摘要
土壤粒径是影响土壤光谱的重要因素之一。为了探究土壤粒径与土壤光谱的关系,以山西省闻喜县的冬小麦麦田土壤为研究对象,分别获取7个土壤粒径(2,1,0.5,0.25,0.154,0.125,0.074 mm)及相应的土壤光谱,通过分析不同粒径条件下土壤光谱反射率、土壤粒径与土壤光谱的相关性,研究土壤粒径对土壤光谱的影响及土壤光谱与粒径的响应关系。结果表明,不同土壤粒径大小对土壤的光谱曲线的形状以及光谱特征位置没有明显的影响,但是随着土壤粒径的减小,土壤光谱反射率呈现不同幅度的升高;分析不同土壤粒径光谱反射率的平均变化率可知,小于0.154 mm的土壤粒径对土壤光谱反射率的影响最大,位于近红外波段区域;相关性结果表明,土壤粒径和光谱反射率之间具有较好的相关性,在波段2 100 nm附近的相关性达到最大,相关系数可达-0.74,表明该波段与土壤粒径具有重要的相关关系。研究结果可为光谱技术应用于土壤生理生化指标的定量分析提供一定的理论参考和实践探索。
Particle size is one of the main factors which affect the soil spectra. To explore the relationship between the soil particle size and the soil spectra, the soils at the field of winter wheat in Wenxi county were made as the object and the collected soil were grinded and sieved with seven particle sizes （2, 1, 0.5, 0.251 O. 154, O. 125, 0.074 mm）. The soil spectra corresponding with every soil particle size were obtained. The spectral reflectance under different soil particle sizes were compared, and the correlative relationship between the soil particle sizes and soil spectra were analyzed. The result showed that the soil particle size had no effect on the spectral trend and the position of spectral feature. However, the spectral reflectance increased with the decreasing of soil particle size. The soil particle size （less than 0.154 mm） obviously affected the spectral reflectance, especially for the spectral reflectance in the near-infrared region. Furthermore, it proved that the soil spectra were highly related to the particle size, and the correlation coefficient could reached to -0.74 at the wavelenth of 2 100 nm which verified to be important to particle size. The study will provide some theoretical reference and practical application on further monitoring the soil property using the hyperspectral technology.
出处
《山西农业科学》
2016年第9期1325-1327,1359,共4页
Journal of Shanxi Agricultural Sciences
基金
国家自然科学基金项目(31371572
31201168)
山西省科学技术发展计划项目(201603D221037-3)
山西省归国人员重点资助项目(2014-重点4)
关键词
土壤粒径
土壤光谱
光谱特性
soil particle size
soil spectroscopy
spectral character
