In order to investigate the root uptake and migrational behavior of radionuclides deposited into the farm-land during crop cultures, rice and soybean were cultures on lysimeters installed in a greenhouse and the solution of mixed radionuclides such as Mn-54, Co-60, Sr-85 and Cs-137 was distributed over the land surface on different growth stages of the crops. For Chinese cabbage and radish, the second year`s radio-tracer experiments were carried out. Several procedures for the chemical analysis of plutonium in environmental samples were tested and alpha-spectrometry system for the isotope analysis was established. The usefulness of the analysis technique in the environmental monitoring program was examined by practising the technique with soil samples. (Author).