ASSESSING THE HEAVY METALS BIOACCUMULATION OF Pinus brutia TEN. URBAN TREE IN DUHOK, KURDISTAN REGION OF IRAQ

Abstract

Worldwide modern urbanization generates with a wide range of environmental challenges affecting adversely on human health and well-being such as emission of air pollutant particles. Nowadays in Kurdistan Region context, most cities are in a rapid urban development, thus they eventually effect on the urban environment quality through raising the level of air pollution. Furthermore, both scientific communities and political decision-makers have taken a little attention to the role of trees as heavy metal bioindicators of air pollution. Therefore, the main goal of the present study is to assess both how the heavy metals are spatially distributed within different urban areas and emphasize on the important role of the urban forest in improving human health in Duhok province. The current study evaluates the bioaccumulation of some heavy metals (lead, cadmium and copper) by urban tree leaves (Pinus brutia) that are randomly distributed. Localities have been selected according to the following categories: city Centre, highways, peri-urban areas, and natural areas. For the determination of heavy metals bioaccumulation in both soil and leaves the protocol of (Martens & Lindsay, 1990) were followed. The results highlighted that the Pine tree is a successful bioaccumulator for heavy metals in Duhok urban areas. Moreover, the tree leaves take up and accumulate more heavy metals than soil. It was also shown an elevated levels of heavy metals in both soil and plant leaves with the increase in urbanization and crowdedness. Interestingly, the heavy metals investigated in tree species and soil were above the safe ranges in most urbanized locations, particularly in highway and city center. In this regard, the green spaces in general and safety greenbelt in particular should become an essential part in any urban design. However, more studies and investigations are required to show the effectiveness of other tree species as bioaccumulators in order to provide them in our urban areas to accumulate heavy metals and minimize the level of air pollution in Duhok city