Comparative measurements of plant radioactivity in the Agrobotanical Garden and experimental fields

Abstract

In order to demonstrate the usefulness of the Garden's Catalogue in unforeseen situations, the radioactivity of some plant species cultivated on different plots of the Agrobotanical Garden has been measured in May 1986. Comparative measurements have been carried out on species harvested from the experimental fields Sapca-Verde (Cluj-Napoca) and from a collection trip in Tulcea county (Tulcea, Babadag), too. A monocanal energy spectrometer NK-350 (Gamma) has been used for measurements; impulses per minute have been registered and plant radioactivity expressed in Becquerel (Bq) units has been calculated. The highest values have been measured in the Agrobotanical Garden (alt. s.m. 475 m, incl. about 200 , exp. NE). Small-leaved low stature plants of Cyperaceae and Poaceae family have been much more radioactive than large-leaved Brassicaceae. In 28th May 1986 plants were generally more radioactive at basis as on top; older stems were 4-6 times more radioactive than top leaves or regrowth after harvest. Washing in running water (100 gr fresh weight in 50 l water for 5 minutes) reduced the radioactivity levels measured in different species with about 30%.