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Kamila Widziewicz and Krzysztof Loska

). Azcue J.M.: Environmental significance of elevated natural levels of arsenic , Environmental Reviews, 3 , 212-221 (1995). Behari J.R, R. Prakash: Determination of total arsenic content in water by atomic absorption spectroscopy (AAS) using vapour generation assembly (VGA) , Chemosphere, 63 , 17-21 (2006). Bissen M., Frimmel F.H.: Arsenic - a Review. Part I: Occurrence, Toxicity, Speciation, Mobility , Acta Hydrochimica Hydrobiologica, 31 , 9-18 (2003). Bodzek M., K. Konieczny

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Pavel Anatolyevich Nikolaychuk

Abstract

Thermodynamic properties of lead species in aqueous solution are collected. The chemical equilibria between various forms of Pb(II) are considered. The speciation diagrams for the equilibria 4[PbOH]+(aq) ⇄ [Pb4(OH)4]4+(aq) and 2[Pb3(OH)4]2+(aq) ⇄ [Pb6(OH)8]4+(aq), and the thermodynamic activity - pH diagram of Pb(II) species are plotted. Basic chemical and electrochemical equilibria for lead are calculated. The potential - pH diagram for Pb - H2O system is revised.

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Paschal Okiroro Iniaghe and Gilbert Umaye Adie

, Index of geoaccumulation in the sediments of the Rhine River, Geojournal 2 (1969) 108-118. [20]. A. Tessier, P.G.C. Campbell, M. Bisson, Sequential extraction procedure for the speciation of particulate trace metals, Anal. Chem. 51 (1979) 844-851. [21]. C.M.A. Iwegbue, G.E. Nwajei, O.I. Eguavoen, Impact of land-use patterns on chemical properties of trace elements in soils of rural, semi-urban and urban zones of the Niger Delta, Nigeria, Soil & Sed. Contam. 21 (2012) 19-30. [22]. S. Kabiru, R. Yakubu, A. Lukman, T

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Aravinda Ravibhanu Sumanarathna, Buddhika Madurapperuma, Janaka Kuruppuarachchi, Jinadasa Katupotha, S.M.K. Abeywardhana and Pathmakumara Jayasinghe

Abstract

A sufficient knowledge on prehistoric culture and habitat of earliest Homo sapiens (Balangoda man) is available in Batadomba-lena cave, a noticeable rock shelter in lowland rainforest of southwestern Sri Lanka goes upto Pleistocene and Holocene eras. Late Pleistocene inhabitants of Batadombalena cave’s foraged for a broad spectrum of plant and mainly arboreal animal resources such as, monkeys, squirrels and rainforest snails etc. Archaeo-faunal evidence would help to describe the prehistoric man eating behavior as well as availability of nature pre-historic flora, fauna and environmental status. The family Acavidae is very sensitive to climatic variations, hence used as a bio-indicator to describe the variations of paleo-climatic nature. This study examined the morphological features of 20 samples of Acavidae family (living/fossil samples of Acavus superbus, and sub fossil samples of Oligospira waltoni) collected from soils by digger method in 2005 and compared with 20 samples from the same area at presently available. The shell characters of snails such as, height, width, diameter of mouth, thickness of lip, and angular of axis were measured and subjected to multivariate analysis to understand how climatic variability and nature of paleo-diet contribute survival of Acavidae species. Results showed that Acavus superbus living species had large shell characteristics than the sub fossils. Results of similar study in the same climatic status in 2000 showed that the shell measurements of Acavus superbus are relatively larger than both living and sub fossils in Batadobalena cave. Ordination diagram derived from species shell characteristics showed that Acavus superbus living species grouped as scattered /diffuse clusters, while sub fossil species grouped as a single cluster at the center of the ordination diagram. It is imply a trend of speciation /diversification of Acavus species from Pleistocene era to date. Multivariate analyses prove that, a strong positive correlation of species characteristics, such as height (r = 0.62), thickness of lip (r = 0.544) and angular of axis (r = 0.744), and a strong negative relationship (r = 0.832) for shell width for the species were observed. Our results are useful to compare with other fossil snails to see whether the climate change influence for changing body size. In conclusion, palaeo-environment, and present environment variation has been occurred in minimum way without much changes to observed Acavidae species compositions present and past.

Open access

Jana Dadová, Jiří Kupka, Peter Barto, Erika Remešicová and Tomáš Štrba

Abstract

The present study investigates mercury contamination of soil, groundwater, surface water, vegetation and food commodities (fruit, vegetable, mushroom, and fish) close to the abandoned Hg deposit in Malachov, Central Slovakia. The soil was classified as cambi-soil (rendzina). Maximum concentrations of Hg (44.24 ppm) were found in the soil from the area nearby old mining activities in the Veľká Studňa locality. In the groundwater, 0.84 μg.L-1, and in the surface water, even 394 μg.L-1 of Hg content was found. Also plant tissues and mushrooms are Hg-contaminated (in the root of Salix fragilis, the Hg content was 22 mg.kg-1). The Hg concentration decreases in general in the following order: root, branch/stem, and leaf/needle. In the food commodities, the Hg content does not exceed the Slovak law limits. The Hg content in trout muscle (from the local Malachovský brook) is 252 μg.kg-1 and in liver 402 μg.kg-1.

The calculation of an AMD formation potential (neutralisation potential, total acidity production, net neutralisation potential) is discussed as well. The value of the total acidity production potential (sensu Sobek et al., 1978) is low (1.562 - 3.125; with exception of a single sample, in which it increased to 9.375). On the other hand, the abundant presence of dolomite rocks causes a high neutralization potential value (up to 812.84). This result suggests that the assumption of the AMD production is excluded and the environmental risk from this viewpoint might be neglected

Open access

Iwona Makuch

Abstract

In order to determine the influence of intensive horticulture on the amount of lead and its fraction contents, there were selected soil profiles from following objects to be researched: house gardens and allotment gardens from town areas and arable field on the outskirts of the town. It has not been determined that there is any influence of manner usage on total lead content as well as its distribution in soil profiles. The fractionation composition has created the following series: fraction IV > fraction III > fraction II > fraction I. The manner of usage has influenced the content and distribution the III fraction of lead connected with organic matter. Humus horizons of garden soils is characterized as the highest in its content.

Open access

M. Wojnicki and A. Podborska

Abstract

The kinetics studies of redox reaction between palladium(II) chloride complex ions and potassium formate in acidic aqueous solutions was investigated. It was shown, that the reduction reaction of Pd(II) is selective in respect to Pd(II) complex structure. The kinetic of the process was monitored spectrophotometrically. The influence of chloride ions concentration, Pd(II) initial concentration, reductant concentration, ionic strength as well as the temperature were investigated in respect to the process dynamics. Arrhenius equation parameters were determined and are equal to 65.8 kJ/mol, and A = 1.12×1011 s−1.

Open access

Marianna Czaplicka and Halina Pyta

synthetic fl ue gas, Fuel Processing Technology, 63, pp. 93-107. Bełdowska, M., Saniewska, D., Falkowska, L. & Lewandowska, A. (2012). Mercury in particulate matter over Polish zone of the southern Baltic Sea, Atmospheric Environment, 46, pp. 397-404. Bhardwaj, R., Chen, X. & Vidic, R.D. (2009). Impact of fl y ash composition on mercury speciation in simulated fl ue gas, Journal of the Air & Waste Management Association, 59(11), pp. 1331-1338. Bojakowska, I. & Sokołowska, G. (2001). Mercury in mineral raw materials exploited

Open access

János Oláh

., MAJECKA K., MAJECKI J., SZCZESNY B., URBANIC G. & VALLE M. 2015: Limnephilid taxa revised by speciation traits: Rhadicoleptus, Isogamus, Melampophylax genera, Chaetopteryx rugulosa, Psilopteryx psorosa species groups, Drusus bolivari, Annitella kosciuszkii species complexes (Trichoptera, Limnephilidae). Opuscula Zoologica (Budapest) 46(1) : 3–117.

Open access

Guţu Claudia Maria, Bălălău D, Ilie Mihaela, Purdel Carmen Nicoleta and Gubandru Miriana

References 1. Henke KR. Arsenic: Environmental Chemistry, Health Threats and Waste Treatment. John Wiley & Sons, University of Kentucky, USA, 2009, 146-161. 2. Bissen M, Frimmel FH: Arsenic - a Review. Part I: Occurrence, toxicity, speciation, mobility. Acta Hydrochimica et Hydrobiologica. 2003;31:9-18. 3. U.S. EPA, National Primary Drinking Water Regulation. Arsenic and Clarifi cations to Compliance and New Source Contaminants Monitoring. Fed. Reg. 2001;66:6976-7066. 4. Yan-Chu H. Arsenic in