357 Journal of Forest Science, 67, 2021 (7): 357–366 Original Paper https://doi.org/10.17221/37/2021-JFS Accumulation of heavy metal pollution caused by trafc in forest trees in the park of Kerey and Janibek Khans of the city of Nur-Sultan, Kazakhstan Sezgin Ayan 1 *, Dani Sarsekova 2 , Gani Kenesaryuly 2 , Ergin Yilmaz 3 , Orhan Gülseven 3 , İlknur Şahin 4 1 Silviculture Department, Faculty of Forestry, Kastamonu University, Kastamonu, Turkey 2 S. Seifullin Kazakh Agro Technical University, Faculty of Agronomy, Forest Resources and Forestry, Nur-Sultan, Kazakhstan 3 Sustainable Forestry Doctoral Programme, Institute of Science, Kastamonu University, Kastamonu, Turkey 4 Forestry and Natural Turism Specialization Coordinatorship, Kastamonu University, Kastamonu, Turkey *Corresponding author: sezginayan@gmail.com Citation: Ayan S., Sarsekova D., Kenesaryuly G., Yilmaz E., Gülseven O., Şahin İ. (2021): Accumulation of heavy metal pollution caused by trafc in forest trees in the park of Kerey and Janibek Khans of the city of Nur-Sultan, Kazakhstan. J. For. Sci., 67: 357–366. Abstract: Air quality in Nur-Sultan, the fast-growing new capital city of Kazakhstan, has been poorly investigated. Tis research was carried in Kerey and Janibek Khans Park in Nur-Sultan, the capital city of Kazakhstan, which is afected by “diferent trafc density” on the roads. Tree diferent categories of contamination (i) high pollution (distance from the main road 10–15 m), (ii) moderate pollution (distance from the side road 15–30 m), and (iii) low pollution (distan- ce from the source of contamination 30–80 m) at diferent levels resulting from urban transportation were examined. Te aim of the study is to determine the pollution accumulation amounts of Ni, Cd, Pb, Cr, Li, Co, Fe, and Zn in fve diferent tree species: Norway spruce (Picea abies /L./ H. Karst.), blue spruce (Picea pungens Engelm.), Scots pine (Pi- nus sylvestris L.,), Siberian larch (Larix sibirica Ledeb.), and silver birch (Betula pendula Roth). Signifcant diferences in Ni, Cd, Pb, Cr, Li, Co, Fe, and Zn accumulation amounts were determined between three diferent parts of the park exposed to diferent levels of contamination. Approximately twice higher Ni, 2.3 times Cd, 3.3 times Pb, 2.7 times Co, 1.6 times Zn accumulation were determined in the area exposed to high pollution than in the parts of the park exposed to low pollution. Cd deposition in the area exposed to high contamination was higher in silver birch than in Scots pine and Norway spruce, while Cr and Co deposition values were higher in Norway spruce than in birch and Scots pine. Keywords: anthropogenic emission; contamination; heavy metals; Norway spruce; Scots pine It is known that the anthropogenic emissions of air pollutants and then precipitation with heavy metals lead to side efects on both chemical and biological processes in soils and on plants. Espe- cially, larger areas in the northern hemisphere are contaminated by several heavy metals through in- dustrial and trafc-induced atmospheric deposi- tion (Steinnes, Friedland 2006). Vehicles are one of the primary sources of air pollution in cities. Many pollutants emerge due to vehicles (e.g. ex- haust gases, car wheels) (Ugolini et al. 2013). Pol- lutants lead to the visual pollution on plants, they also cause a change and delay in physiological and metabolic events with their accumulation on dif- ferent parts of plant. Sarkar et al. (1986) stated that exhaust gas pollution accelerates peroxidase and catalytic activities in large leaves of natural plants, and the distance from the road is closely related with the catalytic activities of plants. Amit et al. (2000) specifed that the cuticle and epidermal