土壤组成与性质对近红外光谱检测土壤含水量的影响

Influence of Soil Constituent and Properties on NIRS Technology in Soil Water Monitoring

以湖北地区的红壤、黄棕壤和潮土为供试土壤,研究了外源添加黏土矿物(高岭石、水云母、针铁矿、蒙脱石、蛭石)含量、有机质含量和模拟土壤颗粒大小、土壤水稳性团聚体大小对近红外光谱检测土壤含水量的影响,并分别建立了相关模式方程。结果表明,土壤的光谱特性是土壤中多因子作用的综合结果,土壤组成与性质明显地影响着近红外光谱检测土壤水分时土壤光谱反射率的变化。在土壤中添加这些黏土矿物和有机质,其光谱反射率下降;在沙土、粉沙土范围内,土壤颗粒直径由大变小,其光谱反射率增大,但至<0.002 mm黏粒时,其反射率减小;土壤水稳性团聚体由大变小,其光谱反射率增大。

Based on red soil,yellow brown soil and alluvial soil in Hubei Province,the influence of soil clay mineral（kaolinite,hydromica,goethite,montmorillonit and vermiculite）content,organic matter content,soil particle size,soil water stable aggregate size on NIRS technology in soil water monitoring by adding soil constituent and modeling soil properties are studied.Therefore the relevant model equations are established.The results show that soil spectroscopy properties are the result of the influence of multi-factors.Soil constituent and properties affects greatly the reflectance change when the soil water is monitored by NIRS.The reflectance decreases as these clay minerals and organic matter content increase in soil;the reflectance increases as soil particle diameter decreases,but the reflectance decreases as soil particle diameter 0.002 mm clay in different soils;the reflectance increases as the soil aggregate diameter decreases.