Soil impact and radiation dose to native plants in forest ecosystem

Abstract

A radiation dose assessment model was applied to determine naturally occurring radionuclides ²³⁸U, ²¹⁰Po and ²³²Th in trees like Elaeocarpus oblongus, Evodia roxburghiana (Juice of the leaves that are used to treat fever), Vaccinium neilgherrense, Viburnum hebanthum and Michelia nilagirica and shrubs like Lasianthus coffeoiaes and Hedyotis stylosa in the agroforests of the Western Ghats, India and these areas were used for different agroforestry models of land development systems. The concentration of radionuclides in the biota and corresponding soil was measured using a gamma ray spectrometer and an alpha counter. The concentration ratios of these radionuclides varied substantially between the species, and E. oblongus showed a preferential uptake of all the radionuclides and hence useful for bio-indication of radionuclides in such soils. ERICA assessment tool was employed to provide an assessment of the potential doses to biota’s growing in agro forest E. oblongus appears to be much prone to radiation absorption from the dose risk point of view. The annual effective dose (AED) due to ingestion of these radionuclides in E. roxburghiana was also estimated, and was found to be lower than the world average.