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Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
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 nitrate (Keyword) returned 78 results for the whole karstbase:
Showing 16 to 30 of 78
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A groundwater catchment, located in Woodford and Jessamine Counties in the Inner Bluegrass of Kentucky, was instrumented to develop long-term flow and water quality data. The land uses on this 1 620-ha catchment consist of approximately 59% in grasses consisting of beef farms, horse farms, and a golf course; 16% row crops; 6% orchard; 13% forest; and 6% residential. Water samples were analyzed twice a week for, Ca, Mg, Na, Cl-, HCO3-, SO4=, NO3-, total solids, suspended solids, fecal coliforms, fecal streptococci, and triazines. Flow rate and average ambient temperature were also recorded. No strong linear relationship was developed between chemical concentrations and other parameters. The transient nature of the system was emphasized by one event that drastically deviated from others. Pesticide data were summarized and the ''flushing'' phenomena accredited to karst systems was discussed. The total solids content in the spring was consistent at approximately 2.06 mg/L. Fecal bacteria contamination was well above drinking water limits (fecal coliform and fecal streptococci averages were 1 700 and 4 300 colony-forming-units/100 mL, respectively) and the temporal variation in bacterial contamination was not linked to any other variable
The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian Region. Karst areas comprise about 18 percent of the Region's land area. An estimated one-third of the Region's farms, cattle, and agricultural market value are on karst terrain. Nitrate concentrations were measured in cave streams draining two primary land management areas. The first area was pasture serving a beef cow-calf operation. The second area was a dairy. Nitrate-N concentrations were highest in cave streams draining the daily and a cave stream draining an area of pasture where cattle congregate for shade and water. The dairy contributed about 60 to 70 percent of the nitrogen load increase in the study section of the cave system. It was concluded that agriculture was significantly affecting nitrate concentrations in the karst aquifer. Best management practices may be one way to protect the ground water resource
Ground water and surface water constitute a single dynamic system in most parts of the Suwannee River basin due to the presence of karst features that facilitate the interaction between the surface and subsurface. Low radon-222 concentrations (below background levels) and enriched amounts of oxygen-18 and deuterium in ground water indicate mixing with surface water in parts of the basin. Comparison of surface water and regional ground water flow patterns indicate that boundaries for ground water basins typically do not coincide with surface water drainage subbasins. There are several areas in the basin where around water flow that originates outside of the Suwannee River basin crosses surface water basin boundaries during both low-flow and high-flow conditions. In a study area adjacent to the Suwannee River that consists predominantly of agricultural land use, 18 wells tapping the Upper Floridan aquifer and 7 springs were sampled three times during 1990 through 1994 for major dissolved inorganic constituents, trace elements, and nutrients. During a period of above normal rainfall that resulted in high river stage and high ground water levels in 1991, the combination of increased amounts of dissolved organic carbon and decreased levels of dissolved oxygen in ground water created conditions favorable for the natural reduction of nitrate by denitrification reactions in the aquifer. As a result, less nitrate was discharged by ground water to the Suwannee River
Military institutions involved in the production and demolition of explosives, propellants, and pyrotechnics have the potential to degrade groundwater aquifers through the addition of numerous contaminants including nitrate. A nitrate plume has been identified in a karst aquifer beneath the Ammunition Burning Ground (ABG) at the Crane Naval Surface Warfare Center, Indiana, USA. Wells located in the vicinity of surface impoundments and bum pans used for treatment of explosive materials show the highest concentrations of nitrate ranging from 11.2 to 19.6 mg l(-1) as NO3-. Little is known about the isotopic composition of nitrates originating from these processes. Eight wells within the ABG were sampled and analyzed for nitrogen isotopic composition of nitrate. An enrichment in the delta(15)N (delta(15)N = .9, .0, .1. and .5 parts per thousand) occurred at four wells located near the primary areas of disposal activities within the ABG. Four wells located near the outer limits of the ABG had delta(15)N values significantly lower than those observed in the central area of the ABG (delta(15)N = .0, .1, .6, and .0 parts per thousand). Soil samples and burn-pan ash samples were collected and analyzed for the nitrogen isotopic composition of nitrate. Three soil nitrate samples had low delta(15)N values of -1.7, -1.8. and .2 parts per thousand. The burn-pan ash sample produced nitrate with a delta(15)N value of .9 parts per thousand. The observed enrichment in delta(15)N from samples taken from wells located near the ABG has been postulated to be a result of photodegradation or biochemical modification of RDX and TNT contaminated sludges and volatilization of NH3 in storage lagoons within the ABG. (C) 1998 Elsevier Science B.V. All rights reserved
The aim of this paper is to appraise the ability of the oxidation of riverine organic matter in the control of limestone dissolution, in a karst network. Biogeochemical processes during infiltration of river water into an alluvial aquifer have already been described for an average flow velocity of 4-5 m d(-1) (Jacobs, L. A., von Gunten, H. R., Keil, R, and Kuslys, M. (1988) Geochemical changes along a river-groundwater infiltration flow path: Glattfelden, Switzerland. Geochim. Cosmochim. Acta 52, 2693-2706; Von Gunten, H. R., Karametaxas, G., Krahenbuhl, U., Kuslys, M., Giovanoli R., Hoehn E. and Keil R. (1991) Seasonal biogeochemical cycles in riverborne groundwater. Geochim. Cosmochim. Acta 55, 3597-3609; Bourg, A. C. M. and Bertin, C. (1993) Quantitative appraisal of biogeochemical chemical processes during the infiltration of river water into an alluvial aquifer. Environ. Sci. Technol. 27, 661-666). Karstic drainage networks, such as in the River Loire-Val d'Orleans hydrologic system (Fig. 1), make possible flow velocities up to 200 m h(-1 a) and provide convenient access to different water samples several tens of km apart, at both extremities of the hydrologic unit (Chery, J.-L. (1983) Etude hydrochimique d'un aquifere karstique alimente par perte de cours d'eau (la Loire): Le systeme des calcaires de Beauce sous le val d'Orleans. These, Universite d'Orleans; Livrozet, E. (1984) Influence des apports de la Loire sur la qualite bacteriologique et chimique de l'aquifere karstique du val d'Orleans. These, Universite d'Orleans). Recharge of the karstic aquifer occurs principally from influent waters from stream sinks, either through coarse alluvial deposits or directly from outcrops of the regional limestone bedrock (Calcaires de Beauce). Recharge by seepage waters From the local catchment basin is small (Zunino, C., Bonnet, M. and Lelong, F. (1980) Le Val d'Orleans: un exemple d'aquifere a alimentation laterale. C. R. somm. Soc. Geol. Fr. 5, 195-199; Gonzalez R. (1992) Etude de l'organisation et evaluation des echanges entre la Loire moyenne et l'aquifere des calcaires de Beauce. These, Universite d'Orleans) and negligible in summer. This karstic hydrologic: system is the largest in France in terms of flow (tens to hundreds of m(3)/s) and provides the main water resource of the city of Orleans. Chemical compositions of influent waters (River Loire) and effluent waters (spring of the river Loiret) were compared, in particular during floods in summer 1992 and 1993 (Figs 2-4). Variation of chloride in the River Loire during the stream rise can be used as an environmental tracer of the underground flow (Fig. 2). Short transit times of about 3 days are detectable (Fig, 2) which are consistent with earlier estimations obtained with chemical tracers (Ref. in Chery, J.-L. (1983) These, Universite d'Orleans). Depending on the hydrological regime of the river, organic carbon discharge ranges between 3-7 and 2-13 mg/l for dissolved and particulate matter respectively (Fig. 3). Eutrophic characteristics and high algal biomasses are found in the River Loire during low water (Lair, N. and Sargos, D. (1993) A 10 year study at four sites of the middle course of the River Loire. I - Patterns of change in hydrological, physical and chemical variables in relation to algal biomass. Hudroecol. Appl. 5, 1-27) together with more organic carbon rich suspended particulate matter than during floods (30-40 C-org % dry weight versus 5-10%). Amounts of total organic carbon and dissolved oxygen (Fig. 3) dramatically decrease during the underground transport, whereas conversely, dissolved calcium, alkalinity and inorganic carbon increase (Fig. 4). Anoxia of outflows map start in April. Dissolution of calcium carbonates along the influent path outweighs closed system calcite equilibrium of inflow river waters (Table 3). The impact of organic matter oxidation on calcite dissolution may be traced by variations of alkalinity and total carbonates in water. Following, Jacobs, L. A., von Gunten, H. R., Keil, R. and Kuslys, M. (1988) Geochemical changes along a river-groundwater infiltration flow path: Glattfelden, Switzerland. Geochim. Cosmochim. Acta 52, 2693-2706), results are shown graphically (Fig. 5). Extent of reactions is controlled by the consumption of dissolved O-2 and nitrate for organic matter oxidation and by the release of Ca2 for calcite dissolution (Table 2). The karstic network is considered to behave like a biological reactor not exchanging with the atmosphere, with steady inhabitant microbial communities (Mariotti A., Landreau A, and Simon B. (1988) N-15 isotope biogeochemisrry and natural denitrification process in groundwater: Application to the chalk aquifer of northern France. Geochim. Cosmochim. Acta 52, 1869-1878; Gounot, A.-M. (1991) Ecologie microbienne des eaux ei des sediments souterrains. Hydrogeologie, 239-248). Thus, energy requirements only are considered, not carbon assimilation. Moreover, there is no necessity to invoke any delay for nitrification enhancement, as observed elsewhere, after waste water discharge into the river (Chesterikoff, A., Garban, B., Billen, G. and Poulin, M. (1992) Inorganic nitrogen dynamics in the River Seine downstream from Paris (France). Biogeochem. 17, 147-164). Main microbial processes are assumed to be aerobic respiration, nitrification and denitrification. Reactions with iron and manganese, real but not quantitatively important, were neglected. Sulphate reduction and methane formation, certainly not active, were not considered. Denitrification, which is suggested by low nitrate and ammonium concentrations and anoxia in the outflow, is known to be rapid enough to be achieved in a short time (Dupain, S. (1992) Denitrification biologique heterotrophe appliquee au traitement des eaux d'alimentation: Conditions de fonclionnement et mise au point d'un procede. These, Universite Claude Bernard, Lyon). Reaction are somewhat arbitrary but conform to general acceptance (Morel, M. M. and Hering, J. G. (1993) Principles and Applications of Aquatic Chemistry. Wiley, New York). Anaerobic ammonium oxidation (Mulder A., van de Graaf, A. A., Robertson, L: A. and Kuenen, J. G. (1995) Anaerobic ammonium oxidation discovered in a denitrifying fluidized bed reactor. FEMS Microbiol. Ecol. 16, 177-184). although possible, was not considered. In fact, C/N ratio of the reactive organic matter has only mild repercussions on the results; i.e. in the same range as the analytical errors for alkalinity and total carbonates. The objective was simply to roughly confront characteristics of outflowing waters and the calculation. Respective roles of aerobes and denitrifiers, for instance, are not certain. Several periods during low water or floods were selected with various ranges for calcium dissolution or nitrate and oxygen concentrations. The result is that in most cases simulation and data are in reasonable accordance (Fig. 5). Amounts of organic matter in River Loire are generally sufficient to sustain the process (Table 3. Particulate organic matter is probably the most reactive. The balance of oxidation of organic matter indicates that about 65 mu g C-org/l.h are oxidized during the transport without much variation with the river regime or organic discharge. It is concluded that limestone dissolution is directly dependent on organic matter oxidation, but variation occurs (7-29 mg CuCO3/l) with the level of bases that can be neutralized in the River Loire water. (C) 1998 Elsevier Science Ltd. All rights reserved
In 1986 and 1987 seven series of samples were taken at 36 to 47 sampling points on Babno, Loško and Cerkniško Polje and on Bloke and at Loški potok in order to find out their physico-chemical properties and their quality. Rainwater flows from the limestone and dolomite landscape around Babno, Loško and Cerkniško polje into springs feeding the sinking streams. The nitrate level at most of the springs was below 4 mg NO3-/l and chloride below 5 mg Cl-/l; the o-phosphate level varied around the value of 0.05 mg PO43-/l. The bacteriological analyses of the spring waters showed that they are not of drinking quality and only few springs were seasonally of good quality. Poorer quality was found in springs with populated catchments, such as are Pudobski Izvir, Podgorski and Mežnarjev Studenec and, obviously in all the sinking waters at swallow-holes where the nitrate and chloride level was up to 20 mg/l and phosphate up to 5 mg/l. Flowing over karst poljes this water receives pollution due to habitations and industry. As the water of these sinking streams reappears downstream in several lower-lying karst poljes this results in the transport and accumulation of pollution downstream even in springs that are captured for water supply.
The mineralogy of Kartchner Caverns is both diverse and significant. Six different chemical classes are represented in this one cave: carbonates, nitrates, oxides, phosphates, silicates, and sulfates. It is significant primarily because: (1) the silicate minerals, nontronite and rectorite, have never before been reported from a cave occurrence; (2) the nitrate mineral, nitrocalcite, has never been described using modern techniques; (3) ‘birdsnest’ needle quartz has been reported only from one other, non-cave, locality; and (4) extensive brushite moonmilk flowstone has not been reported from anywhere else in the world. Kartchner is a beautiful cave because its carbonate speleothems are colorful (shades of red, orange, yellow and tan) and ‘alive’ (still wet and growing).
The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian Region. Karst areas comprise about 18 percent of the Region's land area. An estimated one-third of the Region's farms, cattle, and agricultural market value are on karst terrain. The purpose of this study was to compare fecal bacteria densities in karst groundwater impacted by two primary agricultural land uses in central Appalachia. Fecal bacteria densities were measured in cave streams draining two primary land management areas. The first area was pasture serving a beef cow-calf operation. The second area was a dairy. Neither area had best management practices in place for controlling animal wastes. Median fecal coliform and fecal streptococcus densities were highest in cave streams draining the dairy. Median fecal coliform densities in the daily-impacted stream were greater than 4,000 CFU/100 ml and the median fecal coliform densities in the pasture-impacted streams were less than TO CFU/100 ml. Median fecal streptococcus densities in the same streams were greater than 2,000 CFU/100 ml and 32 CFU/100 ml, respectively. A second dairy, with best management practices for control of animal and milkhouse waste, did not appear to be contributing significant amounts of fecal bacteria to the karst aquifer. It was concluded that agriculture was affecting bacterial densities in the karat aquifer. New management practices specifically designed to protect karst groundwater resources may be one way to protect the groundwater resource
The Celtic regions of Britain and Ireland have a complex and diverse geology which supports a range of regionally and locally important bedrock aquifers and unconsolidated Quaternary aquifers. In bedrock, aquifer units are often small and groundwater flow paths short and largely reliant on fracture flow. Groundwater has fulfilled an important social role throughout history, and is now enjoying renewed interest. Groundwater quality is generally favourable and suitable for drinking with minimal treatment. However, many wells are vulnerable to microbiological and chemical pollutants from point sources such as farmyards and septic tank systems, and nitrate concentrations from diffuse agricultural sources are causing concern in certain areas. Contamination by rising minewaters in abandoned coalfields and in the vicinity of abandoned metal mines is also a problem in some of the Celtic lands
Geochemical data indicate that the Springfield Plateau aquifer, a carbonate aquifer of the Ozark Plateaus Province in central USA, has two distinct hydrochemical zones. Within each hydrochemical zone, water from springs is geochemically and isotopically different than water from wells. Geochemical data indicate that spring water generally interacts less with the surrounding rock and has a shorter residence time, probably as a result of flowing along discrete fractures and solution openings, than water from wells. Water type throughout most of the aquifer was calcium bicarbonate, indicating that carbonate-rock dissolution is the primary geochemical process occurring in the aquifer. Concentrations of calcium, bicarbonate, dissolved oxygen and tritium indicate that most ground water in the aquifer recharged rapidly and is relatively young (less than 40 years). In general, field-measured properties, concentrations of many chemical constituents, and calcite saturation indices were greater in samples from the northern part of the aquifer (hydrochemical zone A) than in samples from the southern part of the aquifer (hydrochemical zone B). Factors affecting differences in the geochemical composition of ground water between the two zones are difficult to identify, but could be related to differences in chert content and possibly primary porosity, solubility of the limestone, and amount and type of cementation between zone A than in zone B. In addition, specific conductance, pH, alkalinity, concentrations of many chemical constituents and calcite saturation indices were greater in samples from wells than in samples from springs in each hydrochemical zone. In contrast, concentrations of dissolved oxygen, nitrite plus nitrate, and chloride generally were greater in samples from springs than in samples from wells. Water from springs generally flows rapidly through large conduits with minimum water-rock interactions. Water from wells flow through small fractures, which restrict how and increase water-rock interactions. As a result, springs tend to be more susceptible to surface contamination than wells. The results of this study have important implications for the geochemical and hydrogeological processes of similar carbonate aquifers in other geographical locations. Copyright (C) 2000 John Wiley & Sons, Ltd
Recent investigations of drinking water quality related to the spring Mrzlek near Solkan, Slovenia are described. Multielemental analyses of 66 elements and anions such as nitrate, nitrite, sulphate, chloride, phosphate, bromide and fluoride in water from the spring Mrzlek and the river Soča, as well as determination of trihalomethanes in chlorinated water, were carried out to reveal eventual impacts of environmental pollution on the quality of drinking water from spring Mrzlek. It was observed that the pollution of the river Soča with heavy metals is recently decreasing, while the concentrations of trihalomethanes in drinking water are relatively low and have not increased during the last five years. At present the quality of drinking water from the spring Mrzlek meets all the standards. Higher concentrations of nitrate in the spring, however, indicate potential pollution from farming on the Banjšice plateau. In general, quite similar concentrations of most elements and anions were observed in the spring Mrzlek and the river Soča. Higher concentrations of Ca, Fe, Zn, nitrate and chloride were observed in the spring, while concentrations of Mn, Mg, Ba, As, and sulphate were significantly higher in the river.
The paper presents a synthesis of LNEC's contribution to the European Commission (DGXII) Contract n° CI1*-CT94-0014 (DG 12 HSMU), based on the results reported by Lobo-Ferreira et al. (1998). The main contribution of LNEC to the project was the development of flow and transport experiments, for different flow type conditions (i.e. saturated and unsaturated). These included experiments at: (1) different scales (two scales in the laboratory and one in a medium scale - artificial aquifer), (2) different saturation conditions, and (3) different tracers (MgCl2, CaCl2, NO3-, Ni, Cd). The goals of the experiments were threefold: (1) analysis and quantification of the physical parameters that control circulation in this zone (hydraulic conductivity correspondent to the degree of saturation etc.); (2) determination and quantification of the more important processes that control the chemical behaviour of heavy metals and nitrate, and (3) to obtain data for calibrating the numerical models.
Water flow and contaminant transport from soil to underlying fractured rock is mainly controlled by the hydraulic conditions of the soil-bedrock boundary. In respect to the necessary understanding of contaminant transport at the soil-bedrock boundary the identification of flow paths within both the soil cover and the fractured media is decisive on the one side. On the other hand substance-specific behaviour of the often reactive pollutants compared to water flow has to be known in detail. Field scale tracer tests with different tracers (uranine and salts) and a potential pollutant as a reactive tracer (nitrate) were performed at the IRGO field research facility Sinji Vrh (SI). Injection points are located on the surface, in the soil, at the soil-rock interface and in the fractured rock; water is sampled in an underground tunnel with the help of two subhorizontal boreholes equipped with sampling devices and a special construction for collecting water seeping from the ceiling. The goal of these experiments is to identify the flow paths of solutes to the underground tunnel and to estimate their residence time dependent on the injection point. So far only some conclusions regarding the waterflux into the tunnel could be drawn.
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