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Community news

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That equivalent per million is the number of equivalent weights in a million parts per weight solution [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for substances (Keyword) returned 33 results for the whole karstbase:
Showing 16 to 30 of 33
Agriculture and nature conservation in the Moravian karst (Czech Republic), 1999,
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Balk Ivan, Bosk Pavel, Jano Jozef, Stefka Leos
Moravian Karst is a narrow strip of limestone with long history of settlement, agricultural use and man impact to karst. It is naturally divided into smaller units; karst plateaus; separated by deep valleys (glens). Each plateau has different proportion of land use, i.e. the percentage of agricultural land, forests, etc. The agricultural land constitutes now up to 70% in the north and max. 30% in the centre and south of the total area of plateaus. Intensive agricultural use of the arable land since 60ties of this Century caused great impact to quality of soils and groundwater by overdoses of fertilisers and other artificial chemical substances. Detailed research in 1980 to 1997 resulted in a plan of care based on the zonation of land. There were defined zones with different degree of restriction of land use, agricultural activities and application of fertilisers and biocides. Arable lands has been gradually changed to meadows and pastures by introduction of grass since 1987 in the most strictly protected zone to protect especially subsurface karst forms.

Ecological incidents in Northern Adriatic Karst (Croatia), 2000,
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Geres D, Rubinic J, Ozanic N,
In spite of growing efforts to preserve the quality of groundwater resources, accidental pollution is becoming increasingly frequent, resulting in long-lasting impact on the groundwater status. The consequences of ecological accidents are particularly expressed in karst regions, which are caused by the geological properties of the area where the groundwater aquifers are situated, as well as by hydrological circumstances which also influence the dynamic mechanisms of water flow and transportation of pollution in the karst environment. The paper stresses the hydrological component of karst aquifer function and the related role of hydrology in assessment of the hazards caused by accidental pollution and, once the accident has happened, in monitoring the situation and forecasting the possible impact on water resources. The analysis of ecological accidents in the karst has been made, based on the actual examples of accidents involving fuel substances recorded in the Northern Adriatic karst area in Croatia in the period from 1990 to 1998. The basic characteristics of the mechanism of water movement in the karst are presented from the hydrological standpoint, as well as the related risk of rapid transportation of pollutants into the parts of the aquifers used for water supply. The paper also contains proposals for possible approaches to protection of particularly valuable water resources in the karat from accidental pollution occurring in road transport

Raw sewage and solid waste dumps in lava tube caves of Hawaii Island, 2003,
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Halliday, W. R.
Lava tubes on the island of Hawaii (and elsewhere) are possible subsurface point sources of contamination in addition to more readily identifiable sources on the surface. Human and animal waste, and hazardous and toxic substances dumped into lava tube caves are subject to rapid transport during flood events, which are the dominant type of groundwater flow through Hawaiian lava tubes. Although these waste materials may not be a major source of pollution when compared with some surface sources, this potential hazard should be evaluated much as in the case of karstic floodwater conduits.

Surface and subsurface environmental degradation in the karst of Apulia (southern Italy), 2003,
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Parise M. , Pascali V. ,
Karst environments are highly vulnerable to a variety of degradation and pollution problems. Geology (fractured carbonate rocks), morphology (presence of a network of cavities produced by karst processes), and hydrogeology (rapid concentrated flow through fractures and conduits) of karst carbonates strongly favour the movement of contaminants towards the water table. In particular, poor quality of subsurface water can derive from polluting substances flowing at the surface, and/or by direct immission of liquid and solid waste into the water table through the systems of conduits and joints in the rock mass. As a consequence, water quality can deteriorate severely, which implies very high economic and social costs in order to clean the polluted sites and restore the original situation. In some cases, such as when the original karst morphology is changed because of anthropogenic interventions, the variations created in the landscape are not recoverable, and a loss of sites of naturalistic interest has to be registered. High vulnerability of a typical karst region of the Mediterranean area is illustrated in this paper by describing some case studies from Apulia, southern Italy. The Apulia region, where karst processes have had a prominent role in the development of the present landscape, is mostly underlain by intensely karstified limestone. Two cases of pollution due to solid waste into karst cavities (Grave di S. Leonardo in the Gargano Promontory and Grave Pelosello in the Murge plateau), landscape transformation in the Minervino Murge area, and degradation of Gravina Monsignore, a typical karst valley in southeastern Murge, are described in the paper. In two out of four cases, degradation of the sites was discovered thanks to activity from local speleologists, who also acted as promoters for cleaning and safeguarding the polluted sites. These examples underline well the mismanagement of karst territories (in particular, the common practice to dump refuse into sinkholes and caves), the pollution of limestone aquifers, and the effects that such pollution in karst areas might have in terms of the risk to public health

Dissolved organic carbon in precipitation, throughfall, stemflow, soil solution, and stream water at the Guandaushi subtropical forest in Taiwan, 2003,
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Liu C. P. , Sheu B. H. ,
The concentration and flux of dissolved organic carbon (DOC) were measured in precipitation, throughfall, stemflow, soil solution, and stream water for three types of subtropical forest stands, a Chinese fir (Cunninghamia lanceolata) plantation, a secondary hardwood, and a natural hardwood stand in Guandaushi forest in central Taiwan from January 1998 to December 1998. The mean DOC concentration in precipitation was 4.7 mg l(-1). However, in the rain passing through the tree canopies and barks as throughfall and stemflow, the mean concentrations were 7.0 and 30.8, 9.9 and 10.0, and 8.3 and 7.2 mg l(-1) in the Chinese fir plantation, the secondary hardwood, and the natural hardwood, respectively. Mean DOC concentrations in soil solution were lower in the Chinese fir plantation than both hardwoods, and decreased with depth of soil profiles. Stemflow DOC flux (132.4 kg ha(-1)) in the Chinese fir plantation was much higher than the other hardwood stands (15.3 and 6.7 kg ha(-1) in secondary and natural hardwood, respectively). The monthly variations of DOC concentrations were very similar in throughfall and stemflow at the three stands, showing an increase in the beginning of the growing season in April. No clear monthly variations in soil solution DOC concentrations (mean from 3.2 to 21.3 mg l(-1) in different stands and for different depths) were found in our study. DOC concentrations (mean 2.7 mg l(-1)) in the stream draining the watershed were higher in spring and in winter. (C) 2002 Elsevier Science B.V. All rights reserved

Study of soil leachates in doline above the Beke Cave, Hungary, 2004,
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Tatar E. , Mihucz V. G. , Tompa K. , Poppl L. , Zaray G. , Zambo L. ,
Fulvic acid, Ca and Mg concentrations as well as dissolved inorganic carbon (DIC), pH and electric conductivity values of soil solutions which resulted from injecting bidistilled water onto glass columns filled with different soils (black rendzina, brown rendzina, red clayey rendzina, red clay) characteristic of the Aggtelek karst system (NE Hungary), were determined. Identification and determination of fulvic acid were achieved by size exclusion chromatography (SEC) and adsorption chromatography, respectively, with fluorescent spectrometric detection. The Ca and Mg concentration of the samples was determined by applying an inductively coupled plasma atomic emission spectrometric (ICP-AES) method. DIC-expressed in CO2 concentration values-was determined by using a CO2 selective electrode. According to the SEC analysis, the apparent molecular weight of the fulvic acids of the samples were between 500 and 1600 Da. The fulvic acid concentration values of the percolated water samples decreased in function of the soils investigated as follows: black rendzina>brown rendzina>red clayey rendzina>red clay, which is in concordance with the organic matter content of these types of soils. The results obtained for fulvic acid, Ca and Mg concentrations as well as for DIC, pH and electric conductivity of the water samples collected from the column filled with red clay were in good agreement with those of a seepage water sample collected from an observation station built in red clay above the Beke Cave (Aggtelek). Since the artificially prepared red clay column was exposed to the same temperature and humidity conditions like red clay of the sampling site, this method seems to be suitable for modelling infiltration of fulvic acid and metals from red clay into seepage water under laboratory conditions. (C) 2003 Elsevier B.V. All rights reserved

How types of carbonate rock assemblages constrain the distribution of karst rocky desertified land in Guizhou Province, PR China: Phenomena and mechanisms, 2004,
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Wang S. J. , Li R. L. , Sun C. X. , Zhang D. F. , Li F. Q. , Zhou D. Q. , Xiong K. N. , Zhou Z. F. ,
In Southwestern China karst rocky desertification (a process of land degradation involving serious soil erosion, extensive exposure of basement rocks, drastic decrease of soil productivity and the appearance of a desert-like landscape) results from irrational land use on the fragile, thin karst soil. Soil particles in the Guizhou karst plateau were accumulated predominantly from residues left behind after the dissolution of carbonate rocks, and the thickness of the soil layer is related to the amount of argillaceous substances in the lost carbonate rock. This paper examines the spatial distribution of karst rocky desertified (KRD) land in Guizhou Province, and relates it to the different assemblages of basement carbonate rocks. Types of carbonate rock assemblages are discussed using a 1 : 500000 scale digital-distribution map. Their distribution and sensitivity to erosion are analysed, demonstrating that the occurrence of KRD land is positively correlated to homogeneous carbonate rocks. Differences in physical and chemical properties of limestone and dolomite rocks lead to differences in dissolution, accumulation rate of soil particles and relief on the surface, and these factors influence land-use potential.

Speleothem organic matter content imaging. The use of a Fluorescence Index to characterise the maximum emission wavelength, 2005,
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Perrette Y. , Delannoy J. J. , Desmet M. , Lignier V. , Destombes J. L. ,
The study of palacoenvironments, especially pedologic and biologic environments, is fundamental to a complete understanding of continental climate changes. Many types of sediment contain organic molecules (OM) that were trapped during the depositional process, with the quantity and the nature of these organic molecules being strongly influenced by climate and other local factors. The quantity of organic matter in sediment can be measured by fluorescence intensity, but its nature is more difficult to determine. For this research, the organic molecules in stalagmites were analysed using emission fluorescence spectroscopy. The analysis of carbonated karst sediments was complemented by studies of clay, soil and seepage water samples. The main objective of this paper is to describe a method for the continuous imaging of the spectroscopic features of stalagmite organic molecules. Continuous imaging provides a means of circumventing the nonlinearity, both in space (of the sediment) and in time (of the sedimentation process), of the trapping of organic matter. This methodological report presents a protocol for calculating a Fluorescence Index (FI) that can be used in palaeoenvironmental studies of sediment. A similar approach to that used for determining E4/E6 ratios was used to determine the ratio of the fluorescence intensities of a sample at 514 nm and at 456 nm. This Fluorescence Index is strongly correlated to the wavelength of the maximum intensity of the organic matter spectrum. Due to the relatively stable chemical environment of calcite growth, changes in the Fluorescence Index can be interpreted as being due to changes in the nature of the organic molecules rather than to pH or quenching effects. As an illustration of how this index can be used, we present some examples of fluorescence indices for speleothem samples that show short-term and long-term environmental changes. To allow fuller palaeoenvironmental interpretations to be made, fluorescence indices need to be calibrated to environments and samples need to be dated. (C) 2004 Elsevier B.V. All rights reserved

Hydrogeological research as a basis for the preparation of the plan of monitoring groundwater contamination: A case study of the Stara vas landfill near Postojna (SW Slovenia), 2005,
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Petrič, Metka, Š, Ebela Stanka

For the present 9 landfills on karst are still active in Slovenia, among them also the Stara vas landfill near Postojna. As strong fissuration of the rock base and very good permeability is typical for karst areas, the waste waters from the landfills particularly endanger the groundwater. The capacity of natural filtration in karst is very low and the dimension of possible negative impact is very high. The actual legislation regulates the performance of operational monitoring, a part of which is also the measurement of parameters of contamination of groundwater by hazardous substances, if they are in the area of influence of the landfill. Preparation of the monitoring plan is based on adequate hydrogeological researches. Besides basic geological and hydrogeological data also the results of tracer tests were used in the case study of the Stara vas landfill. Additionally, the detailed tectonic-lithological mapping in the scale 1:5000 was performed in the narrow area of the landfill. Based on defined characteristics of underground water flow and in accordance with the regulations 3 monitoring points inside (Malenščica and Vipava springs, Fužina cave) and one point outside the area of influence of the landfill (Matijeva jama cave) were selected. The monitoring plan for the observation of water quality and capacity was suggested.


On the origin of fiber calcite crystals in moonmilk deposits, 2006,
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Canaveras Jc, Cuezva S, Sanchezmoral S, Lario J, Laiz L, Gonzalez Jm, Saizjimenez C,
In this study, we show that moonmilk subaerial speleothems in Altamira Cave (Spain) consist of a network of fiber calcite crystals and active microbial structures. In Altamira moonmilks, the study of the typology and distribution of fiber crystals, extracellular polymeric substances, and microorganisms allowed us to define the initial stages of fiber crystal formation in recent samples as well as the variations in the microstructural arrangement in more evolved stages. Thus, we have been able to show the existence of a relationship among the different types of fiber crystals and their origins. This allowed us to outline a model that illustrates the different stages of formation of the moonmilk, developed on different substrata, concluding that microbes influence physicochemical precipitation, resulting in a variety of fiber crystal morphologies and sizes

Minerogenetic mechanisms occurring in the cave environment: an overview, 2011,
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Onac Bogdan P. , Forti Paolo

Perhaps man’s first motivation to explore caves, beyond using them as shelter, was the search for substances that were not available elsewhere: most of them were minerals. However, for a long time it was believed that the cave environment was not very interesting from the mineralogical point of view. This was due to the fact that most cave deposits are normally composed of a single compound: calcium carbonate. Therefore, the systematic study of cave mineralogy is of only recent origin. However, although only a limited number of natural cavities have been investigated in detail, about 350 cave minerals have already been observed, some of which are new to science. The presence of such unexpected richness is a direct consequence of the variety of rocks traversed by water or other fluids before entering a cave and the sediments therein. Different cave environments allow the development of various minerogenetic mechanisms, the most important of which are double exchange reactions, evaporation, oxidation, hydration-dehydration, sublimation, deposition from aerosols and vapors, and segregation. The cave temperature and pH/Eh strictly control most of them, although some are driven by microorganisms. The cave environment, due to its long-term stability, can sometimes allow for the development of huge euhedral crystals, such as those found in the Naica caves (Mexico), but the presence of extremely small yet complex aggregates of different minerals is far more common. Future development in the field of cave mineralogy will likely be focused mainly on hydrothermal and sulfuric-acid caves and on the role played by micro-organisms in controlling some of the most important minerogenetic processes in caves


SPILLAGES OF HAZARDOUS SUBSTANCES ENDANGER KARST WATERS, 2011,
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Kogovek J. , Petrič, M.


Water Tracing in Karst Aquifers, 2012,
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Jones, William K.

Water tracer tests are usually conducted to establish the hydrologic connections between two or more points. The tracer is an identifiable label or marker added to flowing water that establishes the links between the injection point of the tracer and the monitoring points where the tracer reappears. Fluorescent dyes are the most commonly used tracers in karst aquifers, but a wide range of substances has been used successfully. The experimental design of a tracer test may be qualitative to simply establish if a hydrologic connection exists between two points, or quantitative to measure the time-concentration series (breakthrough curve) generated by the recovery of the tracer. Water tracer tests usually work well in karst areas because of the fast groundwater flow rates and the prevalence of flow paths restricted to discrete conduits.


Micro-Charcoal Abundances in Stream Sediments from Buckeye Creek Cave, West Virginia, USA, 2012,
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Springer G. S. , Mihindukulasooriya L. N. , White D. M. , Rowe H. D.

 

We compare micro-charcoal abundances in laminated cave-stream sediments to the presences of Native Americans and later settlers in the same watershed. Samples were obtained from a core taken from a 2.5 m high point bar located 1 km inside of Buckeye Creek Cave, West Virginia. Thirty-three subsamples were treated with hydrogen peroxide to bleach or whiten non-charcoal organic matter. In the absence of opaque mineral grains, this technique creates a large visual contrast between dark charcoal grains and other substances. The subsamples were photographed using a microscope-mounted camera, and pixels darker than 99/255 (grayscale) were used to calculate charcoal concentrations. The record spans the last 6,000 years, and four of the five highest charcoal concentrations are from the last 2,000 years. The highest concentration is from AD 1093, and the second-highest concentration is from the nineteenth century. Post-Colonial settlers began making extensive use of the watershed sometime in the eighteenth century and may, therefore, be responsible for the second-highest charcoal concentration. However, archaeologists independently concluded that Native Americans made peak use of the watershed between AD 1000 and 1200, which coincides with the highest charcoal concentration in the record. Native Americans are known to have extensively used fire, so there is good circumstantial evidence tying high concentrations in the last 2,000 years to human activities. Our method is suitable for use elsewhere, and we present a detailed statistical analysis of our data as a guide toward interpreting charcoal concentrations in karst and non-karst deposits.


Biodiversity and conservation of subterranean fauna fromPortuguese karst. Ph.D. Thesis, 2012,
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Ana Sofia Reboleira

This research is a contribution to the study of subterranean biodiversity in karst areas of Portugal, towards its conservation.

The relative inaccessibility of the subterranean environment is a challenge for the study of its fauna, often accessible only in caves but more widely distributed. The subterranean animals are among the most rare, threatened and worldwide underprotected, often by the simple fact of being unknown.

Karst areas of Portugal occupy a considerable part of the territory and harbor more than 2000 caves. The complex biogeographical history of the Iberian Peninsula allowed the survival of several relict arthropod refugees in the subterranean environment.

Subterranean invertebrates have been ignored, as for as the protection of karst systems are concerned in Portugal, largely because knowledge was scarce and disorganized. Reviewing all the bibliographic sources about subterranean fauna from Portugal and listing troglobiont and stygobiont species and locations, was essential to understand the state of knowledge of species richness and the biogeography and conservation status for the studied areas.

In order to understand subterranean biodiversity patterns in karst areas from Portugal, one year of intense fieldwork was performed in more than 40 caves from 14 karst units. Several new species for science were discovered and 7 taxa comprising 2 new genera and 5 new species were described.

Bearing in mind that spatial distribution of subterranean species is crucial to ecological research and conservation, the distribution of hypogean species, from Portuguese karst areas, was mapped using geographic information systems. Also, its subterranean richness was compared with other areas of the world and missing species were estimated on a regional scale. The subterranean biodiversity patterns were analyzed, and several factors were tested to explain richness patterns. Evapotranspiration and the consequent high productivity on the surface may be determinant in the species richness in the different karst units of Portugal, but the depth of the caves and the unique geological features of every massif seemed to play a more important role.

In order to evaluate the tolerance of organisms to groundwater contamination, the acute toxicity of two substances were tested on stygobiont crustaceans with different degrees of troglomorphism. Our study showed that the high levels of endemism contribute to remarkably different toxicological responses within the same genus.

The major problems related to conservation of subterranean habitats were associated to direct destruction and their contamination. These ecosystems lack of specific protection, implying an adequate management of surface habitats and the establishment of priority areas. Integrating all the previous information, this study establishes a ranking of sites for conservation of subterranean fauna in karst areas of Portugal.This research is a contribution to the study of subterranean biodiversity in karst areas of Portugal, towards its conservation.

The relative inaccessibility of the subterranean environment is a challenge for the study of its fauna, often accessible only in caves but more widely distributed. The subterranean animals are among the most rare, threatened and worldwide underprotected, often by the simple fact of being unknown.

Karst areas of Portugal occupy a considerable part of the territory and harbor more than 2000 caves. The complex biogeographical history of the Iberian Peninsula allowed the survival of several relict arthropod refugees in the subterranean environment.

Subterranean invertebrates have been ignored, as for as the protection of karst systems are concerned in Portugal, largely because knowledge was scarce and disorganized. Reviewing all the bibliographic sources about subterranean fauna from Portugal and listing troglobiont and stygobiont species and locations, was essential to understand the state of knowledge of species richness and the biogeography and conservation status for the studied areas.

In order to understand subterranean biodiversity patterns in karst areas from Portugal, one year of intense fieldwork was performed in more than 40 caves from 14 karst units. Several new species for science were discovered and 7 taxa comprising 2 new genera and 5 new species were described.

Bearing in mind that spatial distribution of subterranean species is crucial to ecological research and conservation, the distribution of hypogean species, from Portuguese karst areas, was mapped using geographic information systems. Also, its subterranean richness was compared with other areas of the world and missing species were estimated on a regional scale. The subterranean biodiversity patterns were analyzed, and several factors were tested to explain richness patterns. Evapotranspiration and the consequent high productivity on the surface may be determinant in the species richness in the different karst units of Portugal, but the depth of the caves and the unique geological features of every massif seemed to play a more important role.

In order to evaluate the tolerance of organisms to groundwater contamination, the acute toxicity of two substances were tested on stygobiont crustaceans with different degrees of troglomorphism. Our study showed that the high levels of endemism contribute to remarkably different toxicological responses within the same genus.

The major problems related to conservation of subterranean habitats were associated to direct destruction and their contamination. These ecosystems lack of specific protection, implying an adequate management of surface habitats and the establishment of priority areas. Integrating all the previous information, this study establishes a ranking of sites for conservation of subterranean fauna in karst areas of Portugal.


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