Using Cedrus atlantica's annual rings as a biomonitor in observing the changes of Ni and Co concentrations in the atmosphere

Among the environmental pollution elements, one of the most important problems of the world today, air pollution and heavy metal pollution that have gradually increased after the industrial activities, are of significant importance. Heavy metals are not easily dissolved in nature. Moreover, they tend to bioaccumulate in living organisms, and some of them have a toxic or carcinogenic effect even at low concentrations. For this reason, it is crucial to monitor the heavy metal concentration in the air and monitor the changes. One of the efficient methods in observing the change of heavy metal concentrations in the air is the use of annual rings of trees as a biomonitor. The present study aimed to determine the annual change of Ni and Co concentrations, which are among the heavy metals related to traffic volume at most, in annual rings of Cedrus atlantica harvested in Kastamonu in late 2019. Within the scope of this study, the heavy metal concentrations in the inner and outer bark were compared to the heavy metal concentration in wood and the change of concentration in terms of direction was also analyzed. As a result of the present study, the highest concentrations in both heavy metals were found in the outer bark, whereas the transmission of metals within the wood was limited. It was found that Ni concentration significantly changed directionally in woods, and this change was related to the traffic volume. Thus, it was concluded that the annual rings of Cedrus atlantica were very suitable biomonitors to monitor Ni concentration change.