基于高光谱数据的土壤有机质含量预测研究

Study on Soil Organic Matter Content Estimated Model By Hyperspectral Remote Sensing Data

【目的】快速、有效、非接触、非破坏性地提取土壤有机质含量信息。探索新疆绿洲农区如何应用高光谱遥感技术分析、模拟、评价、预测土壤有机质含量,促进高光谱分辨率遥感技术在农田土壤遥感诊断、作物科学种植、水肥分区管理、田间农情监测中的应用,为新疆实施精准农业提供科学理论参考。【方法】利用高光谱遥感技术提取土壤有机质含量信息的研究,采用美国ASD Field Spec Pro VNIR 2500型光谱辐射仪获取田间土壤不同有机质含量信息的高光谱反射率;通过光谱分析技术,运用各种土壤反射率数学变换形式,找出最具代表性的敏感波段,揭示土壤有机质含量与其光谱成因机理之间的内在联系。【结果】基于NDI预测土壤有机质含量的估算模型中以一元三次函数模型(Y_(SOM)=-4E+07X_(NDI)~3+2E+06XN_(NDI)~2-21 338X_(NDI)+110.44,R^2=0.7132)为最优,指数函数模型次之。【结论】基于归一化光谱指数NDI可以较好的估算土壤有机质含量,利用统计方法建立的经验模型,简单实用,将对特定区域、特定土壤的预测有较好的效果。

[Objective] Fasy,effective,non-contact,non-destructive extraction of soil organic matter content information.[Method] This paper focuses on the monitoring of agricultural soil organic matter content with hyperspectral remote sensing,obtaining the hyperspectral reflectance information of soil without contact and destruction with the application of ASD Field Spec Pro VNIR 2500 Spectrum radiometer.This paper also reveals the physical components of soil and the internal relation of its spectrum caused by using spectral analysis technology and various forms of soil reflectance mathematical transformation to identify-the most representative sensitive waveband.[Result] NDI-based estimates of soil organic matter content prediction model with a cubic function model （YSOM =-4E ＋07XNDI^3 ＋2E ＋ 06XNDI^2-21 338XNDI ＋ 110.44,R^2 =0.713 2） as the best,followed by an exponential function model.[Conclusion] Studies showed that the application of hyperspectral remote sensing technology in terms of analysis,simulation,evaluation and prediction of soil characteristic parameters promoted the usage of hyperspectral remote sensing technology in the process of remote sensing diagnosis of farmland soil,which offered technical support in space distribution monitoring and the management of water and fertilization.Meanwhile the course of quantitative evaluation researeh was promoted and the application of remote sensing technology in scientific crop plantation and crop condition monitoring realized.This,therefroe,provided precision agriculture in Xinjiang with scientific evidence.