A study of nutrient recycling in a plant-soil system using NAA

To understand how nutrients are recycled in a particular soil - plant system, we have analyzed the kinetics of the elements Na, Mg, K, Ca, Mn, and Br throughout the life cycle of the plant. The plant sample was collected at 6 different stages of its growth. The effect of V (100 μM) on the element recycling system was also analyzed. The amount of the elements in each tissue of the plant, root, stem, petiole, leaf, and seed, were then determined by neutron activation analysis. The total elemental uptake rapidly increased when the plant developed from the juvenile to the adult phase. More than half of the Mg and Mn in cotyledon was transported to the younger leaves before the cotyledon was shed. From the pattern of movement of each element in plant tissue we have constructed an element recycling model in the soil-plant system. Based on the model, it was found that the amount of K to be a limiting factor for the recycling activity in the system. (author)