室内几何测试条件对土壤高光谱数据离散性的影响

Effect of geometric conditions on soil hyperspectral data scatter characteristic in laboratory test

利用方差分析方法,研究了光源照射角度、探头距离、光源距离3个几何测试条件对室内土壤高光谱数据离散性的影响.结果表明,探头距离对室内高光谱样本曲线的离散性影响不明显,而光源照射角度、光源距离对室内高光谱样本曲线离散性影响的显著性与选取的研究波段范围有关,除B1波段(400～900nm)外,都达到了极显著水平.在该试验研究条件下,15°的光源照射角度、15cm的探头距离和30cm的光源照射距离是较理想的室内测试几何条件组合.

The scatter characteristic of soil hyperspectrals is studied by variance analysis of geometric conditions, i.e., the angle of the beam, the distance between sensor and soil surface, and the distance between lamp and soil surface in laboratory test. The results show that the effect of the distance between sensor and soil surface on soil hyperspectral scatter characteristic is not significant, while the angle of the beam and the distance between lamp and soil surface have most significant effect on soil hyperspectral scatter characteristic, except B1 (400-900 nm) of the selected bands. And 15°, 15 cm, and 30 cm are recommended as the optimal values of beam angle, sensor distance, and lamp distance.