Abstract:

【Objective】 A 3D modeling technique was investigated for both topological reconstruction of crop root and the computation of relative criteria of the crop root and soil structures and their correlations. So that a general-purpose technical approach was provided for the modeling and analyzing the demand in the soil-root system studies. 【Method】 The measured wheat root data was reconstructed into 3D models in Pro/E platform, then the calculation of related criteria to quantify wheat root and soil structure was performed. The result was then used to quantify the dynamical change of the root-soil system for different tillage treatments including no-tillage and rotary-tillage. 【Result】 In each monitoring period total wheat root length in no-tillage was longer than that in rotary-tillage. Whereas the horizontal angle of the no-tillage treated wheat root was higher than that of the rotary-tillage in the first 28 days after sowing. During the following 42-70 days the two angles turned into the same level. Root-axis-expanded soil volume from no-tillage was always larger than that in rotary-tillage. This trend was also true for enveloping soil volumes and effective soil volumes for unit root lengths. In the first 56 d period the enveloping soil volumes and the effective soil volumes for unit root lengths exhibited a positive increasing trend, but then were drastically decreased in 56-70 days. 【Conclusion】 Pro/E platform provides powerful functions for 3-D root-soil system modeling and calculating and analyzing. Root length, root-axis-expanded soil volume, enveloping soil volumes and effective soil volumes for unit root lengths are suitable indices for root-soil system quantification. They can be used for monitoring and evaluating tillage-induced soil structure and the dynamics of the soil structure and root interrelationship, which is beneficial to mechanism interpretation of soil tillage and crop establishment.

Key words: Pro/E modeling, wheat root system, soil structure, dynamic process