ALKALINE AND ACID PHOSPHATASE ACTIVITY IN SOIL TREATED WITH MINING LEACHING SOLUTIONS

CARRERA, S. E.; MESSINA, G. A.; MARCHEVSKY, E; STEGE, P. W.

Potrero de los Funes

Congreso; XXX Reunión Anual de la Sociedad de Biología de Cuyo; 2012

Mine leaching involves the use of cyanide usually in gold, silver, and copper ores, which merits great attention because of the serious environmental and public safety impact. Nowadays, two compounds capable of complex gold have been proposed to be used in the leaching process. Those compounds are thiourea and thiocyanate, which are used mostly as moisture. Phosphatases (phosphoric monoester hydrolases) are required to mineralize organic P to release it as specie available for the plants. Microbial phosphatases are found to be more efficient in hydrolysis of organic P compounds than the phosphatases of plants. Among the hydrolases, acid phosphomonoesterase activity is the most frequently used enzyme for estimating changes in soil quality. These enzymes are classified as acid phosphatase (AcP) and alkaline phosphatase (AlP) according to their optimum pH. This enzyme is an important index of the quality and quantity of organic matter in the soil. The aim was to measure the changes in the activity of phosphatases exposed to different concentration of the cyanide, thiourea and tiocianate compounds at concentration using in a real mining process. Results were evaluated using c2 test. The AcP and AlP activities were higher in soils affected by tiourea compared with tiocianate. In soils treated with cyanide both enzyme activities suffer a significantly decrease. In all the studies a positive control were represented by a soil with any disturbance.