Ričardas Taraškevičius

Ričardas Taraškevičius


Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 September 2022 in Plants
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Journal Article
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VVVaida Vaičiulytė
Vaida Vaičiulytė
Kristina LožienėKristina Ložienė
Kristina Ložienė
Ričardas TaraškevičiusRičardas Taraškevičius
Ričardas Taraškevičius
Intraspecific chemical polymorphism is characteristic of essential oil bearing Thymus pulegioides (Lamiaceae). Soil chemical composition and climatic conditions can influence not only quantitative and qualitative composition of essential oils, but also on prevalence of different chemotypes in space. The purpose of study was to determine the impact of edaphic and climatic factors on T. pulegioides essential oil composition and potential chemotypes prevalence. It were investigated 131 habitats of T. pulegioides in all ten climatic sub-districts of Lithuania. Essential oils were isolated by hydrodistillation and analysed by GC-FID and GC-MS. The content of humus was estimated by oxidation method, the content of mobile potassium (K2O) and mobile phosphorus (P2O5)—flame photometry using 0.2 M HCl solution, the soil pH—electrometrically and 15 elements of soil—by energy-dispersive X-ray fluorescence. The meteorological data (temperature, rainfall, photosynthetically active solar radiation and sunshine duration) were obtained from the meteorological bulletins. Results showed that humus in soil positively, manganese and cobalt—negatively influenced on the essential oil accumulation in T. pulegioides. Carvacrol was the most common compound in the essential oil of T. pulegioides; higher amounts of sulphur and mobile phosphorus, lower amounts of sodium in soil, higher rainfall in blooming period are favourable for this compound and for potential prevalence of carvacrol chemotype. Geraniol was frequent in the eastern and the central part of Lithuania, where the temperature in vegetation season is higher, and in soils characterised by higher and lower amounts of sodium and chlorine, respectively. Thymol, linalool and α-terpinyl acetate were rare. Edaphic and climatic conditions can differently influence on essential oil yield and chemical composition of species as well as on potential prevalence of different chemotypes of same species in space.

23 May 2017 in Environmental Geochemistry and Health
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Ričardas TaraškevičiusRičardas Taraškevičius
Ričardas Taraškevičius
RZRimantė Zinkutė
Rimantė Zinkutė
Laura GedminienėLaura Gedminienė
Laura Gedminienė
ŽSŽilvinas Stankevičius
Žilvinas Stankevičius

1 December 2017 in Journal of Geochemical Exploration
Verified
Journal Article
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Ričardas TaraškevičiusRičardas Taraškevičius
Ričardas Taraškevičius
JMJurga Motiejūnaitė
Jurga Motiejūnaitė
RZRimantė Zinkutė
Rimantė Zinkutė
AEAgnė Eigminienė
Agnė Eigminienė
Laura GedminienėLaura Gedminienė
Laura Gedminienė
ŽSŽilvinas Stankevičius
Žilvinas Stankevičius

5 September 2018 in Chemosphere
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Journal Article
Closed access
MJMarius Jasiulionis
Marius Jasiulionis
Linas BalčiauskasLinas Balčiauskas
Linas Balčiauskas
Laima BalčiauskienėLaima Balčiauskienė
Laima Balčiauskienė
Ričardas TaraškevičiusRičardas Taraškevičius
Ričardas Taraškevičius

10 August 2022 in Minerals
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Journal Article
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Eglė ŠatavičėEglė Šatavičė
Eglė Šatavičė
Grazina SkridlaiteGrazina Skridlaite
Grazina Skridlaite
IGInga Grigoraviciute
Inga Grigoraviciute
Aivaras KareivaAivaras Kareiva
Aivaras Kareiva
ASAušra Selskienė
Aušra Selskienė
Ričardas TaraškevičiusRičardas Taraškevičius
Ričardas Taraškevičius
A geochemical and mineralogical approach was used to analyze 3rd millennium BCE pottery from Southeast Lithuania that is attributed to the foreign Corded Ware Culture and local hunter-gatherers. SEM-EDS, XRF, XRD, and FTIR were used to study the peculiarities of the pottery and to develop hypotheses about the raw material and technology choices present. The amounts of ten major elements in the bulk and clay matrix compositions (XRF, SEM-EDS) and eleven trace analytes in the bulk compositions (XRF) were compared with the Clarke values and tested to highlight the significance (Mann–Whitney U and Wilcoxon Matched Pairs Tests) of the differences in the elemental quantities between the clay matrix and bulk compositions, and between the lighter and darker clay matrixes. These also revealed the advantage of Ward’s clustering method using the City-block distance of bulk compositions as a tool for inter-correlating ceramics in attributing them to specific communities and locations. The XRD, FTIR, and SEM-EDS mineralogical analyses indicated a predominance of iron-rich illite clay, quartz, and alkali feldspar, in addition to very low to medium firing temperatures. All of the pottery samples consisted of hydromicaceous clay from local Quaternary glacial sediments that contain weathered granitoid fragments.

22 December 2014 in Journal of Environmental Engineering and Landscape Management
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Journal Article
Closed access
RZRimantė ZINKUTĖ
Rimantė ZINKUTĖ
VBValentinas Baltrūnas
Valentinas Baltrūnas
Ričardas TaraškevičiusRičardas Taraškevičius
Ričardas Taraškevičius
BKBronislavas Karmaza
Bronislavas Karmaza
RSRimutė STAKĖNIENĖ
Rimutė STAKĖNIENĖ
DKDalia Kisielienė
Dalia Kisielienė
Geochemical investigations were conducted on Quaternary interglacial sediments in order to reveal if they can be a natural source of 10 potentially harmful chemical elements: As, Ba, Cr, Cu, Mn, Mo, Ni, Pb, V and Zn. Determination of the total contents of elements in 680 samples was performed by EDXRF analysis. The content of Ni, Cu, Pb, Ba in all analyzed samples was lower than maximum permissible concentrations (MPC) for soil, the content of Zn, V, Cr, Mn exceeded MPC values only in several samples (≤4%). The highest percentage of anomalous samples where MPC was exceeded was characteristic of Mo (21%) and As (12.6%). Therefore, interglacial sediments, especially enriched in organic matter and other sorbents, comprise one of the possible natural sources of Mo and As. It is probable that they contribute to As and Mo anomalies in stream sediments in Lithuania.