Projects / Programmes
Natural hydrochemical background and dynamics of groundwater in Slovenia
| Code |
Science |
Field |
Subfield |
| 1.06.00 |
Natural sciences and mathematics |
Geology |
|
| Code |
Science |
Field |
| P470 |
Natural sciences and mathematics |
Hydrogeology, geographical and geological engineering |
groundwater, aquifer, chemistry, natural background, monitoring
Researchers (20)
Organisations (3)
Abstract
The aim of the project is to establish the natural hydrochemical backgrounds in groundwaters in Slovenia, as well as to determine the dynamics of aquifers and groundwater age. Known natural hydrochemical backgrounds are a basis for the estimation of the anthropogenic contamination of groundwater. In the framework of the project, natural backgrounds of relevant chemical parameters will be determined and factors will be identified, which determine the natural background of individual chemical parameters: chemical composition of host rocks, hydrogeological and hydrodynamic conditions, climate and vegetation cover in the aquifer recharge area. The age of groundwater will be determined using measurements of 3H activity analysis. Stable O and H isotopic composition of water will be determined, too.
All typical aquifer types occurring in Slovenia will be included into the investigation. Special attention will be paid to the sampling stations within the national groundwater monitoring network. The extended study will enable a detailed analysis of hydrogeological conditions and representativity of each sampling site.
In Slovenia – similar to many other European countries – nitrate represents a critical parameter deteriorating the quality status of groundwater. Therefore special attention will be devoted to this contaminant with respect to its natural background concentrations, as well as its leaching from soil and migration within the unsaturated zone of the aquifer.
Significance for science
By project implementation, plenty of new data on natural hydrochemical backgrounds in Slovenian groundwater was obtained. The results provided a very comprehensive picture of hydrochemical characteristics of groundwater in various aquifer types, and in different lithological, climatic, vegetational and other environmental conditions. A clarification of relations between chemical composition of water and environmental parameters is expected, representing a basis for the interpretation of groundwater chemical analyses.
Project results enable a quantitative interpretation of different processes and factors determining chemical and isotopic characteristics of groundwater. The main processes which were quantitatively evaluated within the project include the characteristics of carbonate chemical equilibrium in groundwater, the influence of soil CO2 on the carbonate equilibrium, mechanisms of groundwater pollution with nitrogen, the influence of silicate minerals on groundwater chemistry, and the altitude and continental isotope effect in groundwater. In the project, hydrochemical properties of microelements in groundwater were for the first time in Slovenia also systematically dealt with.
Project results also serve as a scientific base for upgrading conceptual models of groundwater bodies and aquifers. Hydraulic model design is not possible without reliable conceptual models providing a quantitative prognosis of various contaminants’ spreading in the groundwater. Up to present, the majority of the conceptual models available did not adequately take into consideration multiple hydrochemical and isotopic characteristics of the groundwater. The models also practically entirely lacked data on groundwater dynamics and age.
Previous investigations indicate agriculture as the most important diffuse source of nitrogen input into the soil and consequently of aquifer pollution load. Within this scope, models for the estimation of surplus nitrogen after its input into the soil have been developed and applied in our circumstances. These models are too rough and not accurate enough for measure-taking as well on the emission side (in the calculation of surplus nitrogen on soil level) as also regarding the imission (in the calculation of nitrate content in ground water). In project implementation a large quantity of measurement data was obtained, enabling a quantitative determination of impact of urban areas and agriculture on the increased nitrate concentrations in groundwater. Detailed knowledge of individual sampling points’ recharge areas can be used in the determination of correlations between land use characteristics, natural properties of recharge areas and hydrological properties of aquifers.
Significance for the country
The long-term effect of the project will be more efficient groundwater protection and an improved protection of natural resources in general. The importance of Slovenian drinking water resources is expected to increase in the future, especially in the light of the immanent climate change. A necessary goal at a national level is the preservation of good chemical status of water resources and imposing more rigorous standards of (ground)water protection. Reference data on the natural quality of groundwater will be used for the detection of possible negative quality trend developments, requiring immediate action.
Within the project, chemical properties of groundwater on the entire territory of Slovenia were determined. Up to the present, a comprehensive overview of groundwater chemistry for Slovenia has not been made. This data belongs to the basic information about Slovenia's natural characteristics and is thus widely useful, as well for further investigation work in this araea as also in the scope of economic exploitation of groundwater. The fact is that chemical characteristics of water significantly affect the usefulness of water in different technological processes; in this respect, mineralization (water hardness) and the degree of pollution, either with anthropogenic or also natural pollutants of groundwater, should be mentioned.
Project results are also a good basis for the implementation of the national monitoring of groundwater chemical status, performed by the Environment Agency of the Republic of Slovenia (ARSO), and for drinking water quality monitoring, implemented by the Ministry of Health. A prerequisite for adequate groundwater quality monitoring are appropriate sampling objects for the retrieval of representative groundwater samples from particular water-bearing strata, as well as a good knowledge and understanding of hydrogeological conditions in the aquifer, including hydrochemical processes determining the natural hydrochemical backgrounds. Project results are in this respect the basis for the determination of the representativity of individual monitoring objects by the MOP ARSO Monitoring Office, and in monitoring result interpretation. They enable a much more reliable estimation of the sources of particular chemical components (natural vs. anthropogenic). At the same time, the adequacy of individual monitoring objects will be evaluated with respect to their representativity. If necessary, the inadequate monitoring objects will be replaced.
Special significance of project results can also be seen in the area of planning protection measures for drinking water resources. Groundwater is the strongly prevailing drinking water resource for public supply in Slovenia, therefore its effective protection is a very important issue. The usual system of water resources protection are water protection areas. Because the chemistry of groundwater is highly linked with the geological, hydrogeological and geographical properties of aquifer recharge areas, project results will find direct applications also in the planning of water protection areas of individual water resources.
The project also provided very useful information for the preparation of the national Water Management Action Plan. Based on groundwater age and aquifer recharge rate, it is possible to estimate the time span necessary for the restoration measures to take effect. In highly dynamic aquifers a quick response to the restoration measures is expected, whereas in aquifers with a low throughput velocity, retaining older groundwater, the expected response time is much longer.
Nitrate contamination of groundwater is a pressing issue in Slovenia. Nitrates are the main concern in two out of three groundwater bodies with poor quality status. Special attention was thus paid to this pollutant with respect to its natural background concentrations, as well as anthropogenic inputs into groundwater.
Most important scientific results
Annual report
2008,
2009,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2008,
2009,
final report,
complete report on dLib.si
