基于Pro/E的土壤结构与小麦幼苗期根系关系模拟与分析

【目的】探讨一种不仅可以对作物根系进行3D重构的技术手段,而且实现对根系及土壤结构各指标以及二者相互关系的计算方法,从而为根土系统的研究提供一种通用且兼备造型和计算分析功能的技术路径。【方法】运用Pro/E软件的造型功能对实测小麦根系的空间坐标数据进行3D重构,计算表征小麦根系与土壤结构关系的指标,进而使用这些指标分析比较旋耕和免耕两种耕作处理下的根土关系动态变化。【结果】在各监测期内免耕处理的小麦根系总长大于旋耕处理,不过在播后的28d之内免耕处理的根系水平夹角显著高于旋耕处理,这一关系又在播后42—70d消失。免耕的根系主轴扩展土体体积总大于旋耕,而且二者的包络土体体积和单位根系长度有效土体体积也具有同样的特征。在小麦生长的前56d内包络土体体积和单位根系长度的有效土体体积呈现增长的趋势,而在56—70d这两个参数值急剧下降。【结论】Pro/E开发平台能够提供丰富的3D根土系统造型及计算分析功能。根系水平夹角、根系主轴扩展土体体积、根系包络土体体积、单位根系长度有效土体体积是表征根土关系的描述指标。运用这些指标可以对耕作引起的土壤结构状态,以及耕后土壤结构与小麦根系关系的动力学演变过程进行跟踪和定量。

Modeling and Analyzing the Relationship Between Soil Structure and Wheat Seedling Root with Pro/E

【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.