Оценка предельно допустимых концентраций тяжелых металлов в почвах с учетом взаимосвязей свойств почв

Abstract

It has been proved in the work that admissible concentration limits of mobile fraction of heavy metals in the soils have to be additionally rated for the water- soluble fractions taking into consideration the rate of the ion transition into solution and soil deposit capacity, with respect to environment pH, as pH = 4,8 in the CH3COONH4 exudate basically does not appear in the soils. The admissible concentration limits have to be assessed due to the soil characteristics combination which determines heavily the concentration of heavy metal water-soluble fractions (efficient solubility of their deposits, effective constants of the ion exchange and effective constants of the complex instability). The correlation of water-soluble fractions of heavy metals depending on pH in the common black soils was: for Pb = -0,40; for Cd = -0,32; for Co = -0,39; for Ni = -0,47. The proportion of positively charged species not linked into complexes increases under the pollution augment in the soil. This way, PbL7PbL+ ratio was 0,33±0,01 in the check, under the pollution it was Pb - 0,08±0,01. The feedback systems on photosynthesis activity, sprout development, microbial flora change, genetic tests on drosophila are offered for the assessment of the heavy metal influence over the biotests. Keywords: HEAVY METALS, ADMISSIBLE CONCENTRATION LIMITS, BIOTESTS