Cesium-137 contamination of oak (Quercus petrae Liebl.) from sub-mediterranean zone in South Bulgaria
| Autor: | Miglena Zhiyanski, Viktor Badulin, Jaume Bech, A. Clouvas, Ilia Penev, Maria Sokolovska |
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| Rok vydání: | 2010 |
| Předmět: |
Mediterranean climate
Health Toxicology and Mutagenesis Poaceae Quercus Botany Environmental Chemistry Bulgaria Waste Management and Disposal Ecosystem Biomass (ecology) biology General Medicine Vegetation Contamination biology.organism_classification Pollution Fagaceae Agronomy Cesium Radioisotopes Caesium-137 visual_art visual_art.visual_art_medium Environmental science Bark Quercus petraea Environmental Monitoring |
| Zdroj: | Journal of environmental radioactivity. 101(10) |
| ISSN: | 1879-1700 |
| Popis: | This study focuses on the cesium-137 (137Cs) contamination in grass and in different compartments of oak trees growing in ecosystems, located in the zone with sub-mediterranean climate in South Bulgaria, characterized with high summer temperatures, low precipitation and often periods of drought. In 2008, three experimental sites – PP1, PP2, PP3 – were sampled in oak ecosystems from Maleshevska Mountain at 900 m above sea level. Samples from grass species and oak tree leaves, branches with different diameter, wood disks and bark were analyzed for 137Cs activity with γ-spectrometry. The soil-to-plant transfer factor (TF) values for 137Cs were estimated differentiating different tree compartments. Our findings showed relatively high activity concentrations of 137Cs in oak trees even 22 years after the Chernobyl accident. The grass under oak was less contaminated compared with the oak trees. The different organs of oak trees could be distinguished according to the 137Cs contamination as follows: bark > branches (d leaves > branches (d > 3 cm) > wood. The relatively higher contamination of bark compared with the new-formed biomass suggested that a significant part of 137Cs was accumulated as a result of direct adsorption at the time of the main contamination event. The TF values obtained and the presence of 137Cs in the branches, leaves and in the wood formed after 1986 confirmed that 22 years after the contamination, the main mechanism of 137Cs entrance in tree biomass was the root uptake. |
| Databáze: | OpenAIRE |
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