基于探地雷达识别林地粗根和石砾  

Identification of coarse roots and rock fragments in woodland based on ground penetrating radar

作　　者：邱啟璜 牛健植[1] 王迪 吴昊阳 杨涛 杨书鉴 Qiu Qihuang;Niu Jianzhi;Wang Di;Wu Haoyang;Yang Tao;Yang Shujian(School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学水土保持学院,北京100083

出　　处：《北京林业大学学报》2023年第7期99-109,共11页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(41877154)。

摘　　要：【目的】通过1500 MHz探地雷达(GPR)对辽东老秃顶子国家自然保护区典型阔叶林蒙古栎地下粗根和石砾进行探测研究,对林木成林及其发挥水土保持功能提供理论参考。【方法】在试验样地内基于探地雷达探测技术,控制试验分析GPR反射波参数与根径和石砾直径的相关关系,建立有效的估算模型,识别林地粗根和石砾,确定其分布规律。【结果】(1)在控制试验条件下土壤粗根和石砾能有效识别,根径>1 cm的粗根在雷达剖面能形成明显的双曲线波形,石砾为“黑-白-黑”的波形。(2)GPR反射波参数中总时间间隔与根径相关性最显著(P<0.01),拟合得到y=0.2862x+1.18(R2=0.7098)的关系模型,石砾水平直径和垂直直径与各雷达反射波参数相关性都不显著。(3)剖面试验表明1500 MHz频率天线的GPR对粗根根系识别率为36.7%,对石砾识别率为17.9%。(4)剖面试验表明GPR对粗根识别及分布受根系的直径与埋深影响,而对石砾识别效果与它埋深相关性不显著。根径<3 cm的粗根主要分布在0~30 cm土层,>3 cm的粗根主要分布在20~40 cm土层。在有效识别的基础上,各根径根系在分布密度最大值的土层识别精度可达50%以上;GPR对石砾数量识别精度在20~30 cm土层达到最大值26.9%,在30~40 cm土层识别精度最小仅为8%。【结论】探地雷达在特定条件下能有效识别根系,且总时间间隔参数对粗根根径估计效果较好,对于石砾识别效果较根系差。[Objective]Ground-penetrating radar(GPR)of 1500 MHz was used to detect the underground coarse roots and rock fragments of the typical broadleaved forest of Laotudingzi National Nature Reserve in eastern Liaoning Province of northeastern China to provide theoretical reference for forest establishment and its function of soil and water conservation.[Method]Based on GPR detection technology in the test sample site,controlled experiments were conducted to analyze the correlations between GPR reflected wave parameters and root diameter and rock fragment diameter,and an effective estimation model was established.The coarse roots and rock fragments in the study stand were identified and their distribution patterns were determined.[Result](1)In the controlled experimental condition,the coarse roots and rock fragments can be effectively identified.The coarse roots with root diameter>1 cm can form obvious hyperbolic waveform in the radar profile,while the rock fragments were the“black-white-black”waveform.(2)The correlation between total time interval and root diameter was the most significant(P<0.01),and the fitting model Y=0.2862x+1.18(R2=0.7098)was obtained.The horizontal and vertical diameters of rock fragments had no significant correlation with the parameters of each radar reflection wave.(3)The profile test showed that the GPR with 1500 MHz frequency antenna had a recognition rate of 36.7% for coarse roots and 17.9% for rock fragments.(4)The results of profile test showed that the GPR effect on the identification and distribution of coarse roots was affected by the diameter and buried depth of roots,but the effect of GPR on the identification of rock fragments was not significantly correlated with its buried depth.The coarse roots with root diameter<3 cm were mainly distributed in the 0-30 cm soil layer,and the coarse roots with root diameter>3 cm were mainly distributed in the 20-40 cm soil layer.On the basis of effective recognition,the recognition accuracy of each root diameter in the soil layer with the maxi

关 键 词：探地雷达 目标识别 林地粗根 土壤石砾 分布估计 

分 类 号：S714[农业科学—林学]