Alkaline and acid phosphatase activity in soil treated with mining leaching solutions.

SEBASTIAN CARRERA; GERMÁN A. MESSINA; EDUARDO MARCHEVSKY; PATRICIA W. STEGE

San Luis

Congreso; Sociedad de biología de cuyo; 2012

Sociedad de biología de cuyo

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. These compounds are used mostly as moisture. The 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. Thus, the aim of this work was measure the changes in the activity of phosphatases enzyme exposed to different concentration of the cyanide, thiourea and tiocianate compounds at concentration using in a real mining process. The results obtained in the present work were evaluated using χ2 test. Significance was set at a P value of ˂0.05. The activity of the acid phosphatase (AcP) and alkaline phosphatase (AlP) were higher in soils affected by tiourea compared with tiocianate. In soils treated with cyanide both enzyme activities suffer a significantly decreased. In all the studies a positive control were represented by a soil with any disturbance.