土壤中植物根系的层析成像检测试验

A Test of Root Imaging in Soil Based on CBCT

针对植物根系难以在大尺寸土壤介质中实现有效成像的技术难题，本文采用基于平板探测器的160kV小焦点锥柬CT设备，选用直径分别为210mm和120mm两种尺寸不同的6个土壤样品进行植物根系的原位成像检测试验，以期找出影响其原位根系成像的主要因素和影响规律，进而实现较大尺寸土壤样品中植物根系的层析成像。结果表明，通过增加管电压、管电流水平，采取适当滤波、几何校准、伪影校正和优化重建等改进措施，采用现有CBCT成像检测系统能够实现在200mm以上的大尺寸土壤介质中获取根系的原位断层图像；且土壤颗粒越均匀、尺寸越小，获得的原位根系层析成像质量越好。

In order to solve the technical problem of root imaging in larger-scale soil sample, a 160kV minifocus X-ray Cone-beam Computed Tomography （CBCT） was used in this paper to do a test for root imaging in six soil samples with the diameters of 210 mm and 120 mm. It is shown in the result that Using the CBCT system available is possible to implement plant root imaging in larger soil samples with over 200 mm diameter by the means of increasing tube voltage and current, effective filtering, system correction, artifact correction, corresponding parameter setting and improving reconstruction, and then the imaging quality of samples＇ slices is better while soil particle is smaller.