METHOD FOR DETERMINATION OF DURATION OF RESIDUAL EFFECT OF PHOSPHORIC FERTILIZERS

摘要

A method for the determination of duration of residual effect of phosphoric fertilizers includes sampling the topsoil layer, carrying out chemical analysis with determination of movable forms of phosphor, statistical-mathematical processing of the data obtained, getting characteristics of the level of soil provision with phosphor. Statistical-mathematical processing is carried out on the basis of the base of long-term investigations completed with data obtained above, with determination of the law of change of phosphate state of soil after the last introduction of phosphoric fertilizers and on the basis of the data obtained a mathematical model is constructed with obtaining regression equation, by means of that one duration of residual effect of phosphoric acids is predicted:PO=17.5896-0.2975X+0.0011X,wherein PO calculated content of movable forms of phosphor, mg PO/100g of soil;X number of years of residual effect of phosphoric fertilizers;17,5896 equation constant.