TOTAL HEAVY METAL CONTENTS IN SERPENTINITE SOILS FROM TÜRKOĞLU-KAHRAMANMARAŞ/TURKEY

ABSTRACT

In this study, total heavy metal distributions in serpentinite soils from Türkoğlu-Kahramanmaraş region SE Turkey were investigated. Common ultramafic rock types (dunite, harzburgite, lherzolite, wehrlite) and the secondary alteration products formed by their hydration within the Earth’s crust (serpentinite) are the primary source of serpentinite soils. The characteristics of soils developed on serpentinite and peridotite differ from other soils. Numerous studies have reported that typical heavy metal enrichment in ultramafic soils. Serpentinite-derived soils have high concentrations of Cr and Ni from the parent materials and carry a risk to human health and environmental quality. Soils contaminated with heavy metals represent an escalating problem for all living organisms, such as plants, animals and humans. A total of 15 soil samples were taken from 0-30 cm depth which developed on serpentinite and peridotite parent materials in Türkoğlu district in the South of Kahramanmaraş city. Collected soil samples were air-dried, thereafter breaking the agglomerates by using a wood hammer, then sieved through a 100 μ sieve and stored in plastic bags. Later, the concentration of heavy metals including Ni, Cr, Co, Fe and Mn were measured using an X-ray fluorescence. According to the obtained datas, the total Cr, Ni, Co, Mn and Fe contents of the soils varied from 2085 to 5644 mgkg-1, 1595 to 2833 mgkg-1,103 to 187 mgkg-1, 922 to 1680 mgkg-1, 9.49 to 15.83 %, respectively. This study revealed that serpentinite soils are characterized by high concentrations of heavy metals such as Ni, Cr, Co, Mn and Fe. This high level of Ni, Cr, Fe, Mn and Co is obviously toxic and can adversely affect plant growth. Concentrations of Fe, Ni, Cr, Mn and Co were very high and present in the order of Fe>Cr>Ni>Mn>Co. Heavy metals which accumulate in the different plant parts results in the toxicity of plants. Chromium at higher concentrations becomes toxic for the plants and results in the detrimental effect. High concentrations of Ni in plants are toxic and causes severe chlorosis and necrosis and host of other growth abnormalities and anatomical changes. In areas where such heavy metal concentrations are above the limit values, the cultivation of plant species accumulating heavy metals in the root zone is important for environment, human and plant health.

Keywords: Heavy metal, Ophiolite, Peridotite, Serpentinite, Soil