Investigation on Heavy Metal Pollution in Uludag Fir Forests (Abies nordmanniana subsp. bornmulleriana MATTF) in the Bartin Region

Abstract

In this study carried out in pure Uludag fir forests of Bartin-Ardic district the change of amount of heavy metals in both soil and needles of Uludag fir depending on altitude was investigated. For this reason, experimental areas were established in three different altitude levels (1,000 m, 1,100 m and 1,200 m) and changes of heavy metals were determined in the soil and Uludag fir needles. According to the results obtained from this research, soil and plant contamination by heavy metals is increasing nowadays while the heavy metal (Pb, Zn, Ni, Cu, Cd, Mn, Cr and Fe) concentrations decreased with the increase in altitude. The highest levels of Cd, Cr and Fe were found in the composite soil and needle of Uludag fir adjacent to 1,000 m and other altitude levels. However, there are significant differences at the P<0.01 level according to the results of ANOVA in the amount of heavy metals in both soil and needle of Uludag fir depending on the altitude levels. The Duncan test was also applied and three different groups were found (exception of Cd); the changes of the amount of heavy metals in soil and needle of Uludag fir depends on the altitude level at the P<0.01 significance level. In this context, the area should be carefully monitored in order to detect changes in the long-term risk due to the presence of high concentrations of trace elements in soils. Toxicological tests and risk assessment will also be carried out with newly polluted soils and trees (Uludag fir) from this site to evaluate the actual environmental risk of trace elements and their transfer to the food chain. The grape plant had behaved as a metal indicator for Pb, Mn, Zn, Fe, Cu, Cr and Cd, indicating that it can be used for testing changes in metal availability in soils. The concentrations of metals in both plant species exceeded the limits established for humans and grazing animals impling a health risk linked with the spread of pollution from mining sites to Uludag fir forests in the Ardic district.