Evaluation of cement dust effects on soil microbial biomass and chlorophyll content of Triticum aestivum L. and Hordeum vulgare L.

Abstract

<strong>ABSTRACT: </strong>Overall plant growth and microbial biomass can be effected by dust accumulation. The chloroform fumigation-extraction method was used to evaluating the effect of cement dust pollution emitted from Kurdistan cement factory on soil microbial biomass carbon. Chlorophyll content (a, b and total) of plants species was measured in different distance from cement factory. Microbial biomass C (C_mic) amounts ranged from 0.138 to 1.102 mg/g soils in the polluted sites and from 0.104 to 1.283 mg/g soils in the control area. Soils polluted with alkaline cement dust resulted in meaningful reduction in C_mic levels compared to control soils. Pearson correlation coefficients (r) show C_mic was positively correlated to soil CaCO₃ content (r = 0.09). C_mic/C_org ratio was 2.54 and 1.92 in the control and cement polluted sites, respectively. Reduction in this ratio can be resulted from soil degradation in cement polluted soils. A significant decrease in the C_mic/C_org ratio in cement dust-polluted soils illustrated that this factor can be applied as a good indicator of soil quality. In the case of chlorophyll content of plant species, maximum reduction of total chlorophyll for Triticum aestivum L. was 45% compared to Hordeum vulgare L. with 60%. Therefore, results show higher sensitivity of H.vulgare than to T. aestivum.