Effect of direction and distance from the Parham-Zinc factory of Zanjan on zinc concentration and translocation factor in Hulthemia persica and Chenopodium album

Contamination of soil and plants with heavy elements including zinc, due to industrial activities, might have significant adverse effects on human health. Industrial factories and mines, fertilizers, pesticides and waste water are the most important sources of water, soil and plants contaminations. In Zanjan province, there is a wide range of zinc processing and production factories and mining activities that can contaminate soil, water and plants. The aim of this study was to investigate the zinc concentration of the soil, shoot and root and zinc translocation factor (TF) in dominant rangeland plants (Hulthemia persica and Chenopodium album) in different distances and directions from factory.
This study was conducted as factorial in a completely randomized design with three replication. The experimental treatments included three directions (northeast, east and west of the factory), six different distances from the factory (0-250, 250-500, 500-7500, 750-1000, 1000-1250, 12500-1500 meters) and two plants (Hulthemia persica and Chenopodium album). The soil and plant samples were collected from the selected sites. Shoot and root samples were digested by concentrated nitric acid and available zinc in soil was extracted by DTPA. The zinc concentrations were measured by atomic absorption spectroscopy.
The results showed that the effect of direction and distance from the factory was significant on zinc concentration of shoot and root and also translocation factor, (P In the northeast direction (dominant wind), plant and soil pollution was mostly influenced by wind. The main contamination factors of the soil and plant at distances close to the factory were waste water and waste in the east and west direct, respectively. Hulthemia persica, with a broad and thick root system, was able to absorb more zinc and transfer it to the shoot part. But in the northeast direction, the atmospheric deposition of the factory played an important role in soil and plant contamination. Chenopodium album with high vegetation biomass absorbed more zinc from the air in its shoot than Hulthemia persica with rough and blubber stems. For this reason, in the dominant wind direction, the TF was also found in the Chenopodium album at as far from distances higher than Hulthemia persica. Therefore, the absorption of atmospheric zinc was higher in Chenopodium album. In waste disposal areas, Hulthemia Persica had a more translocation factor.