项目名称: 基于探地雷达技术的盐碱地地下分层导电特性无损探测方法研究
项目编号: No.41301368
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 天文学、地球科学
项目作者: 吴斌
作者单位: 中国科学院东北地理与农业生态研究所
项目金额: 25万元
中文摘要: 盐碱地的改良对粮食增产具有十分重要的意义。空间光学和微波遥感方式能够对盐碱土表层介电特性等参数进行有效探测。探地雷达具有一定的穿透能力和较高的垂直分辨率,可以探测盐碱地浅层地下的导电特性分布情况,进而为盐碱地地下水盐分布特征的探测提供了可能。 本课题针对盐碱地地下分层导电特性的探地雷达无损探测方法开展研究,采用波动方程法对不同地下介质结构参数的盐碱地进行频域内正演分析,根据合成后的频域响应经傅氏反变换获得探地雷达时域回波,以此建立回波波形先验知识库;采用时域回波波形知识库查找表法和频域波动方程求解法对盐碱地地层结构的厚度和介电特性等参数进行反演,从而实现盐碱地地下分层导电特性的无损探测,其探测深度0~5m,垂直分辨率≤20cm,该技术将与空间遥感技术组成盐碱地完备的探测体系,为盐碱地改良和促进农业增产提供有效的信息技术支持。
中文关键词: 探地雷达;盐碱地;波动方程;电导率反演;
英文摘要: Remote Sensing Method can achieve monitoring wide spread saline-alkali soil area rapidly, and it play very important role in saline-alkali management and improvement. Under the limitation of electromagnetic wave frequency, the spectrum, active and passive microwave remote sensing method can't penetrate soil effectively, on the contrary, the low frequency electromagnetic induction method can penetrate the soil, but has low vertical resolution. Metric waves ground penetrating radar(GPR) can emit and receive the electromagnetic echo from a few meter depth under ground, this advantage give GPR the ability to achieve nondestructive survey on underground structure parameter of saline-alkali soil. This subject is aimed at the nondestructive survey on underground structure parameter of saline-alkali soil problem. We propose the forward and frequency domain analysis method on the underground structure parameter of saline-alkali soil based on wave equation, then we can synthesize the time domain echo according to the frequency domain respond, and establish the wave form library. At last, we perform the inversion progress on underground structure parameter, dielectric constant and medium layer thickness, of saline-alkali soil. Our research can provide theory and practice basis to achieving nondestructive survey on undergro
英文关键词: ground penetrating radar;saline-alkali soil;wave equation;conductivity inversion;