Italiano - University TS - Biology - Research

ECOLOGY: Water ecology - Botany

Endoliths of calcareous algae

Study of marine endolithic micro-organisms which live in calcareous algae, excavating tunnels in the calcified cell walls. These organisms, already described in corals, mollusc shells and inorganic substrata, have so far never been described in detail in red calcareous algae.

Main projects:
  1. Ultrastructural observation, using transmission and scanning electron microscopy, of the organisms found so far in the Gulf of Trieste.
  2. Ecological study arising from the fact that these micro-organisms function as pollution bioindicators and as indicators of the marine photic zone, since some of them are more sensitive than others to the shortage of light.
  3. Study of their relationship with living and dead calcareous algae and of their possible pathogenicity.
  4. Verification of the presence of these organisms in other seas of the Italian coast. Collaboration with Dr. Le Campion-Alsumard of the University of Marseilles.

Scientist in charge: L. A. Ghirardelli.

ECOLOGY: Water ecology - Botany

Algal biofilms and antifouling

Choice of biotoxic antifouling compounds (sodium hypochlorite and chlorine dioxide) and optimisation of dosage (identification of lethal doses, species-specific and bioaccumulative) inside sea water ducts for industrial plant cooling, as simulated in the laboratory.
Qualitative-quantitative methods of analysis of the colonisation dynamics of microbenthic algae populations (in particular diatomeae) in toxic environment are applied, with probabilistic, predictive (multivariate analysis) evaluations of the ultimate effects of the treatment.
The results obtained after five years of research have allowed reduction of the chloride dioxide dosage, with equal effectiveness but less stress to the environment. This research is carried out in collaboration with the research laboratories of the Caffaro Chemical Industries of Brescia.
Mention must be made of the close collaboration with Prof. Laura Talarico for the cytochemical study in cultures of organisms involved in the formation of fouling, in order to perfect applicative prevention techniques.

Scientist in charge: G. Bressan.

ECOLOGY: Water ecology - Botany

Primary productivity on submerged artificial reefs

This research is part of an operation co-ordinated by the European Artificial Reef Project (headed by A.Jensen, UK) aimed at studying the dynamics of plant colonisation of artificial substrates, in relation to the main environmental parameters and at overcoming the project limitations of artificial barriers. Optimisation of the vegetal settlement (primary productivity) and orientation of the development of the vegetal component towards phytophagic ichthyo-fauna, at the same time saving the phytal mantle from the predatory action of sea-urchins. Underwater phytosociologic surveys have highlighted the incidence of the variations in transparency on the dynamics of colonisation, as well as the incidence of grazing; The "anti-urchin nets" of Trieste and Loano (Liguria) seem to have produced satisfactory results. Collaborations: M.R.A.A.F., Laboratory of Marine Biology and Animal Ecology of the Institute of Zoology of the University of Genoa, Scuba-diving Unit of the Corps of Carabinieri.
To be mentioned is the close collaboration with Prof. Laura Talarico in relation to the fine characterisation of the algae biomass involved in energy transfer processes (physiological, morphological and biochemical characterisation: photosynthetic pigments, proteins, etc.).

Scientists in charge: G. Bressan, A. Falace, E. Vio.

ECOLOGY: Water ecology - Botany

Adaptation of Algae to metal stress

Water environments are subject to local antropogenic impact (for instance heavy metal pollution) with repercussions on the algal component of the ecosystem. This leads to the development of various strategies/mechanisms of accumulation/detoxification of the metals (Cd, Zn, Pb. etc.) as adaptation responses of autotrophic mono- and multicellular organisms. Studies have been carried out in culture (at the morphological-functional, cellular, sub-cellular and biomolecular levels) on the ecophysiology, the ultastructure and the biochemistry of the acclimatisation (in the short term) and adaptation (in the long term) processes of macro- and micro-algae (red algae, blue algae and diatomeae in particular), in response to experimentally induced variations in the concentration of metals.

The adaptive responses of various species take place mainly:
  1. at morphological-ultrastructural level with the modulation of the wall and of the vescicolo- vacuolar system;
  2. at biosynthetic level with
These analyses have led to the identification of sensitive species (pollution bioindicators) and of species more or less resistant and/or tolerant to metal-induced "stress" (bio-accumulators) which can be used for the detoxification of the waters.

The following lines of basic research are currently active:
  1. Biology and Ecophysiology of marine algae
  2. Adaptation of sea and fresh water macro- and micro-algae to "stress" environmental factors: ecophysiology, ultrastructure and biochemistry
  3. Proteins and phycocolloids from macro-algae (COST 49).
The research is carried out in collaboration with Prof. G.Bressan, who oversees the taxonomic and ecological aspects and with Prof. G.Honsell of the University of Udine, whose speciality is in the field of Dinophyceae (red tides phenomenon).

Scientist in charge: L. Talarico.

Italiano - University TS - Biology - Research