Ahmed Mohammed Ahmed

 

 

Study of Heavy metal Accumulation in Soil and Some Plants in Erbil Governorate

 

 

SUMMERY

This study was conducted during dry season (October and September) 2015 to wet season (January and February) 2016, to study heavy metal accumulation in two plant species used for this purpose. Samples of topsoil and leaves of Nerium oleander and Phragmits australis inside and outside Erbil city have been collected in eight sites; 1 (City Centre), 2 (Turaq), 3 (Shawes), 4 (Hasarokan), 5 (New Zanko), 6 (Erbil-Koya road(Kani shawerdi village)), 7 (Hanara)  and 8 (control (Wsumallyan village)).

          In regard to plant studies, heavy metals (zinc (Zn), lead (Pb), nickel (Ni), manganese (Mn), arsenic (As), cupper (Cu), cobalt (Co), Iron (Fe), chromium (Cr), and cadmium (Cd)), total nitrogen were estimated in leaves in addition to determination of total chlorophyll content. Moreover, pH, EC, and particle size distribution for soil samples were determined.

          Mean values of hydrogen ion concentration (pH) in studied soil samples were ranged from 7.58 to 8.20. The highest pH value was recorded at site 8 (control) during dry season 2015, while the lowest value was measured at site 6 during wet season 2016. The collected soil samples were in alkaline side of neutrality. The results of electrical conductivity (EC) were fluctuated between 320µS/cm and 548µS/cm. The maximum value 548 µS/cm was recorded in site 2, whereas the minimum value 320 µS/cm was recorded in site 4 during dry season 2015. Results of Soil particle size indicated that the highest content of clay was 50% found in city centre, Turaq, Shawes, and Hasarokan during dry season, while the lowest percentage 30% was found in sites 1 and 2 during wet season 2016. The maximum value 45% of silt was recorded in site 4 during wet season, while the minimum value 12.5% was found in site 2 during dry season. In term of sand, the highest value 37.5% was observed in site 2 during dry season, but the lowest value 10% was found in site 4 during dry season. Accordingly, four types of soil texture have been detected clay, silty clay, silty clay loam and clay loam.

          The concentrations of heavy metals Zn, Pb, Ni, Mn, As, Cu, Co, Cr, and Cd in studied soil sample were;  40-109, 15-25, 66-131, 218-316, 3.38-8.43, 18-30, 11-14, 61-108, 0.10-0.30 mg.kg-1 respectively.

           The index of geo-accumulation (I geo) values revealed that Zn, Pb, Mn, As, Cu, Co, Cr, and Cd fell into class 1, while  Ni is greater than 1 (located within in class 2) during both seasons, due to anthropogenic activities in the studied area.

In term of plant accumulation view, total nitrogen percentage of all plant samples ranged from 0.50 to 1.50 %. In Nerium oleander L. plant, the maximum value 1.45 % was found at site 2 during dry season 2015, while the minimum value 0.50 % was recorded at site 7 during wet season 2016. Whereas, in Phragmites australis L. the maximum value 1.50 % was recorded at site 1 during dry season 2015, and the minimum value 0.64 %   was obtained at site 7 during wet season 2016. The total chlorophyll content of Nerium oleander was ranged from 0.33 to 1.41mg.g-1. Whereas, total chlorophyll content for Phragmites australis was ranged between 0.27 mg.g-1 at site 4 during wet season 2016, and 2.04 mg.g-1at site 1 during dry season 2015.

 Heavy metal contents (Zn, Pb, Ni, Mn, As, Cu, Co, Cr, and Cd) in both plants were determined. In Nerium oleander, the concentrations of Zn, Pb, Ni, Mn, As, Cu, Co, and Fe were ranging from; 26-41, 15-43, 0.60-22, 28-112, 1.70-3.10, 3.5-13, 1.70-2.40, and 35.87-59.94 mg.kg-1 respectively. In Phragmites australis the values of Zn, Pb, Ni, Mn, As, Cu, Co, and Fe were; 16.80-86, 18-80, 2.5-14.9, 55-121,1.7-4.4,3.5-12,1.5-1.9, and 31.75-48.72 mg.kg-1 respectively. In both plants, the level of Cr and Cd were undetectable in both plants at all studied sites.

The CF values of studied elements were less than one, that means both plant species (Nerium oleander L. and Phragmites australis L.) are excluder of Mn, Zn, Co, Cu, Fe, and Ni, while such plants were accumulators for Pb and As.

In this study, it was clear that there were statistical differences between levels of heavy metals accumulations as affected by studied sites and sampling periods. The highest values of studied elements were recorded during dry season in the sites in the city centre and near it.

 

posted : 20-6-2017

 

Leave a comment

rtp lakutoto prediksi lakutoto situs toto situs toto situs togel slot gacor toto togel 4d lakutoto laku toto laku toto laku toto laku toto slot gacor lakutoto lakutoto lakutoto lakutoto situs toto lakutoto agen togel terpercaya situs togel slot gacor toto macau toto togel situs toto situs toto lakutoto situs togel slot gacor bandar togel lakutoto lakutoto situs togel toto slot situs toto situs toto lakutoto lakutoto lakutoto situs toto togel 4d lakutoto situs toto laku toto lakutoto lakutoto toto slot lakutoto toto togel lakutoto situs toto agen togel lakutoto situs toto lakutoto slot gacor toto slot lakutoto bandar togel situs toto lakutoto lakutoto situs toto situs toto situs toto toto togel situs toto dapurtoto dapurtoto dapurtoto dapurtoto dapurtoto situs toto bandar togel situs toto situs toto toto macau toto togel situs toto situs toto situs toto situs toto situs toto situs toto dapurtoto toto togel toto slot toto slot bandar togel situs toto bo togel situs toto toto togel situs toto situs toto situs toto situs toto situs toto situs toto situs toto situs toto situs toto situs toto situs toto situs toto situs toto