The main objective of this study is to analyse the effect of tendencies in the meteorological variables on the water quality on the example of five lakes in the Aggtelek and Slovak karst. The data set used eleven water quality parameters (oxygen saturation, chemical oxygen demand, nitrate, nitrite, orthophosphate, total phosphorus, ammonium, pH, conductivity, iron, manganese), as well as daily data of six climatic parameters from the period 2008­2010. A cluster analysis is performed in order to determine the climate impact on the water quality parameters. Furthermore, factor analysis with special transformation, as a novelty in the study, is implemented to find out the weight of the climate parameters as explanatory variables and hence their rank of importance in forming the given water quality parameter as an influencing variable. The study introduces a methodology for analysing the climate impact on the water quality parameters. In order to reduce the number of the water quality parameters, a so called two­stage factor analysis was performed, which is a novel procedure. Application of the two­stage factor analysis involves both benefits and disadvantages. Its benefit is that it substantially reduces the number of resultant variables. In this way, information loss of the retained factors is around 20%. As a result, we received that both positive and negative extreme values of water quality parameters can be associated with weak or breaking­up warm fronts passing through over the region. On the contrary, the role of anticyclones or anticyclone ridge weather situations is supposed to be irrelevant. Unstable and extreme weather conditions act in the direction of breaking up the balance that would support the good water quality. This process does not benefit the water use nor the sensitive karst hydrogeological system

No-mount Cave, located in wekiwa Springs State Park in central Florida, USA, is an aphotic, submerged, freshwater cave in which large colonies of sulfur-oxidizing bacteria live in filamentous microbial mats. Upwardly discharging groundwater enters the cave from the Upper Floridan aquifer, specifically the Eocene-aged Ocala Limestone. we undertook a combined field, laboratory, and modeling study in which we sought to determine the amount of calcite dissolution attributable to the generation of protons by microbially mediated sulfide oxidation. The chemical compositions of groundwater within the limestone formation collected through a newly designed sampling device and of water in the cave conduit were used in geochemical modeling. we used the reaction-path model PHREEqCI to quantify the amount of calcite dissolution expected under various plausible scenarios for mixing of formation water with conduit water and extent of bacterial sulfide oxidation. Laboratory experiments were conducted using flow-through columns packed with crushed limestone from the study site. Replicate columns were eluted with artificial groundwater containing dissolved HS- in the absence of microbial growth. without biologically mediated sulfide oxidation, no measurable calcite dissolution occurred in laboratory experiments and no additional amount of speleogenesis is expected as formation water mixes with conduit water in the field. In contrast, significant calcite dissolution is driven by the protons released in the biological transformation of the aqueous sulfur species. Although a range of results were calculated, a plausible amount of 158 mg Ca2+ released to conduit water per liter of groundwater crossing the formation-conduit boundary and mixing with an equal volume of conduit water was predicted. Our modeling results indicate that significant cave development can be driven by microbially mediated sulfide oxidation under these hydrogeochemical conditions

Clay cortex from the contact zone between the host rock (chalk) and infilling deposits were examined in

paleokarst forms (pockets, pipes, and dolines of different age) from the Lublin–Volhynia chalk karst region. In light of the sedimentological and micromorphological analyses, it seems possible to work out a model as the basis for genetic and stratigraphic discussions. (1) Dolineswith the Paleogene orNeogene mineral infills are characterized by (a) homogeneous, residual type of massive clay gradually passing into the chalkmonolith, and at the sametime(b) relatively thickweathered zone. (2) Pipeswith glacigenic mineral infill fromthe Saalian Glacial are characterized by (a) sharp contact between host rock and clay, (b) narrow weathering zone of chalk, (c) diffuse nature of the contact zone between residual clay and mineral infill, and (d) contamination of clay by clastic material. (3) Pocketswith glacigenic mineral infill and traces of theWeichselian periglacial transformation are characterized by (a) strong contamination of chalk by quartz grains, (b) diffuse transition between clay and infill: fromclayey matrixwith single quartz grains (at the contactwith chalk) to clayey coatings and intergranular bridges (in the infill), (c) intensive weathering (cracking) of mineral grains in the infill.

The aim of this study is to characterize in detail, the mineralogy of different-shaped concretions as well as to investigate the physico-chemical parameters of the associated mine drainage and drip waters in the Santa Barbara level of the Libiola Mine (NW Italy) by several geochemical and mineralogical techniques. Under the term “minothems” we are grouping all those secondary minerals that occur under certain form or shape related to the conditions under which they formed but occur in a mine, or in any artificial underground environment (i.e., "mine speleothems"). Different types of minothems (soda straw stalactites, stalactites, and draperies) were sampled and analyzed. Mineralogical results showed that all the samples of stalactites, stalagmite and draperies are characterized by poorly crystalline goethite. There are significant differences either in their texture and chemistry. Stalactites are enriched in Zn, Cd, and Co in respect to other minothems and show botryoidal textures; some of these exhibit a concentric layering marked by the alternation of botryoidal and fibrous-radiating textures; the draperies are enriched in V and show aggregates of sub-spheroidal goethite forming compact mosaic textures. Geochemical investigations show that the composition and physico-chemical parameters of mine drainage and drip waters are different from the other acidic mine water occurrences in different areas of the Libiola Mine, where minothems are less abundant. All mine water samples contain Cu, Ni, and Zn in appreciable levels, and the physico-chemical conditions are consistent with the stability of ferrihydrite, which however tends to transform into goethite upon ageing.