Tomas Navratil

Tomas Navratil
The Czech Academy of Sciences | AVCR · Institute of Geology

PhD. Charles University Prague
I am intrigued by interaction of trees and plants with atmospheric gaseous mercury and all the consequences...

About

81
Publications
40,236
Reads
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1,434
Citations
Citations since 2017
25 Research Items
822 Citations
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2017201820192020202120222023050100150
2017201820192020202120222023050100150
2017201820192020202120222023050100150
Introduction
The contamination of environment with toxic mercury has been a center point of my current research. On one side my research is focused on a long-term monitoring of small background forest catchment and of a polluted river and floodplain. On the other side I have been dealing with interactions of atmospheric Hg with plants (trees) - usage of tree rings as an archive for reconstruction of atmospheric Hg levels.
Additional affiliations
October 2007 - June 2008
University of Maine
Position
  • Fulbright Fellow
September 2006 - present
Charles University in Prague
Position
  • Heavy Metals in the Environment
January 2001 - December 2012
Czech Geological Survey
Position
  • Researcher

Publications

Publications (81)
Article
We propose tree rings of European Larch (Larix decidua) as a widely available and reliable geochemical archive of local and regional changes in atmospheric mercury (Hg). Mean Hg concentrations in larch tree rings from 8 background sites across the Czech Republic ranged from 2.2 to 4.8 µg kg-1; the maximum concentrations occurred in the period 1951-...
Article
We evaluated a 14-year trend (2003-2017) in mercury (Hg) concentrations and fluxes in six litterfall categories (needles, bark, twigs, cones, lichen, and a mixture of unidentified fragments) at six research plots situated in two central European unmanaged mountain forest stands, dominated by mature Norway spruce. One of the stands (catchment of Ple...
Article
From 2011 to 2019, mercury (Hg) stores and fluxes were studied in the small forested catchment Lesní potok (LES) in the central Czech Republic using the watershed mass balance approach together with internal measurements. Mean input fluxes of Hg via open bulk deposition, beech throughfall and spruce throughfall during the period were 2.9, 3.9 and 7...
Article
The Chemical Factory in Marktredwitz (CFM) is known as the oldest chemical factory in Germany (1778–1985), and from the beginning of the 20th century focused primarily on the production of mercury (Hg) compounds. Due to extensive pollution, together with employee health issues, the CFM was shut in 1985 by a government order and remediation works pr...
Article
Full-text available
Cadmium, Mn, and Zn are mobilised by plants commonly growing in floodplains, most notably willows (Salix) and alder (Alnus). These plants accumulate unwanted elements (Cd) or excessive element concentrations (Mn, Zn) in their foliage, thus introducing them into the food web and enriching them in floodplain surface by litterfall. In floodplain of th...
Article
Full-text available
Our study addressed mercury contamination hotspots that originated from Chemical Factory Marktredwitz, Germany. The factory was abandoned in 1985 but its legacy has been persistently endangering the river ecosystem of the Ohře River, a Labe (Elbe) River tributary in the Czech Republic. We identified the timing for the peak contamination of fine sed...
Article
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Trees predominantly take up mercury (Hg) from the atmosphere via stomatal assimilation of gaseous elemental Hg (GEM). Hg is oxidised in leaves/needles and transported to other tree anatomy including bole wood, where it can be stored long-term. Using Hg associated with growth rings facilitates archiving of historical GEM concentrations. Nonetheless,...
Preprint
Full-text available
Trees predominantly take up mercury (Hg) from the atmosphere via stomatal assimilation of gaseous elemental Hg (GEM). Hg is oxidised in leaves/needles and transported to other tree anatomy including bole wood where it can be stored long-term. Using Hg associated with growth rings facilitates archiving of historical GEM concentrations. Nonetheless,...
Article
Full-text available
Willows, woody plants of genus Salix common in floodplains of temperate regions, act as plant pumps and translocate the Cd and Zn in the soil profiles of uncontaminated and weakly contaminated floodplains from the sediment bulk to the top strata. We suggest this process occurs because the Cd and Zn concentrations in willow leaves exceed those in th...
Article
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Global chronic nitrogen (N) deposition to forests can alleviate ecosystem N limitation, with potentially wide ranging consequences for biodiversity, carbon sequestration, soil and surface water quality, and greenhouse gas emissions. However, the ability to predict these consequences requires improved quantification of hard-to-measure N fluxes, part...
Article
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In 1994, a network of small catchments (GEOMON) was established in the Czech Republic to determine input – output element fluxes in semi‐natural forest ecosystems recovering from anthropogenic acidification. The network consists from 16 catchments and the primary observations of elements fluxes were complemented by monitoring of biomass stock, elem...
Article
The fate of atmospherically deposited mercury (Hg) was studied in forest soils situated near various Hg anthropogenic emission sources, including chlor-alkali plants, cement production, and pig iron and steel factories in the Czech Republic. Some of these emission sources were more active in the past, while others continue operation with lowered du...
Article
Tree ring records are increasingly being used as a geochemical archive of past atmospheric mercury (Hg) pollution. However, it is not clear whether all tree species can be used reliably for this purpose. We compared tree-ring Hg records of two coniferous species-widely used Scots pine (Pinus sylvestris) and less frequently used European larch (Lari...
Article
Full-text available
Mercury is a ubiquitous environmental pollutant of dominantly anthropogenic origin. A critical concern for human health is the introduction of mercury to the food chain; therefore, monitoring of mercury levels in agricultural soil is essential. Unfortunately, the total mercury content is not sufficiently informative as mercury can be present in dif...
Article
Full-text available
This study aimed to evaluate the relevance of the floodplain pollution sinks of the legacy mercury (Hg) hot spot in Kössein–Röslau river system (east Bavaria, Germany) for further mobilisation and fluvial transport of mercury in suspended particulate matter (SPM), as an important transport medium of Hg in aquatic systems. The channel belt fluvial e...
Article
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The Brdy Highlands Protected Landscape Area (PLA) represents the youngest area of this category of nature protection in the Czech Republic. It exists since January 1st, 2016, and a major part of it served as a military training ground in the period 1926–2015. The surroundings of the Brdy Highlands PLA are known for their industrial history (iron or...
Article
We evaluated changes in the concentration of cations, anions, nutrients (dissolved organic carbon, DOC; phosphorus, P; and nitrogen forms including nitrate, NO3− and total organic nitrogen, TON), and chlorophyll a (Chl-a) in 31 Tatra Mountain lakes in Slovakia and Poland during their recovery from acidic deposition (1992–2018). Typical effects of d...
Conference Paper
Full-text available
Evenkia is a district in Krasnoyarsk Krai, Russia, characteristic of preserved areas of East Siberian continental taiga. In 1908, this region experienced catastrophe (Tunguska event = TE). Over 2,000 km2 of boreal forest were felled and burned. The exact cause of this event is not known but this event has often been associated with either an astero...
Article
Full-text available
The concentration of Hg and Pb pollutants was examined in sediments of a central European lowland river, the Ohře River. The pollution originated from several sources that were active mainly between the thirteenth and twentieth centuries. Its passage through the river system has been altered by two dam reservoirs built in the 1960s. The pre-dam pol...
Article
Full-text available
The Brdy Protected Landscape Area is built of geologically heterogeneous units with numerous rock types which locally show signs of hydrothermal alterations. This study was carried out as an additional investigation to the mapping of local forest humic soils contaminated by Hg. Results of the survey did not exactly correspond to the so far known hi...
Article
Archived soil samples can provide important information on the history of environmental contamination and by comparison with recently collected samples, temporal trends can be inferred. Little previous work has addressed whether mercury (Hg) concentrations in soil samples are stable with long-term storage under standard laboratory conditions. In th...
Article
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Purpose The Ohře River has received contamination from metal mining and metallurgy (mainly Cu, Pb, Sn, U, Zn) over the previous five centuries. This contamination history has been poorly documented. Contamination has entered the river system in its middle reach, where the channel is incised and bedrock confined, which impedes overbank deposition. O...
Article
We assessed > 100 years of mercury (Hg) pollution recorded in the tree rings of Scots Pine near a Czech chlor-alkali plant operating since 1941. Hg concentrations in tree rings increased with the launching of plant operations and decreased when Hg emissions decreased in 1975 due to an upgrade in production technology. Similar to traditional bioindi...
Article
Full-text available
Changes in atmospheric deposition, stream water chemistry, and solute fluxes were assessed across 15 small forested catchments. Dramatic changes in atmospheric deposition have occurred over the last three decades, including a 70% reduction in sulphur (S) deposition. These changes in atmospheric inputs have been associated with expected changes in l...
Article
Forests play a primary role in the cycling and storage of mercury (Hg) in terrestrial ecosystems. This study aimed to assess differences in Hg cycling and storage resulting from different vegetation at two adjacent forest stands - beech and spruce. The study site Načetín in the Czech Republic's Black Triangle received high atmospheric loadings of H...
Article
The Journal regrets that the author's names were tagged incorrectly resulting in author forenames appearing as surnames. The correct author names are: Filip Oulehle, Jiří Kopáček, Tomáš Chuman, Vladimír Černohous, Iva Hůnová, Jakub Hruška, Pavel Krám, Zora Lachmanová, Tomáš Navrátil, Petr Štěpánek, Miroslav Tesař, Christopher D. Evans. The Journal...
Article
Data from 32 long-term (1994–2012) monitoring sites were used to assess temporal development and spatial variability of sulphur (S) and inorganic nitrogen (N) concentrations in bulk precipitation, and S in throughfall, for the Czech Republic. Despite large variance in absolute S and N concentration/deposition among sites, temporal coherence using s...
Article
Atmospheric phenomena have a large influence on the flux of mercury (Hg) and lead (Pb) to terrestrial and aquatic ecosystems. Some direct phenomena involve high-frequency variations in air movement; other indirect processes involve longer-term changes in climate and associated vegetation and hydrology. Here, we use evidence from sediment cores to e...
Article
Symmetrical cavities of spherical, ellipsoidal or subtriangular shapes, tens of centimetres to 2–3 m in diameter, have been documented in a number of European sandstone districts extending between Luxembourg and Poland. Although previously thought to be synonymous with true tafoni by some authors, the studied symmetrical cavities share specific fea...
Article
Cell wall envelopes treated with sodium hydroxide and spray-dried were used as mercury sorbents. The sorbent having sorption capacity 17.7 ± 0.1 μmol/g determined was employed for preconcentration of mercury containing 1-10 ng/L. After preconcentration, bioavailable mercury was detected in samples of soil, stream, and tap water via induction of bio...
Conference Paper
Full-text available
Iceland is an active source of dust originating from glaciogenic and volcanic sediments. The frequency of days with dust suspension exceeded 34 dust days annually in 1949-2011. About 4.5 million tons of dust is annually distributed over local Icelandic glaciers, but dust is likely deposited on the Arctic glaciers as well. Dust events in NE Iceland...
Article
Iceland is an active dust source in the high-latitude cold region. About 50% of the annual dust events in the southern part of Iceland take place at sub-zero temperatures or in winter, when dust may be mixed with snow. We investigated one winter dust event that occurred in March 2013. It resulted in a several mm thick dark layer of dust deposited o...
Article
Methods commonly used for soil sample preparation may be unsuitable for measuring Hg concentrations due to the possible loss of volatile Hg species when drying at higher temperatures. Here, the effects of freeze-drying, air drying at 25°C and oven-drying at 105°C on Hg concentrations in two soil types and three standard reference materials were tes...
Article
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The petrography and mineral chemistry of the coarse-grained, weakly porphyritic (muscovite-) biotite Říčany granite (Variscan Central Bohemian Plutonic Complex, Bohemian Massif) were studied in order to assess the distribution of major and trace elements among its minerals, with consequences for granite petrogenesis and availability of geochemical...
Article
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Parts of the Czech Republic received extreme loading of acid deposition from coal combustion in the second half of the 20th century. Although associated Hg deposition was not directly measured, Hg deposition rates calculated from peat cores approach 100 µg m-2 yr-1. We quantified the soil concentrations and pools of Hg with carbon (C), sulfur (S) a...
Article
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We measured a dust event which occurred during wet and low wind/windless conditions as the result of surface heating in August 2013. Maximum particle number concentration (PMtextasciitilde0.3-10 μm) reached 149,954 particles cm -3 min-1 while mass concentration (PMtextless10 μm) was 1757 μg m -3 min -1. The suspended dust was very fine with the hig...
Article
Full-text available
Abstract. The paper deals with the recent and present-day natural components of the dust inputs to sediments, and aims to attract the attention of geologists to atmospherically mediated teleconnections among basins across the globe. Similar components as today can also be expected to exist in the pre-human history of the Earth, with capability to a...
Article
Full-text available
Particles originating from the last major Eyjafjallajökull volcano eruption in April 2010 were subsequently found in settled dust samples collected in a suburban area of Prague, Czech Republic. These dust samples contained predominantly non-volcanic particulate matter of super-regional but mainly local origin. The highest proportion of the Eyjafjal...
Article
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The area of the Black Triangle has been exposed to extreme levels of acid deposition in the twentieth century. The chemical weathering of sandstones found within the Black Triangle became well-known phenomenon. Infiltration of acid rain solutions into the sandstone represents the main input of salt components into the sandstone. The infiltrated sol...
Article
Full-text available
The protected area “Bohemian Switzerland National Park” with its characteristic sandstone landscape was influenced by the long-term air pollution and acidic deposition within the area known as Black Triangle (located where Germany, Poland, and the Czech Republic meet, is one of the Europe’s most polluted areas). The local Upper Cretaceous sandstone...
Article
Full-text available
The lead (Pb) content and (206)Pb/(207)Pb ratio were studied in three peat profiles dated by (210)Pb from the border-area mountains of the Czech Republic and in the tree rings of spruce trees located in their immediate vicinity. Both archives document a similar progress in Pb pollution levels and Pb accumulation in the 1950's-1990's. The deposition...
Article
Full-text available
The annual output of filtered mercury (Hg) from Lesni potok catchment, a forested ecosystem in central Europe, was estimated at 0.87 μg m⁻². More than 70% of the annual mercury output flux occurred during the spring snowmelt period. The snowmelt period is the most important part of the hydrological year in central European forested ecosystems. Aver...
Article
Full-text available
Metal mining and processing in the central Czech Republic has led to the contamination of surrounding soils and vegetation. In this study, Hg concentrations were measured in spruce (Picea abies L.) and beech (Fagus sylvatica L.) tree rings to monitor historical Hg deposition in the area. The highest Hg concentrations were found in spruce at an HgS...
Article
Full-text available
The Bear Brook Watershed in Maine (BBWM), USA is a paired watershed study with chemical manipulation of one watershed (West Bear = WB) while the other watershed (East Bear = EB) serves as a reference. Characterization of hydrology and chemical fluxes occurred in 1987-1989 and demonstrated the similarity of the ca. 10 ha adjacent forested watersheds...
Article
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Mean annual concentration of SO4(-2) in wet-only deposition has decreased between 1988 and 2006 at the paired watershed study at Bear Brook Watershed in Maine, USA (BBWM) due to substantially decreased emissions of SO(2). Emissions of NO(x) have not changed substantially, but deposition has declined slightly at BBWM. Base cations, NH4+, and Cl(-) c...
Article
Full-text available
A comparison of rare earth elements' (REE) atmospheric signatures in various ecosystem compartments was carried out in the vicinity of the Lesni potok catchment (LP), Czech Republic. REE signatures were investigated from 2004 to 2006 in rainwater, throughfall, tree foliage (Picea abies, Fagus sylvatica) and lichens (Hypogymnia physodes) for selecte...
Article
Full-text available
The paper deals with the recent and present-day natural components of the dust inputs to sediments, and aims to attract the attention of geologists to atmospherically mediated teleconnections among basins across the globe. Similar components as today can also be expected to exist in the pre-human history of the Earth, with capability to affect the...
Article
Full-text available
The Litavka River (length 56km, watershed area 630km2, average flow at the outlet to the Berounka River 2.57m3 s−1) drains the historical mining, ore processing, and smelting region of Příbram. This Ag–Pb–Zn±Sb ore district (production from the thirteenth century to 1978, locally to 1980) is known for extensive heavy metal contamination. Recent con...
Article
Full-text available
Vertical distribution and mercury speciation in soil profiles were studied to evaluate the extent of contamination and potential Hg mobility in a historical Hg mining area. Three sites were chosen for a case study of Hg contamination. One site was considered a low impact site located 400m uphill from the mining activities and two sites were located...
Article
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In year 2006, 17.9 ha of forest was burned during a forest fire at the Bohemian Switzerland National Park found in northern part of Czech Republic (CR), central Europe. Complete combustion of organic soil (4,039 t) on the burned area caused volatilization of 1.34 +/- 0.07 kg of Hg. Thus Hg emissions due to fire amounted to 75.1 g ha(-1). The averag...
Article
Full-text available
Fine-grained floodplain sediments of the catastrophic 2002 flood deposited along the lower reaches of the Berounka and Vltava Rivers, Czech Republic, were not highly contaminated with heavy metals and other toxic elements. This is due to the dominantly mineral character of the sediments (Ctot in the range 3.97–5.01%, relatively low content of clay...
Article
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Mercury (Hg) concentration profiles and historical accumulation rates were determined in three 210Pb-dated cores from a peat deposit in the vicinity of a lead (Pb) smelter at Příbram, Czech Republic. The Hg concentrations in peat samples ranged from 66 to 701 μg kg−1. Cumulative Hg inventories from each core (for the past ∼150 yr) varied by a facto...
Article
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We experimentally determined the adsorption characteristics of natural, freshly precipitated Al(OH)3 for SO4 and PO4. The fresh Al precipitate occurred in stream sediment of Jachymov Stream (Czech Republic). The Al-rich sediment strongly adsorbed added PO4 prior to acidification experiment; this sorbed PO4 was released only after substantial dissol...
Article
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Stream nitrogen (N) export and nitrate \((\text {NO}^-_3) \) concentration were measured at 14 forested watersheds (GEOMON network) in the Czech Republic between 1994 and 2005. In the last several decades, emissions of sulfur (S) and N compounds have decreased throughout much of Europe. In the Czech Republic, atmospheric deposition of S has decreas...
Article
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Mine waste dumps of historic mercury mines represent environmental threat. In the central Czech Republic, Hg ores were mined at two sites for more than 150 years. Mine wastes collected from dumps near Hg mines were elevated in total Hg (up to 120 microg(-1)). Thermal-desorption method revealed that most of Hg (>80%) in studied waste material was pr...
Article
Full-text available
Mn biogeochemistry was studied from 1994 to 2003 in a small forested catchment in the central Czech Republic using the watershed mass balance approach together with measurements of internal stores and fluxes. Mn inputs in bulk deposition were relatively constant during a period of sharply decreasing acidic deposition, suggesting that the Mn source...