Real-Time Analysis of Soil Moisture, Soil Organic Matter, and Soil Total Nitrogen with NIR Spectra
SUN Jian-ying1,LI Min-zan1*,ZHENG Li-hua1,HU Yong-guang1, 2,ZHANG Xi-jie1
1. Key Laboratory of MOE on Modern Precision Agriculture System Integration Research, China Agricultural University, Beijing 100083, China 2. School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China
Abstract：The grey-brown alluvial soil in northern china was selected as research object, and the feasibility and possibility of real-time analyzing soil parameter with NIR spectroscopic techniques were explored. One hundred fifty samples were collected from a winter wheat farm. NIR absorbance spectra were rapidly measured under their original conditions by a Nicolet Antaris FT-NIR analyzer. Three soil parameters, namely soil moisture, SOM (soil organic mater) and TN (total nitrogen) content, were analyzed. For soil moisture content, a linear regression model was available, using 1 920 nm wavelength with correlation coefficient of 0.937, so that the results obtained could be directly used to real-time evaluate soil moisture. SOM content and TN content were estimated with a multiple linear regression model, 1 870 and 1 378 nm wavelengths were selected in the SOM estimate model, and 2 262 and 1 888 nm wavelengths were selected in the TN estimate model. The results showed that soil SOM and TN contents can be evaluated by using NIR absorbance spectra of soil samples.
Key words：NIR spectroscopy;Chemometrics;Soil moisture;Soil organic matter;Soil total nitrogen
