Non-Dispersive Infra-Red (NDIR) sensor (model IRCA1 Alphasense). The probes collected one measurement per hour during the period 2020 - 2023 (with gaps) at strategic points within the Taylor and Wright valleys. 3. **Water samples:** We sampled shallow waters from all streams, ponds, and lakes in the studied areas. Physical-chemical parameters such as water temperature, pH, redox potential (Eh), electrical conductivity, and alkalinity were determined in situ. Water samples were collected and stored in high-density polyethylene flasks for laboratory analysis in the following quantities: - 2 flasks of 50 ml for major anions and cations - 1 flask of 50 ml for minor and trace elements - 1 flask of 100 ml for isotopic analyses - 1 serum glass bottle of 155 ml for dissolved gases in the water. Major anions and cations were sampled from filtered and acidified samples, respectively. Minor and trace elements were collected from filtered and acidified samples. An unfiltered sample was collected for the determination of stable isotope analyses (18O, D). The chemical composition analysis of dissolved gases (He, Ne, H2, O2, N2, CH4, CO2), extracted from water samples collected in serum glass bottles and sealed with gas-tight rubber plugs according to the method of Capasso and Inguaggiato (1998), was carried out in the Scott Base Laboratory using an Agilent 4900 CP Micro-gas chromatograph equipped with two TCDs and Ar as carrier gas. The dissolved gas composition (expressed in mmol/L at STP) was calculated from the composition of the exsolved gas phase based on the solubility coefficient of each gas compound (Whitfield, 1978). The analytical error was <5%. A total of 15 water samples were collected during this expedition.

  • The RESTORE project is dedicated to the development of portable robotic technologies with the capability to perform multi-disciplinary multi-parametric 3-D monitoring of marine environment. Its primary focus lies in examining critical areas such as the air-sea-ice and water-sediment interfaces in Antarctica. This endeavour aims to support various research aspects, including the study of microbial ecology and DNA tracing, as well as the investigation of Antarctic geology, particularly the dynamics surrounding glaciers and ice-covered coastal regions. Furthermore, RESTORE is committed to scrutinising the impacts of climate change on the Antarctic atmosphere and the exchanges that occur between the sea and air. The comprehensive dataset collected during RESTORE will provide researchers with a holistic perspective on an extreme and remote environment such as Antarctica, facilitating the interpretation of atmospheric and oceanic dynamics at the interface zones and, the 3D mapping of the underwater environment and the physical characterisation of the sampled region.