Modeling Root Depth Development with time under some Crop and Tillage Management System

Abstract

Five empirical models for the prediction of root depth developed with time under four combinations of crop and tillage management systems have been developed by the method of polynomial regression. Root depth predictions by a general model were severally correlated with root depth predictions by the combination-specific models and measured root depth data from five grown under four combinations of crop and tillage management. Root depth development with time assumed a curvilinear trend and was best described by polynomial equations, of order four, with correlation coefficient(r) between 0.961 and 0.974. Root depth predictions by the general model correlated well with both the root depth predicted by the combination-specific models (0.996≤ r ≤1.00) and the measured root depth data (0.849≤ r ≤0.996), thus indicating that the general and combination-specific models can be used interchangeably in predicting root depths under any of the four crop and tillage management combination studied.

JARD Vol. 1 2001: pp. 51-66