CHANGE PRODUCED IN THE POTASSIUM QUANTITY -INTENSITY RELATIONSHIP OF SOME ARGENTINE SOILS AFFECTED BY CONTINUOUS TILLING

The parameters obtained from the Q/1 isothermes have been used by seve ral authors as criteria to estimate the immediate availability of labi le K in a soil. The aim of this work is to study how these parameters have been modified in different agricultural soils of the country whic h have been cropped for more than 10 years. It was observed that DELTA K(L), DELTA Ko and ARe have decreased while the PBC has remained cons tant in some soils and it has decreased in anothers. In all the soils the low PBC values indicate that these soils would present potassium d eficiency under intensive cropping.