Treatment of leachate from municipal landfills with elevated salinity

Project co-ordinator: Prof. Dr. Danijel Vrhovšek
LIMNOS

The sub-project in its first part will be closely connected to the WP 1.2. “Biological treatment of saline municipal wastewater” (salty communal waste waters), where the basic research of isolation of microbes tolerant toward higher concentrations and fast oscillations of salinity and the study of their metabolism will be performed. We will investigate which substrate, plant species, and microbes (filamentous fungi and yeasts) are the most appropriate for the treatment of leachate in conditions of elevated salinity. A knowledge of molecular mechanisms of halotolerance obtained on eukaryotic model micro-organisms is most easily applicable on (eukaryotic) plants, also those used in phytoremediation. The exploitation of genes identified in eukaryotic micro-organisms as the most important for halotolerance is one of the most interesting applied aspects, derived from the study of the osmoadaptive responses in fungi, and with the aim of generating strains and varieties of plants resistant to salt stress. Halotolerant plants would be useful both in phytoremediation and as agriculturally important crops for planting on salinised soil. Such investigations have been so far performed only on bacteria, phylogenetically less adequate as eukaryotic organisms.

The main goal of the project is to enhance the buffering capacity of the first part of the constructed wetland (CW), which is exposed to the highest oscillations in salinity and where the efficiency of the treatment in the lowest.

The research will be undertaken in several stages:

(1)Isolation of micro-organisms from the CW leachate established on the landfill site in Dragonja (coastal area).

(2)Research into the mechanisms of metabolism and growth of selected isolated micro-organisms.

(3)Tests on the existing CW in Dragonja, where we will optimise its performance by selection of the most appropriate substrate, plants, design of CW beds and water flow.

(4)Monitoring of CW performance by biotests.