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Seasonal effects of lead uptake by snow vole Chionomys nivalis (Martins 1842) in West Tatra Mts.: bone metal concentrations and hematological indices

100%

Janiga M. , Hrehova Z. , Kostkova-Zelinova V.

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nr 3

EN

Since the mountains often represent a barrier for the pollutants in many regions, the concentrations of toxic elements in the tissues of alpine animals may remain relatively high and do not decrease in the current times. To estimate heavy metal contamination of alpine ecosystems Snow voles (Chionomys nivalis) are very useful monitors. They are small, easy to catch, have a territory of limited range, fairly short life span and they are closely adjusted to their environment The voles were monthly bait-trapped in the West Tatras, the Western Carpathians, Slovakia. The local population was studied at the Brestova mountain chain (49°13’29.43’’N; 19°40’46.07’’E, 1902 m.a.s.l.). The animals were trapped in September 2009 and from May to November 2010. The global sampling yielded a total of 50 samples (trapped and retrapped individuals). The lead concentrations in the tail vertebrae and the number of micronuclei in peripheral blood were examined. The Pb levels in voles were exceptionally high in overwintering mature animals (16.1 μg g–1dry weight in average) in comparison to young immatures (4.3 μg g–1). Females had significantly higher concentrations of Pb in their bones (13 μg g–1) than males (7.3 μg g–1). Snow vole adults caught in the spring exhibited significantly higher micronuclei frequencies in peripheral blood than immature ones trapped in summer or fall. Given that Pb is bioaccumulated in the diet of voles, this study showed that feeding on winter diet (mosses, lichens) could constitute a major pathway for the entry of Pb into food chain of alpine habitats. The usefulness of Snow voles as biomonitors of environmental contamination in alpine ecosystems was highly recognized.

2

Effect of organic substance with diversified decomposition degree on cadmium and lead uptake by lettuce [Lactuca sativa L.]

100%

Bosiacki M. , Tyksinski W.

Roczniki Akademii Rolniczej w Poznaniu. Ogrodnictwo

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2004

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tom 37

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A comparative study of lead uptake by three populations of the snail Helix aspersa Muller

100%

Richmond L. , Beeby A.

Polish Journal of Environmental Studies

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1992

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tom 01

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nr 1

EN

Pb uptake by three populations of the snail Helix aspersa was measured in a series of experiments supplying PbS04 in an agar diet. Uptake rates in snails from a site grossly polluted with Pb were lower than in the two other populations and were unafected by the initial body burdens of Pb. Populations of snails from a Pb-free site showed much greater variability in tissue Pb burdens and faster rates of accumulation than populations from the polluted site. Snails from a site with Pb concentrations between the other two sites showed intermediate rates of uptake. It is suggested that snails from the highly contaminated site have adapted to high environmental levels of Pb and that this adaptation is genetically based.

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Biological aspects of cadmium and lead uptake by Phragmites australis [Cav. Trin ex Steudel] in natural water ecosystems

70%

Kozlowska M. , Jozwiak A. , Szpakowska B. , Golinski P.

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nr 2

299-312

EN

In natural environment plants are exposed to many different stress factors, including heavy metals, whose elevated concentration causes oxidative stress, connected with formation of reactive oxygen species (ROS). Therefore, plants have developed defence systems, including enzymatic antioxidant system, able to remove ROS. The work concerns the accumulation of two heavy metals, cadmium (Cd) and lead (Pb), as well as the phenomenon of oxidative stress caused by increased concentration of these metals in common reed (Phragmites australis), a dominant species in the littoral zone of many water reservoirs. The plants were obtained from four water bodies situated in Poznan: Kierskie Lake, Rusałka Lake, Strzeszyńskie Lake and Sołacki Pond. The aim of the study was to examined the accumulation of heavy metals and the relation between activity of antioxidant enzymes in rhizome, stem and reed leaves during the vegetative period. Three antioxidant enzymes were analyzed: ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and superoxide dismutase (SOD). The statistical analysis was done to determine the influence of the heavy metals on the activity of the antioxidant enzymes, involved in limiting and removing results of oxidative stress. Heavy metals were accumulated in common reed in all the four water reservoirs, but the activity of enzymes was variable during the observation period. Statistical analyses suggest that there are some correlations among concentration of metals and the activity of antioxidative enzymes. However, the results do not provide an unambiguous determination of the effect of heavy metals on enzymatic activity. Summing up, the contamination of the water ecosystems caused by heavy metals was so low that it did not influence the activity of the analysed enzymes.

PL

W środowisku naturalnym rośliny są narażone na działanie metali ciężkich. Nadmierne ich stężenia w roślinach powodują stres oksydacyjny, wywoływany powstawaniem reaktywnych form tlenu (ROS). W celach obronnych organizmy roślinne wykształciły wiele systemów antyoksydacyjnych, w tym enzymatyczne umożliwiające usuwanie ROS. Praca dotyczy akumulacji dwóch metali ciężkich – kadmu (Cd) i ołowiu (Pb) oraz zjawiska stresu oksydacyjnego w roślinach powodowanego przez nadmierne stężenia jonów metali ciężkich w środowisku oraz w organach trzciny pospolitej (Phragmites australis) – gatunku występującego i dominującego w strefie litoralnej wielu zbiorników. Materiał roślinny pochodził z czterech zbiorników wodnych zlokalizowanych w obrębie miasta Poznania: Jeziora Kierskiego, jeziora Rusałka, Jeziora Strzeszyńskiego i Stawu Sołackiego. Celem badań było określenie zależności między zawartością metali ciężkich a aktywnością enzymów antyoksydacyjnych w kłączach, łodydze i liściach trzciny na przestrzeni okresu wegetacyjnego. Analizowano aktywność trzech enzymów antyoksydacyjnych: peroksydazy askorbinianowej (APX) i gwajakolowej (GPX) oraz dysmutazy ponadtlenkowej (SOD). Przeprowadzono analizy statystyczne celem określenia wpływu czynników stresu oksydacyjnego wywołanego przez metale ciężkie na aktywność enzymów antyoksydacyjnych, które są zaangażowane w ograniczanie i usuwanie skutków tego zjawiska. Metale ciężkie akumulowane w roślinach we wszystkich ocenianych zbiornikach wodnych wykazywały tendencję wzrostową, natomiast aktywność enzymów w roślinach była silnie zróżnicowana w całym okresie obserwacji. Analizy statystyczne sugerują wprawdzie istnienie pewnych korelacji między stężeniem metali w roślinach a aktywnością enzymów antyoksydacyjnych, jednakże nie pozwala to na jednoznaczne określenie wpływu badanych metali na zmienność w aktywności tych enzymów. Podsumowując, stwierdzone skażenie ekosystemów wodnych metalami ciężkimi było na tyle niskie, że nie wpływało modyfikująco na aktywność badanych enzymów.