干旱地区农业研究2024，Vol.42Issue(1)：261-269,9.DOI:10.7606/j.issn.1000-7601.2024.01.27
基于介电频谱特征参数的红壤干旱指标评价研究
Evaluation of red soil drought index based on dielectric spectrum characteristic parameters
摘要
Abstract
The purpose of this study was to obtain the response characteristics of red soil moisture content to the dielectric spectrum of electromagnetic wave and discuss the feasibility of dielectric spectrum characteristic pa-rameters as the evaluation red soil drought index.The frequency domain dielectric spectroscopy(FDS)test of red soil with different volume water content was finished,and the integral value of the dielectric spectrum characteristic curves was extracted to analyze the correlation between the dielectric spectrum characteristic parameters and the vol-ume water content.Combined with the national agricultural drought grade standard,the red soil drought evaluation indexes based on dielectric spectrum characteristic parameters were proposed.The results showed that the real and imaginary parts of the dielectric constant of red soil gradually decrease with the increase of the frequency of the die-lectric spectrum,and both were positively correlated with the volumetric water content.The dielectric loss factor fluctuates with the increasing frequencies,the smaller the volumetric water content,the stronger the fluctuation,and a trend of decreasing first and then increasing was showed.The quantitative relationship between the character-istic parameters of the dielectric spectrum and the volumetric water content was given by the least square method.The bacterial foraging algorithm was used to determine the optimal model coefficients,and the fitting accuracy was greater than 0.95.Finally,the evaluation model of red soil drought index was established based on the characteristic parameters of dielectric spectroscopy.The error between the predicted value and the standard value was between± 1％.The model could effectively evaluate the degree of red soil drought degree to provide the reference indicators for regional agricultural drought investigation,assessment,and early warning in red soil.关键词
红壤/频域介电谱/特征参数/体积含水量/干旱指标Key words
red soil/frequency domain dielectric spectroscopy/characteristic parameter/volumetric water content/drought index分类
农业科技引用本文复制引用
王海军,徐兴倩,屈新,赵熹,王能龙,曹涵..基于介电频谱特征参数的红壤干旱指标评价研究[J].干旱地区农业研究,2024,42(1):261-269,9.基金项目
国家自然科学基金(42367025) （42367025）
云南省基础研究计划面上基金(202101AT070271) （202101AT070271）
云南省高层次人才培养支持计划"青年拔尖人才"专项(YNWR-QNBJ-2020-030) （YNWR-QNBJ-2020-030）
云南省教育厅科学研究基金(2023Y1017) （2023Y1017）
