Data for: What actually controls the minute to hour changes in soil carbon dioxide concentrations?

Data on changes in soil carbon dioxide concentrations

Data for: What actually controls the minute to hour changes in soil carbon dioxide concentrations?

Data on changes in soil carbon dioxide concentrations

Corrosion of calcite speleothems in epigenic caves of Moravian Karst (Czech Republic)

The data are part of the article ‘Corrosion of calcite speleothems in epigenic caves of the Moravian Karst (Czech Republic)’ accepted for publication in the journal Environmental Earth Sciences (Springer). The results are based on a comparison of the natural corrosion of calcite speleothem with the artificial corrosion of limestone and calcite standards. A new mechanism of corrosion is presented. Conditions of corrosion are demonstrated on conceptual model of the karst vertical profile.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Historical ferrous slag induces modern environmental problems in the Moravian Karst (Czech Republic)

Ferrous slag produced by a historic smelter is washed from the heap and transported by a creek through the cave system. There is concern that the slag fills cave spaces, abrades cave walls / calcite speleothems, and contaminates the aquatic environment with heavy metals and other toxic components. The study objectives were to better characterize the slag in its deposition site, map its transport through the cave system, characterize the effect of slag transport, and to judge the risks to both cave and aqueous environments. The study was based on methods of chemical and phase analysis supported laboratory experiments and geochemical modeling. The slag in the heap was dominated by amorphous glass phase (66 to 99 wt%) with mean composition of 49.8±2.8 wt% SiO2, 29.9±1.6 wt% CaO, 13.4±1.2 wt% Al2O3., 2.7±0.3 wt% K2O and 1.2±0.1 wt% MgO. Minerals such as melilite, plagioclase, anorthite, and wollastonite / pseudowollastonite with smaller amounts of quartz, cristobalite, and calcite were detected. Slag trace elements formally enrich the cave environment with Se, As, W, Y, U, Be, Cs, Sc, Cd, Hf, Ba, Th, Cr, Zr, Zn, and V. However, only Zr, V, Co, and As exceed specified limits for soils (US EPA and EU limits). The life of a 1 mm3 volume of slag was estimated to be 27,000 years. The mean residence time of the slag in the cave defined by the flood frequency was 47 years. The main conclusion was that the extent of slag weathering is small and that the slag does not contaminate the cave aqueous environment under given conditions. However, the slag enriched in U / Th can increase radon production as a result of alpha decay. The slag has an abrasive effect on surrounding rocks and disintegrated slag can contaminate calcite speleothems.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Karst caves, a global exchanger of carbon dioxide

Data from the Sloup-Šošůvka Caves (Moravian Karst)THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

The geochemistry and origin of fluids in the carbonate structure of the Hranice Karst with the world\u27s deepest flooded cave of the Hranicka Abyss, Czech Republic

The origin of fluids in the Hranice Karst containing the deepest flooded abyss in the world has been investigated using hydrogeological, hydrogeochemical, and isotopic data. At least a part of the CO2 gas originates in the mantle as indicated by very enriched δ13C(DIC) values and from existing He isotope analyses. The origin of groundwater in the karstic aquifer which is exploited at the Teplice nad Bečvou Spa is meteoric with a recharge area about 200 m above the Bečva River valley as indicated by depleted values of δ2H and δ18O compared to the river water. Based on detectable tritium, the groundwater is from 20 to 50 years old. Water in the Hranicka Abyss and in the Zbrašov Aragonite Caves is a mixture of carbonate aquifer groundwater with the river and/or shallow groundwater comprising variable proportions of both end-members. Water in Death Cave Lake seems to be affected by agriculture contaminated shallow groundwater as indicated by increased nitrate concentration. Inverse geochemical modeling of aquifer geochemistry suggested two scenarios: (1) reaction of Mg-rich calcite with deep hypogenic CO2 (about 30 mmol/l) plus dissolution of trace amounts of halite and sylvite and cation exchange; (2) reaction of Mg-depleted calcite and Mg-silicate (talc) as a source of Mg together with deep CO2. Both scenarios were calibrated using δ13C(DIC) values and gave satisfactory results. A conceptual model of the site has been developed which includes a gravity-driven flow system where meteoric water which has recharged in the surrounding uplands is heated at depth and acquires large amounts of hypogenic CO2, which preferentially dissolves Mg-carbonates along the pre-existing tectonic features. The Miocene transgression followed by the later incision of the Bečva Valley played an important role in groundwater circulation and the origin of fluids

Environmentally acceptable effect of hydrogen peroxide on cave “lamp-flora”, calcite speleothems and limestones

Mosses, algae, and cyanobacteria (lamp-flora) colonize illuminated areas in show caves. This biota is commonly removed by a sodium hypochlorite solution. Because chlorine and other deleterious compounds are released into a cave environment during lamp-flora cleansing, hydrogen peroxide was tested as an alternative agent. In a multidisciplinary study conducted in the Kateřinská Cave (Moravian Karst, Czech Republic), 12 algae- and cyanobacteria taxons and 19 moss taxons were detected. The threshold hydrogen peroxide concentration for the destruction of this lamp-flora was found to be 15 vol.%. Based on laboratory experiments in stirred batch reactors, the dissolution rates of limestones and calcite speleothems in water were determined as 3.77×10−3 and 1.81×10−3 mol m−2 h−1, respectively. In the 15% peroxide solution, the limestone and speleothem dissolution rates were one order of magnitude higher, 2.00×10−2 and 2.21×10−2 mol m−2 h−1, respectively. So, the peroxide solution was recognised to attack carbonates somewhat more aggressively than karst water. In order to prevent the potential corrosion of limestone and speleothems, the reaching of preliminary peroxide saturation with respect to calcite is recommended, for example, by adding of few limestone fragments into the solution at least 10 h prior to its application