Slovenian karst areas extend over 43% of the country; limestones and dolomites of the Mesozoic er... more Slovenian karst areas extend over 43% of the country; limestones and dolomites of the Mesozoic era prevail. In Slovenia karst groundwater contributes up to 50% of the total drinking water supply. The quality of water is very high, despite the fact that it is extremely vulnerable to pollution. The present article is a study and a review of the potential and actual sources of pollution to the groundwater in the selected karst aquifers (the Kras, Velika planina and Snežnik plateaus), which differ in their natural characteristics. Unlike the other selected plateaus, the Kras plateau is inhabited. There are several settlements in the area and the industrial, agricultural and traffic activities carried out that represent a serious threat to the quality of karst groundwater. The Velika planina and Snežnik plateaus do not have permanent residents, however there are some serious hazards to the quality of the karst springs arising from sports, tourist, construction and farming activities, as well as from the traffic related to them. Despite relatively favourable conditions for protection, many important karst aquifers and springs are improperly protected in Slovenia. The reason is the lack of knowledge about sustainable water management in karst regions and the confusion in drinking water protection policy.
That flattener is a cave passage, which though wide, is so low that movement is only possible in ... more That flattener is a cave passage, which though wide, is so low that movement is only possible in a prone position [10]. see also crawl.? ... KarstBase a bibliography database in karst and cave science. ... That donga is in the nullarbor plain, australia, a shallow, closed depression, ...
Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in S... more Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in Slovenia during 26 high-flow events in an 18-month monitoring period. A conceptual model explaining this anomalous SEC variability is presented and reproduced by numerical modelling, and the practical relevance for source protection zoning is discussed. After storm rainfall, discharge increases rapidly, which is typical for karst springs. SEC displays a first maximum during the rising limb of the spring hydrograph, followed by a minimum indicating the arrival of freshly infiltrated water, often confirmed by increased levels of total organic carbon (TOC). The anomalous behaviour starts after this SEC minimum, when SEC rises again and remains elevated during the entire high-flow period, typically 20-40 µS/cm above the baseflow value. This is explained by variable catchment boundaries: When the water level in the aquifer rises, the catchment expands, incorporating zones of groundwater with higher SEC, caused by higher unsaturated zone thickness and subtle lithologic changes. This conceptual model has been checked by numerical investigations. A generalized finite-difference model including high-conductivity cells representing the conduit network ("discrete-continuum approach") was set up to simulate the observed behaviour of the karst system. The model reproduces the shifting groundwater divide and the nearly simultaneous increase of discharge and SEC during high-flow periods. The observed behaviour is relevant for groundwater source protection zoning, which requires reliable delineation of catchment areas. Anomalous behaviour of SEC can point to variable catchment boundaries that can be checked by tracer tests during different hydrologic conditions.
Four methods of groundwater vulnerability mapping have been applied in a Slovene karst catchment ... more Four methods of groundwater vulnerability mapping have been applied in a Slovene karst catchment and validated by tracer tests. The test site is characterised by high water table fluctuations, manifested in intermittent lakes and variable drainage divides. A first multi-tracer test (two injections) allowed subdivision of the catchment into zones of different degrees of contribution ('inner zone' and 'outer zone'). For vulnerability mapping, only methods that consider the specific nature of karst aquifers such as heterogeneity and duality of infiltration processes, were selected: EPIK, PI, the 'Simplified Method' and the 'Slovene Approach'. For validation, a second multi-tracer test (four injections) was carried out. The time of first detection and the normalised recovery were used as validation criteria. The results suggest that EPIK and the Simplified Method sometimes overestimate vulnerability, while PI and the Slovene Approach tend to deliver more realistic results, at least during low-flow conditions. The Slovene Approach gives the clearest guidance on how to deal with hydrologic variability, for example by assigning lower vulnerability to occasionally active sinking surface waters than to permanent ones. As a conclusion, commonly accepted validation techniques are needed and should be applied by default to evaluate different vulnerability mapping methods and the resulting maps.
The vulnerability of four European aquifers with different hydrogeological and climatic character... more The vulnerability of four European aquifers with different hydrogeological and climatic characteristics was evaluated using the COP method. The results obtained were statistically analyzed by determination coefficients to measure which factor has greater importance in the vulnerability index. Furthermore, a new parameter has been designed to measure the vulnerability for the whole of the aquifer. The results demonstrate that COP is a useful method to assess the vulnerability of the test sites under consideration. The results obtained are coherent with the conceptual model of each pilot aquifer and the available hydrogeological information (hydrographs, isotopic data, tracer tests). Fissured carbonate aquifers (diffuse flow systems) are less vulnerable than karst aquifers (conduit flow systems) and the vulnerability index is more positively correlated with the O factor (unsaturated zone protection capacity) in the first case. The karst aquifers are more vulnerable than fissured aquifers and they show a higher correlation between the C factor (karst features) and the vulnerability index. Climatic variation (precipitation for example) influences the final vulnerability index of the aquifers according to the weight in the index and the spatial distribution.
In Kunming area (6.8 mio population) two big interventions are in progress: construction of a new... more In Kunming area (6.8 mio population) two big interventions are in progress: construction of a new airport, whose 23 km2 will extend across karst terrain northeast of the city, and extensive uptake of water from karst aquifers for drinking and agricultural use. In the study an interdisciplinary approach was utilized to demonstrate the need for holistic karstology studies prior to performing extensive interferences in karst environment. This study included survey of surface karst features and microscopic analyses of rock samples in the area of the new airport location, accompanied with hydrogeological studies and microbiological analyses of two karst drinking water sources in its vicinity (Qinglongdong, Huanglongdong). Results showed the specific characteristics of the subsoil stone forest that indicated a high level of karstification. The groundwater flow direction and velocity from the sinking Qiaotou stream at the margin of the new airport area toward the Huanglongdong spring was proved with a single tracer test. Individual measurements of selected chemical and bacteriological parameters were carried out and showed substantial pollution of both springs due to various types of human activities in the catchments. Spring water contained several dozen to several hundreds of viable heterotrophic and coliform bacteria in one milliliter and showed increased values of nitrates and ophosphates. Huanglongdong spring additionally showed increased values of chlorides and sulfates. The results of the study pointed to the necessity of taking immediate measures for the springs' protection and show the importance of interdisciplinary research when planning anthropogenic activities in karst. Expert in karst geomorfology and hydrology, involved in karst research in China
The comprehensive knowledge of karst surface, caves, waters and biodiversity were examined with s... more The comprehensive knowledge of karst surface, caves, waters and biodiversity were examined with special emphasis on planning for environmental management and land use in karst regions using examples of projects performed by the staff from the Karst Research Institute ZRC SAZU. Based on the knowledge of karst, karst phenomena, karst waters and karst biodiversity, karstological monitoring was developed throughout the construction of expressways and planning for railways on karst terrain. Newly revealed karst phenomena were properly preserved. Regular climatic and biological monitoring were developed and implemented, as well as karstology consultation with an emphasis on the impact of the use of caves as natural assets. To understand karst, its evolution dynamics and processes, models were developed with which the study of the risk posed by dam site construction in karst areas was possible. Karst aquifers and their protection were studied using tracer tests and different methods of the transfer of contaminants through the vadose zone and underground flow connections. In assessing the vulnerability and contamination risk of groundwater, a comprehensive method was elaborated. Microorganisms and fauna of dripping water in caves were used as monitors of cave ecosystem health. By applying high-quality karstological research results from individual spheres of karstology and interdisciplinary studies, a foundation for sustainable planning of life in karst regions that will consider the natural and cultural characteristics and vulnerability of karst landscapes has been established.
EGU General Assembly 2009, held 19- …, Jan 1, 2009
Abstract An overview of exceptional natural processes or natural hazards from the human perspecti... more Abstract An overview of exceptional natural processes or natural hazards from the human perspective in Slovene karst areas is made. Some types of natural hazards are typical for karst due to the process of karstification and resulting geomorphological and hydrological ...
J. Mudry et al. (eds.), H2Karst Research in Limestone Hydrogeology, Environmental Earth Sciences,
Abstract In a shallow karst aquifer in SW Slovenia assessment of groundwater and drinking water s... more Abstract In a shallow karst aquifer in SW Slovenia assessment of groundwater and drinking water source vulnerability has been performed using different methods. The small, but well defined, Orehek karst is mainly drained by the no longer exploited orentan spring. The recharge area of the spring is well karstified, densely wooded, and covered by thin soils. Besides precipitation, the pring is additionally recharged by temporally active sinking streams. To assess the vulnerability, two methods, COP+K and Slovene approach, have been applied. Both methods provide tools for assessing vulnerability in carbonate rocks. They both ank among very sophisticated methods that require vast amounts of data, time, and financial and technical resources. Both ethods share the same methodological procedure and consider the same type of information, categorized by the same factors. On the other hand, the scoring, classification and weighting of individual arameters between the methods are different. Consequently, the resulting maps differ significantly. Major differences between the results are identified and discussed.
Slovenian karst areas extend over 43% of the country; limestones and dolomites of the Mesozoic er... more Slovenian karst areas extend over 43% of the country; limestones and dolomites of the Mesozoic era prevail. In Slovenia karst groundwater contributes up to 50% of the total drinking water supply. The quality of water is very high, despite the fact that it is extremely vulnerable to pollution. The present article is a study and a review of the potential and actual sources of pollution to the groundwater in the selected karst aquifers (the Kras, Velika planina and Snežnik plateaus), which differ in their natural characteristics. Unlike the other selected plateaus, the Kras plateau is inhabited. There are several settlements in the area and the industrial, agricultural and traffic activities carried out that represent a serious threat to the quality of karst groundwater. The Velika planina and Snežnik plateaus do not have permanent residents, however there are some serious hazards to the quality of the karst springs arising from sports, tourist, construction and farming activities, as well as from the traffic related to them. Despite relatively favourable conditions for protection, many important karst aquifers and springs are improperly protected in Slovenia. The reason is the lack of knowledge about sustainable water management in karst regions and the confusion in drinking water protection policy.
That flattener is a cave passage, which though wide, is so low that movement is only possible in ... more That flattener is a cave passage, which though wide, is so low that movement is only possible in a prone position [10]. see also crawl.? ... KarstBase a bibliography database in karst and cave science. ... That donga is in the nullarbor plain, australia, a shallow, closed depression, ...
Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in S... more Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in Slovenia during 26 high-flow events in an 18-month monitoring period. A conceptual model explaining this anomalous SEC variability is presented and reproduced by numerical modelling, and the practical relevance for source protection zoning is discussed. After storm rainfall, discharge increases rapidly, which is typical for karst springs. SEC displays a first maximum during the rising limb of the spring hydrograph, followed by a minimum indicating the arrival of freshly infiltrated water, often confirmed by increased levels of total organic carbon (TOC). The anomalous behaviour starts after this SEC minimum, when SEC rises again and remains elevated during the entire high-flow period, typically 20-40 µS/cm above the baseflow value. This is explained by variable catchment boundaries: When the water level in the aquifer rises, the catchment expands, incorporating zones of groundwater with higher SEC, caused by higher unsaturated zone thickness and subtle lithologic changes. This conceptual model has been checked by numerical investigations. A generalized finite-difference model including high-conductivity cells representing the conduit network ("discrete-continuum approach") was set up to simulate the observed behaviour of the karst system. The model reproduces the shifting groundwater divide and the nearly simultaneous increase of discharge and SEC during high-flow periods. The observed behaviour is relevant for groundwater source protection zoning, which requires reliable delineation of catchment areas. Anomalous behaviour of SEC can point to variable catchment boundaries that can be checked by tracer tests during different hydrologic conditions.
Four methods of groundwater vulnerability mapping have been applied in a Slovene karst catchment ... more Four methods of groundwater vulnerability mapping have been applied in a Slovene karst catchment and validated by tracer tests. The test site is characterised by high water table fluctuations, manifested in intermittent lakes and variable drainage divides. A first multi-tracer test (two injections) allowed subdivision of the catchment into zones of different degrees of contribution ('inner zone' and 'outer zone'). For vulnerability mapping, only methods that consider the specific nature of karst aquifers such as heterogeneity and duality of infiltration processes, were selected: EPIK, PI, the 'Simplified Method' and the 'Slovene Approach'. For validation, a second multi-tracer test (four injections) was carried out. The time of first detection and the normalised recovery were used as validation criteria. The results suggest that EPIK and the Simplified Method sometimes overestimate vulnerability, while PI and the Slovene Approach tend to deliver more realistic results, at least during low-flow conditions. The Slovene Approach gives the clearest guidance on how to deal with hydrologic variability, for example by assigning lower vulnerability to occasionally active sinking surface waters than to permanent ones. As a conclusion, commonly accepted validation techniques are needed and should be applied by default to evaluate different vulnerability mapping methods and the resulting maps.
The vulnerability of four European aquifers with different hydrogeological and climatic character... more The vulnerability of four European aquifers with different hydrogeological and climatic characteristics was evaluated using the COP method. The results obtained were statistically analyzed by determination coefficients to measure which factor has greater importance in the vulnerability index. Furthermore, a new parameter has been designed to measure the vulnerability for the whole of the aquifer. The results demonstrate that COP is a useful method to assess the vulnerability of the test sites under consideration. The results obtained are coherent with the conceptual model of each pilot aquifer and the available hydrogeological information (hydrographs, isotopic data, tracer tests). Fissured carbonate aquifers (diffuse flow systems) are less vulnerable than karst aquifers (conduit flow systems) and the vulnerability index is more positively correlated with the O factor (unsaturated zone protection capacity) in the first case. The karst aquifers are more vulnerable than fissured aquifers and they show a higher correlation between the C factor (karst features) and the vulnerability index. Climatic variation (precipitation for example) influences the final vulnerability index of the aquifers according to the weight in the index and the spatial distribution.
In Kunming area (6.8 mio population) two big interventions are in progress: construction of a new... more In Kunming area (6.8 mio population) two big interventions are in progress: construction of a new airport, whose 23 km2 will extend across karst terrain northeast of the city, and extensive uptake of water from karst aquifers for drinking and agricultural use. In the study an interdisciplinary approach was utilized to demonstrate the need for holistic karstology studies prior to performing extensive interferences in karst environment. This study included survey of surface karst features and microscopic analyses of rock samples in the area of the new airport location, accompanied with hydrogeological studies and microbiological analyses of two karst drinking water sources in its vicinity (Qinglongdong, Huanglongdong). Results showed the specific characteristics of the subsoil stone forest that indicated a high level of karstification. The groundwater flow direction and velocity from the sinking Qiaotou stream at the margin of the new airport area toward the Huanglongdong spring was proved with a single tracer test. Individual measurements of selected chemical and bacteriological parameters were carried out and showed substantial pollution of both springs due to various types of human activities in the catchments. Spring water contained several dozen to several hundreds of viable heterotrophic and coliform bacteria in one milliliter and showed increased values of nitrates and ophosphates. Huanglongdong spring additionally showed increased values of chlorides and sulfates. The results of the study pointed to the necessity of taking immediate measures for the springs' protection and show the importance of interdisciplinary research when planning anthropogenic activities in karst. Expert in karst geomorfology and hydrology, involved in karst research in China
The comprehensive knowledge of karst surface, caves, waters and biodiversity were examined with s... more The comprehensive knowledge of karst surface, caves, waters and biodiversity were examined with special emphasis on planning for environmental management and land use in karst regions using examples of projects performed by the staff from the Karst Research Institute ZRC SAZU. Based on the knowledge of karst, karst phenomena, karst waters and karst biodiversity, karstological monitoring was developed throughout the construction of expressways and planning for railways on karst terrain. Newly revealed karst phenomena were properly preserved. Regular climatic and biological monitoring were developed and implemented, as well as karstology consultation with an emphasis on the impact of the use of caves as natural assets. To understand karst, its evolution dynamics and processes, models were developed with which the study of the risk posed by dam site construction in karst areas was possible. Karst aquifers and their protection were studied using tracer tests and different methods of the transfer of contaminants through the vadose zone and underground flow connections. In assessing the vulnerability and contamination risk of groundwater, a comprehensive method was elaborated. Microorganisms and fauna of dripping water in caves were used as monitors of cave ecosystem health. By applying high-quality karstological research results from individual spheres of karstology and interdisciplinary studies, a foundation for sustainable planning of life in karst regions that will consider the natural and cultural characteristics and vulnerability of karst landscapes has been established.
EGU General Assembly 2009, held 19- …, Jan 1, 2009
Abstract An overview of exceptional natural processes or natural hazards from the human perspecti... more Abstract An overview of exceptional natural processes or natural hazards from the human perspective in Slovene karst areas is made. Some types of natural hazards are typical for karst due to the process of karstification and resulting geomorphological and hydrological ...
J. Mudry et al. (eds.), H2Karst Research in Limestone Hydrogeology, Environmental Earth Sciences,
Abstract In a shallow karst aquifer in SW Slovenia assessment of groundwater and drinking water s... more Abstract In a shallow karst aquifer in SW Slovenia assessment of groundwater and drinking water source vulnerability has been performed using different methods. The small, but well defined, Orehek karst is mainly drained by the no longer exploited orentan spring. The recharge area of the spring is well karstified, densely wooded, and covered by thin soils. Besides precipitation, the pring is additionally recharged by temporally active sinking streams. To assess the vulnerability, two methods, COP+K and Slovene approach, have been applied. Both methods provide tools for assessing vulnerability in carbonate rocks. They both ank among very sophisticated methods that require vast amounts of data, time, and financial and technical resources. Both ethods share the same methodological procedure and consider the same type of information, categorized by the same factors. On the other hand, the scoring, classification and weighting of individual arameters between the methods are different. Consequently, the resulting maps differ significantly. Major differences between the results are identified and discussed.
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