干旱区研究 ›› 2025, Vol. 42 ›› Issue (5): 840-851.doi: 10.13866/j.azr.2025.05.07 cstr: 32277.14.AZR.20250507

• 植物生态 • 上一篇    下一篇

基于探地雷达估算油松根系直径的方法

王勃1(), 张建军1,2(), 张海强3, 赖宗锐1, 赵炯昌1, 杨周1, 陆善洪1   

  1. 1.北京林业大学水土保持学院北京 100083
    2.山西吉县森林生态系统国家野外科学观测研究站山西 吉县 042200
    3.黄河水土保持天水治理监督局甘肃 天水 741000
  • 收稿日期:2025-01-01 修回日期:2025-03-17 出版日期:2025-05-15 发布日期:2025-10-22
  • 通讯作者: 张建军. E-mail: zhangjianjun@bjfu.edu.cn
  • 作者简介:王勃(1996-),男,硕士研究生,主要从事林业生态工程研究. E-mail: wangbo96824@163.com
  • 基金资助:
    国家重点研发计划(2024YFD2200500)

Method for estimating the diameter of Pinus tabulaeformis roots based on ground penetrating radar

WANG Bo1(), ZHANG Jianjun1,2(), ZHANG Haiqiang3, LAI Zongrui1, ZHAO Jiongchang1, YANG Zhou1, LU Shanhong1   

  1. 1. School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
    2. Jixian National Forest Ecosystem Observation and Research Station, Chinese National Ecosystem Research Network, Jixian 042200, Shanxi, China
    3. Tianshui Management and Supervision of Soil and Water Conservation of Yellow River, Tianshui 741000, Gansu, China
  • Received:2025-01-01 Revised:2025-03-17 Published:2025-05-15 Online:2025-10-22

摘要: 粗根对植株支撑与土壤固持意义重大,但在生态系统评价中仍无法做到精准快捷地确定粗根生物量。探地雷达(Ground Penetrating Radar,GPR)作为高效无损的地球物理学技术,能无损检测土壤根系信息。本研究在山西吉县蔡家川流域,利用探地雷达开展油松根系正演实验,借助EKKO-Project软件,提取探地雷达反射波参数、波速和时差值,建立根径拟合模型,综合分析反射波参数法、双层曲线法以及三维深度切片法3种根径估算方法在不同深度、不同根径大小和不同天线频率下的精准度与可靠性。结果表明:(1) 4种探地雷达反射波参数中,总时间间隔(ΣT)和根径的拟合效果最好,R2=0.7233,P<0.05。(2) 3种探地雷达根径估算方法中,天线频率为500 MHz时,双层曲线根径拟合效果最好(P<0.05)。(3) 三维深度切片根径拟合结果显示,1000 MHz频率天线探测识别效果优于500 MHz,其实际根径与估算根径平均相对误差分别为3.0 cm和8.7 cm,拟合可靠性差。综上,3种基于探地雷达技术的油松根系直径估算方法精度差异较大,双层曲线法对研究区的油松根系直径估算的精准度最好,在实际应用中可优先使用双层曲线法。

关键词: 探地雷达, 油松, 粗根, 根径估算, 晋西黄土区

Abstract:

The coarse roots play a significant role in supporting the plants and holding the soil firmly. However, in the evaluation of ecosystems, it is still impossible to determine the biomass of the coarse roots precisely and quickly. Ground Penetrating Radar (GPR), as an efficient and non-destructive geophysical technique, can non-destructively detect the information of soil roots. In this study, Pinus tabulaeformis root growth simulation experiment was conducted in the Caijiachuan River Basin of Jixian County, Shanxi Province, China using ground-penetrating radar. With the aid of the EKKO-Project software, the reflection wave parameters, wave velocity and time difference values of the ground-penetrating radar were extracted to establish a root diameter fitting model. The accuracy and reliability of three root diameter estimation methods, namely the reflection wave parameter method, the double-layer curve method and the three-dimensional depth slice method, under different depths, different root diameters and different antenna frequencies were comprehensively analyzed. The results showed that: (1) Among the four reflected wave parameters of GPR, total time interval (ΣT) and root diameter have the best fitting effect, R2=0.7233, P<0.05. (2) Among the three methods for estimating root diameters of ground-penetrating radar, when the antenna frequency is 500 MHz, the double-layer curve method has the best fitting effect (P<0.05). (3) The results of the three-dimensional depth slice root diameter fitting show that the detection and identification effect of the 1000 MHz frequency antenna is better than that of the 500 MHz antenna. The average relative errors between the actual root diameters and the estimated root diameters are 3.0 cm and 8.7 cm respectively, and the fitting reliability is poor. In conclusion, the accuracy of the three root diameter estimation methods based on ground-penetrating radar technology varies greatly. The double-layer curve method has the best accuracy for estimating the root diameters of Pinus tabulaeformis in the study area, and it can be used preferentially in practical applications.

Key words: ground penetrating radar, Pinus tabulaeformis, coarse root, root diameter estimation, loess area of Western Shanxi Province