Some kinetic properties of Urease and phosphatase (alkaline and acid)and enfluence of temperature and salinity

Abstract

Two soils were choosen the first was silty clay loam (SiCL) and the second was loamy sand (LS) from Diwaniyah city. Two enzymes were choosen They were urease and phosphatase ( a lkaline and acid ) to study some kinetic properties for enzymes in soil and to study some factors effected on enzymes activity in soil (temperature degrees and salinity). The results showed that (Vmax) and (Km) in (SiCL) soil was higher than (LS) soil for both enzymes Urease and phosphatase (alkaline and acid). (Km) values were very lowest when the (Vmax) values were very highest in both soils and both enzymes.The results showed that the Urease and phoslphatase (alkaline and acid) activity were increased with increasing of temperature degrees in both soils.The highest values of activity were in the (SiCL) soil for both enzymes. The increasing of soil salinity decreased enzymes activity in both soils, and highest inhibitor percent was in the (SiCL) soil for urease and alkaline phosphatase but acid phosphatase, has a highest inhibitor percent in (LS) soil.