摘要
高精度快速探测土壤表层水分状况,对于精准农业生产、水资源精确管理及防治坡耕地水土流失具有重要意义。现有探地雷达（ground penetrating radar,GPR）低频探测技术不能满足表层土壤含水量高精度要求,需要发展和应用高精度探测技术。本研究采集江宁某蔬菜地水稻土表层（0～20cm）土壤（粉砂质黏壤土）,通过室内模拟试验,利用高频（1 GHz和2 GHz）探地雷达在不同土壤含水量状况下进行探测,获取GPR数据图像信息,提取电磁波谱特征参数,分析其与土壤含水量之间的定量关系。结果表明：1 GHz和2 GHz频率GPR探测的土壤介电常数ε与实测土壤含水量θ拟合的ε～θ模型决定系数R^2分别为0.94与0.97,高频探地雷达技术预测粉砂质黏壤土表层土壤含水量是可行的;与低频探地雷达技术相比,高频探地雷达技术能够高精度探测表层土壤含水量。
Rapid high-precision determination topsoil water content is of vital importance toprecision agriculture,precise water resource management and the control of slope land erosion. The technology of low-frequency ground penetrating radar（GPR）currently in use is far from the requirement in precision for determination of topsoil water content. It is,therefore,essential to develop and adopt a high-precision detection technology. In this paper,the technology of high frequency（1 GHz and 2 GHz）Ground Penetrating Radar（HFGPR）was tested to determine topsoil water content in a vegetable field of silty clay loam in soil texture in Jiangning of Nanjing,China. HFGPR was used to determine topsoil water content of farmlands under different soil water content,GPR data and images were obtained and electromagnetic spectrum characteristic parameters extracted for analysis of their quantitative relationships with soil water content. Results showed that：The coefficient R^2 of ε-θ model decision in fitting the soil dielectric constant（ε）obtained by the 1 GHz and 2 GHz frequency GPR with the soil moisture（θ）measured in the field was 0.94 and 0.97,respectively,which demonstrates that the technology of high frequency GPR is feasible be applied to determine the soil water content in the topsoil of vegetable fields of silty clay loam soil. The new technology is much higher than the old one in precision in determining soil water content in topsoil layers.
出处
《土壤学报》
CAS
CSCD
北大核心
2016年第3期621-626,共6页
Acta Pedologica Sinica
基金
国家自然科学基金项目(41571206
41501296)资助~~
关键词
探地雷达
土壤含水量
介电常数
电磁波波速
土壤质地
GPR
Soil water content
Soil dielectric constant
Velocity of the electromag netic wave
Soil texture
