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Tumajer J.,Charles University | Burda J.,Brown Coal Research Institute | Treml V.,Charles University
IAWA Journal | Year: 2015

Vessel lumen area is influenced by both genetic and environmental forces. Its alterations balance hydraulic water transport efficiency and safety from cavitation or embolism. We tested the hypothesis that environmental stress inflicted by rockfall injury influences average vessel lumen area in newly formed tree rings of Betula pendula Roth, which would make it useful for retrospective detection of rockfall events. We took samples from 11 trees injured by a rockfall that occurred in the winter of 2010-2011, specifically from the stem area adjacent to the injury, parts of the stem located perpendicular to the injury, parts located opposite to the injury, and from four undisturbed trees. We measured the mean vessel lumen area of each tree ring in every sample, comprising up to 10 pre-event tree rings and generally 3 tree rings formed after rock injury. On average, 115 vessels were measured in each tree ring. We then compared the vessel lumen area in tree rings formed after the event with that of rings formed before it as well as with values predicted by an age-trend model inferred from vessel lumen area chronologies. Our results show a strong reduction in vessel lumen area in the first tree ring formed after the event regardless of the position around the stem circumference. This reduction is strongest in wood just next to the callus tissue zone, with decreasing significance in distal parts of the stem circumference. During the three years after the rockfall, the trees mostly recovered their pre-event vessel lumen area, even right next to the place of injury. Still, this value is significantly lower than the value predicted for growth without injury. Abrupt reductions of vessel lumen area turn out to be potentially useful for identifying former rockfall events and can improve on results obtained by traditional methods of dendrogeomorphological dating. © 2015 by Koninklijke Brill NV, Leiden, The Netherlands. Source


Brejcha J.,Brown Coal Research Institute
12th International Multidisciplinary Scientific GeoConference and EXPO - Modern Management of Mine Producing, Geology and Environmental Protection, SGEM 2012 | Year: 2012

Development of procedures assessing the impact of hydrological reclamation of open mines on microclimate, water and soil ecosystems and air quality is the aim of the project. Unique opportunity of an ongoing hydrological reclamation of the open residual pit of the Most mine which significantly exceeds the reclamations being made in the Czech Republic, has been being utilized. The project started in 2011 and is scheduled for 4 years. Significance of air quality changes near a lake caused by microclimate changes of the area of interest is evaluated in a partial project which deals with air quality. Measurement is carried out in two zones and one reference point. Near vicinity of the lake is the first zone where 8 monitoring stations are situated ca 50 - 100 m from the lake bank. Further surroundings are the second zone where 3 monitoring stations are situated ca 50 - 100 m from the lake bank. The reference point is 20 km distant from the locality. The concentrations of characteristic pollutants for this industrial locality are observed - SO2, NOx, O3, BTX, VOC, H2S, NH3, dust fallout. Samples are taken in a passive way. BTX, VOC and dust fallout sample taking period is 30 days and that of the others is 14 days. Radiello sample taking system is used. In addition to former pollutants a PM10 aerosol particle concentration is continually measured in the second zone and the reference point as well FH62IR beta dust meters are use for these determinations. Partial evaluation of a measurement carried out so far shows a seasonal dependency of results and a dependency of concentration field spatial distribution on monitoring station location and on its distance from significant potential pollutant sources. © SGEM2012 All Rights Reserved by the International Multidisciplinary Scientific GeoConference SGEM. Source


Burda J.,Brown Coal Research Institute | Burda J.,Charles University | Hartvich F.,Charles University | Hartvich F.,Czech Institute of Rock Structure And Mechanics | And 3 more authors.
Natural Hazards and Earth System Science | Year: 2013

The catastrophic landslide at Eisenberg in North Bohemia was reactivated during January 2011. This study integrates a range of geoscientific evidence in order to constrain the spatial and temporal development of this reactivation. It has investigated long-term geodetic measurements to assess the morphological development of the site over the last two decades. There is evidence to suggest that, over this period, the site had been subjected to progressive deformation caused by the collapse of an old mine gallery. However, climatic data show that the reactivation itself was triggered by a dramatic rise in the water table induced by rapid snowmelt during a period of winter warming. Furthermore, geomorphological mapping has been used to characterise the morphology of the reactivated landslide and geophysical profiling has been used to analyse its internal structure. The results show that fissures are continuing to develop above the reactivated landslide scarp while highly saturated stiff-fissured claystones provide an incipient slide plane. The application of laser scanning has shown minimal evidence for ongoing landslide activity. It is, however, clear that future landslide events will occur here due to the favourable lithological, structural, and geotechnical conditions. Finally, we propose that future landslide activity at the site may be predicted by the height of water table as this defines theoretical pore pressure at the depth of the shear plane. © 2013 Author(s). Source


Fecko P.,VSB - Technical University of Ostrava | Vales J.,Brown Coal Research Institute
28th Annual International Pittsburgh Coal Conference 2011, PCC 2011 | Year: 2011

The paper deals with research in new potential flotation agents for black coal and their comparison with an industrially applied flotation agent Montanol 508, which is used in the black coal preparation plants both in the Czech Republic and Poland. The potential flotation agents are a liquid organic phase from pyrolysis of brown coal disposed of pyrogenetic water (brown-coal tars). The experimental flotation tests are implemented using black coal samples from Darkov Mine in the CR. The effectiveness criterion of the work is to obtain flotation concentrate quality with ash content below 10 %. The results imply that it is possible to produce flotation agents from brown coal tars, which may come in useful in the flotation of black coal. Source


Hendrychova M.,Czech University of Life Sciences | Salek M.,Czech University of Life Sciences | Tajovsky K.,Academy of Sciences of the Czech Republic | Rehor M.,Brown Coal Research Institute
Restoration Ecology | Year: 2012

Variation in soil properties may influence diversity of invertebrate communities, a crucial component of every ecosystem, and their impact should be considered also in restoration management. Although most spoil heaps have been reclaimed after brown coal mining, some post-mining sites are left to natural succession. Little is known, however, about the effects of these two fundamentally different approaches on diversity of invertebrates inhabiting these stands. While controlling for habitat characteristics, we analyzed the effects of soil properties on species richness of seven invertebrate groups representing various trophic levels and diverse spatial niches at afforested spoil heaps and adjacent pits managed under these two basic restoration approaches in the North Bohemia Brown Coal Basin (Czech Republic, central Europe). Forty-seven percentage of 140 invertebrate species occurred on both reclamations and successions, but many were found exclusively on successions (37%) or reclamations (16%). The species richness of various groups was affected by different soil properties either independently of other variables or in interaction with microclimatic conditions or management history. These results imply a need for diverse management approaches in post-mining areas to support the diversity of invertebrate communities. Technical reclamations with artificial plantations and spontaneous forest development on bare substrate (thus creating mosaics of open patches and afforested stands with different soil deposit materials) were found to be reasonable alternatives to support invertebrate richness on post-mining forested stands. We conclude that these two approaches should properly be combined in practice. © 2011 Society for Ecological Restoration International. Source

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