中文摘要：

应用探地雷达对植物根系进行探测的有效性已得到证实.但由于根系结构复杂,根围环境异质性强,针对基于探地雷达得到的根系探测数据的解读尚处于经验积累阶段.本研究首先通过对比根系探地雷达实测信号图像和模拟信号图像,证实了利用GprMax模拟探地雷达探测植物根系的有效性.其次通过定义不同根系空间结构和电性参数场景,模拟了不同条件下根目标反射信号的差异,并对影响探地雷达探测植物根系有效性的敏感因素进行了初步分析.模拟结果有助于探地雷达野外根系探测图谱的解译,为探地雷达在植物根系探测中的应用积累经验.

英文摘要：

Roots play a crucial role in plant ecosystem. Traditional methods for roots measurements are destructive and labor intensive, limiting the manageability of the size and number of sampling. Ground-penetrating radar （GPR）, a nondestructive root analysis method, has already been testified as a feasible and efficient root detection method. However, it is difficult to idetify roots from GPR radargrams. The complexity of root systems and heterogeneity of rhizosphere make the application of GPR to root detection arduous. The feasibility of using GprMax, a GPR profile forward simulation software based on Finite Difference Time Domain （FDTD）theory, for root GPR reflection profiles modeling was validated by comparing simulation results and field experiment results. Furthermore, through developing various forward simulation models, the effect of sensitive factors in using GPR for detecting plant roots was analyzed. Simulation results show that antenna frequency, root system configuration, root water content, root size and depth have obvious impact on root GPR profiles. Conclusions from this paper will help the interpreting of roots GPR reflection profiles and the application of GPR to root detection.