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Rohana Chandrajith Nadeesha Koralegedara K. B. Ranawana H. J. Tobschall C. B. Dissanayake 《Environmental Geology》2009,57(1):17-28
Forest die back has been observed from 1980s in the montane moist forest of Horton Plains in the Central Sri Lanka for which
the aetiology appears to be uncertain. The concentration levels of Na, K, Ca, Mg, Fe, Mn, Cu, Ni, Zn and Pb in canopy leaves,
bark and roots, which were collected from dying and healthy plants of three different endemic species, Calophyllum walkeri, Syzygium rotundifolium and Cinnamomum ovalifolium, from three different die back sites were studied. Soils underlying the plants were also analyzed for their extractable trace
metals and total contents of major oxides. Analysis of dead and healthy plants does not show any remarkable differences in
the concentrations of studied trace elements. The results show that there is a low status of pollution based on the concentrations
of chemical elements of environmental concern. Extractable and total trace element analysis indicates a low content of Ca
in soils due to high soil acidity that probably leads to Mg and Al toxicity to certain plants. Relatively high Al levels in
the soil would affect the root system and hamper the uptake and transport of essential cations to the plant. It therefore
seems that the forest declining appears to be a natural phenomenon, which occurs due to the imbalance of macro and micronutrients
in the natural forest due to excessive weathering and the continuous leaching of essential elements. 相似文献
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