Evapotranspirative willow systems (ETS) with zero discharge were developed in Denmark in collaboration with scientists from Aarhus University. The lecture was given to master students and interested researchers at the department of Biological Sciences. The basic design parameters for ETS were presented along with reference evapotranspiration and parameters increasing the actual evapotranspiration. The lecture included a detailed presentation of the novel design of an experimental ETS in Slovenia with its structural modifications and experiment set-up. The experimental ETS in Slovenia included a drainage system installed at the surface of test beds in order to divert away the rainwater. The surface of the ETS bed was inclined to divert the surplus rainwater to a collection pipe at the lowest point of the surface. Besides this, a clay layer, 10 cm beneath the bed surface was established to reduce the infiltration of rainwater to the deeper parts of the beds. The nine test beds of the pilot ETS were equipped with probes to measure soil water content in order to better determinate the evapotranspiration. The lecture also presented the greenhouse experiment where salinity effects on willow growth were investigated. The tested concentrations of 0.1, 0.2, 0.5 and 1 g/L did not inhibit transpiration of willow seedlings during the first vegetation season.
B.04 Guest lecture
COBISS.SI-ID: 5590379Collected but untreated (or poorly treated) wastewater (WW) has been recognized as a key problem among the threats to water quality in the Danube region. Therefore, Joint Research Centre (JRC) has involved expertise in the Danube region to gather knowledge and know-how about possible alternatives for wastewater (WW) treatment. The overall aim of this project was to identify an affordable and sustainable solution for the WW treatment of small and medium settlements. In the present work three settlements (500-2000 PE) of Kamniška Bistrica Catchment were selected as case studies. In this frame, decentralized approaches were compared to the option of collecting all WW in a centralized treatment plant. Several technologies were assessed considering the most recent systems to be applied in small settlements. First, the technical alternatives were screened. The technical options were derived in three groups: i) technological options (SBR, MBR); ii) nature-based solutions (different types of constructed wetlands) and iii) resource-oriented options (evapotranspirative willow systems and algae-based technology). Second, a selection of the preferred alternative was done through socioeconomic analysis and multicriteria analysis; and third, technical and financial apprisal of the selected alternative was elaborated. The results showed that a decentralized approach offers real advantages – economic, social and environmental – only if very robust and low-maintenance technologies are used. Nature-based solution were proposed, namely constructed wetlands (CW), a technology in use at market scale for 50 years. The key aspect to guarantee effectiveness of CW is a proper, scientific based design, for which a very wide scientific literature is available on the issue, together with several guidelines and manuals.
D.06 Final report on a foreign/international project
COBISS.SI-ID: 5396843Evapotranspiration willow systems (ETS) are green technology for treatment and reuse of wastewater, where all of the wastewater is used for plants growth. It is expected that due to no discharge over time salt concentration in ETS increases which impacts the growth of willows and efficiency of the system. The impact of different salt concentrations on the growth and evapotranspiration of three willow clones were examined in a pot experiment. Native clone of white willow (Salix alba, ‘V 160’) and two of its hybrids (‘V 093’ and ‘V 052’) were tested at four concentrations of salt, namely 0.1; 0.2; 0.5 and 1 g/L. The amount of added water and water consumption were measured on a daily basis. From the absolute water use a normalized relative transpiration (NRT) was calculated. At the end of the experiment the aboveground produced biomass was measured. The results showed no negative impact of tested salt concentration on transpiration and willow growth. Clone ‘V 160’ had higher evapotranspiration and biomass production compared to ‘V 093’ and ‘V 052’ at all salt concentrations. Literature reports that tested salt concentrations reduce transpiration of willow cutting in a laboratory hydroponic setting; however, this experiment showed that salt concentrations should be much higher to cause effect to willows growing in soil.
D.10 Educational activities
COBISS.SI-ID: 5344363The manual is intended for managers and operators of utility services and represents the transfer of knowledge into practice. The manual gives detailed instructions for the operation and maintenance of nature-based solutions, with an emphasis on constructed wetlands. Such systems are easy to operate and maintain, however, regular monitoring of operation and certain maintenance measures are required. The manual presents the main technical characteristics of various treatment systems, followed by a description of the operation of each component (pumping stations, inflow and outflow pipes, plants, substrate) and action in case of problems. For each system, the system start-up process is described and a maintenance table with a timeline of implementation is given. Instructions for visual inspection of the system, including the outflow and the expected efficiency of operation, are given. A questionnaire / technical sheet for maintenance workers was created, which can be used on the field at the time of system inspection.
F.17 Transfer of existing technologies, know-how, methods and procedures into practice
COBISS.SI-ID: 5397355An expert article represents green technologies and their use in Slovenia in a popular manner. It is one of the few publications about such systems in Slovene. Through the imitation of natural processes and systems green technologies enable the reduction of the environmental footprint of human society, greater adaptability to climate change, sustainable management of natural resources and raising the quality of the living environment. The paper presents a multipurpose water retention reservoir in Podutik, Ljubljana, an evapotranspiration willow system in Ajdovščina, a separation sanitary unit in Sečovlje, a phytoremediation of contaminated soils in Šmartno pri Litiji, a treatment plant with algal bacterial biomass at a biogas plant in Ljubljana, and aquaponic systems in Ajdovščina and Naklo. All systems have been established within different research projects, with which we obtained important scientific results regarding the effectiveness of systems performance, the fate of pollutants and the possibility of reusing resources. In addition to scientific findings, pilot devices also contribute significantly to raising awareness about green technologies, knowledge of individual systems and awareness of the importance of reuse of resources.
F.17 Transfer of existing technologies, know-how, methods and procedures into practice
COBISS.SI-ID: 4969835