Andres Marandi's Lab

Featured projects (1)

The aim of the project is to promote coordinated management and integrated protection of transboundary groundwater by creating a geoinformation platform (an integrated GIS modelling environment for the creation of digital hydrogeological maps and simulations of the quantity and quality of transboundary groundwater). As a part of the project, two cross-border clusters will be created, representing two geographical regions: Baltic and Eastern Europe. The project No.2018-1-0137 benefits from a € 2.447.761 grant Iceland, Liechtenstein and Norway through the EEA and Norway Grants Fund for Regional Cooperation. Duration: 1 September 2020 - 31 Dec 2023 Project homepage: [under development] Partnerships: (1) Polish Geological Institute - National Research Institute (lead partner) (2) State Enterprise "Ukrainian Geological Company" (3) Geological Survey of Estonia (4) DC of NJSC "NADRA UKRAJYNY" "Zahidukrgeologiya" (UA) (5) Intergraph Polska Sp. z o.o. (PL) (6) University of Latvia, Faculty of Geography and Earth Sciences (7) The Institute of Geology and Geochemistry of Combustible Minerals of National Academy of Sciences of Ukraine (8) Latvian Environment, Geology and Meteorology Centre (9) Geological Survey of Norway

Featured research (5)

The aim of the document is to create a conceptual understanding of the hydrogeological processes and flow dynamics across the national borders in two different pilot territories - Polish-Ukrainian and Latvian-Estonian border area. Within the framework of this report, assessment of transboundary groundwater resources, as well as the determination of groundwater flow volumes across the state borders has been carried out. The report has been developed by seven project partners: Polish Geological Institute - National Research Institute, Latvian Environment, Geology and Meteorology Centre, University of Latvia, State Enterprise "Ukrainian Geological Company", Geological Survey of Estonia, The Institute of Geology and Geochemistry of Combustible Minerals of National Academy of Sciences of Ukraine and DC of NJSC "NADRA UKRAJYNY" "Zahidukrgeologiya".
Joint methodology for identification and assessment of GDTEs was developed to identify GDTEs in trans-boundary Gauja-Koiva river basin (funded by Interreg EstLat project “GroundEco”). The methodology and best GDTEs assessment techniques were tested in two pilot areas – Matsi spring fen in Estonia and Kazu leja valley in Latvia. Finally, recommendations for better GDTEs monitoring and future works were developed. All results will be used to support the development of 3rd cycle River Basin management Plans (2021–2027) for Estonia and Latvia. We hope that this report will be useful for many habitat and hydro(geo)experts working with assessment of GDTEs inline with European Water Framework Directive as well as serves as a good starting point for better understanding of GDTEs functioning and linkage with groundwater resources.
This research is carried out in the framework of the project "Joint management of groundwater dependent ecosystems in transboundary Gauja-Koiva river basin" (GroundEco, Est-Lat62) funded by ERDF Interreg Estonia-Latvia cooperation programme. The main aim of GroundEco is to develop a common understanding and joint methodology for the Estonian and Latvian environmental authorities in the identification and assessment of groundwater dependent terrestrial ecosystems. Special emphasis is placed on the development and use of conceptual models. The Matsi spring fen was chosen as the pilot study area in the Estonian part of the transboundary Gauja-Koiva river basin. It is located in SE Estonia, Võru county, Rõuge parish, Matsi village. The spring fen has been previously inventoried as an important groundwater dependent terrestrial ecosystem with a very representative botanical community belonging to the Fennoscandian mineral-rich springs and spring fens (code 7160) Habitats Directive Annex I habitat type. The spring fen (elevation 66 m asl) is situated in a sapping valley in the left brim of the Mustjõgi valley. The Mustjõgi valley cuts through a sandstone plateau (elevation 89 m asl) of Middle-Devonian Givetian Stage (Gauja Fm.). It has been hypothesized that the spring fen is dependent on the Middle-Devonian groundwater body in the Gauja-Koiva River Basin, composed of Middle-Devonian Gauja (D2gj) and the overlying aquifers/aquitards of the Quaternary (Q) system. In order to verify the spring fen's dependence on the groundwater body, a comprehensive hydrogeological study was carried out involving hydrodynamic and hydrochemical monitoring. A GPR survey combined with shallow sediment coring revealed that the mean thickness of peat was 1.6±0.7 m. A tufa layer with a mean thickness of 0.6±0.4 m, underlies the peat. A monitoring network of 22 points, including 11 shallow piezometers, 3 dug wells in the shallow Q aquifer, 2 borewells in D2gj aquifer, 3 springs and 3 streams, was set up. In the core of the spring fen, two piezometer nests were constructed (screen depth in peat <1.5 m and >1.5 m in below peat stratum). Twelve monitoring points were equipped with water level, temperature and three electrical conductivity data loggers. The monitoring program was to be carried out in the period of April 2019-April 2020. As of January 2020, five sampling campaigns have been carried out and 76 water samples have been collected. In total 65 physico-chemical parameters were determined in each case either in-situ or in the laboratories of Tallinn University (major ions and macronutrients) and Latvian University (trace metals and stable isotopes). In natural conditions the hydraulic heads in the peat and below peat stratum in the fen core fluctuated within 10 cm during the monitoring period. In below peat stratum, the hydraulic heads were constantly above the ground surface. The observed barometric efficiency in the adjacent borewell (10846) screening the D2gj aquifer indicated its confinement. The water table in the fen was controlled by the beaver dam at the outflow. The outflow discharge was evenly 12.8±1 l/s throughout the monitoring period, which in turn refers to the constant pressure exerted by the outcropping confined aquifer. The influence of meteoric recharge on the head variation was more pronounced in the fen edge piezometers, indicating to the probable partial contribution from the Q aquifers capping the surrounding plateau. The dominating impact of the D2gj aquifer to the spring fen, inferred from the
The study focuses on chemical composition of stream and subsurface water in the catchments of two small arctic alpine lakes in the Kilpisjärvi area (northwest Finland). Differences and changes in chemical components of both water types are followed in order to detect spatial variability and impact of environmental factors. To achieve this, ion compositions of subsurface water and streams were measured at 12 sites in the catchments of Lakes Saana and Saanalampi during four years (2008-2010, and again in 2017). In the Lake Saanalampi catchment, the salinity of stream water (7.0 to 12.7 µS·cm −1) corresponded to that of snow. In the catchment of Lake Saana, however, the conductivity in stream water was much higher (40 to 220 µS·cm −1), connected mainly to the increase of SO 4 2− and less with Mg 2+ and Ca 2+ contents, especially in the western part of the Saana catchment. These results demonstrate that arctic conditions do not preclude intense chemical weathering where conditions are favourable. Although chemical composition of the soil fluid does not match the geochemical signal from the local soil, rock composition, especially the presence of pyrite, is the main controller of chemical weathering rates of the rocks on the area. This supports earlier views that the character of precipitation mostly controls water chemistry of local lakes in the Kilpisjärvi area.
The ‘Gibbs Diagram’ represents some of the key processes controlling surface water chemistry. This review highlights that the processes listed on the Gibbs Diagram may not be applicable for assessing processes controlling groundwater chemistry. We discuss the importance of geochemical processes governing groundwater chemistry in the Gibbs Diagram framework. We show that the processes represented on the Gibbs Diagram—originally developed for surface waters—unlikely represent key processes controlling the chemistry of most groundwater systems. Available via Sci-Hub:

Lab head

Andres Marandi
  • Hydrogeology and Environmental Geology
About Andres Marandi
  • My current interest in the field of hydrogeology includes research groundwater resources, especially the coupling of hydrodynamic and geochemical modelling for these purposes. Special interest is paid on changes to water budget generated by large intakes e.g. underground mines.

Members (5)

Valle Raidla
  • Geological Survey of Estonia
Siim Tarros
  • Geological Survey of Estonia
Joonas Pärn
  • Geological Survey of Estonia
Maile Polikarpus
  • Geological Survey of Estonia
Magdaleena Männik
  • Geological Survey of Estonia