不同粒径沙地表面双向反射特性研究

Bidirectional reflectance of sandy land surface with different particle sizes

由于自然环境遭到人为因素的破坏,我国沙地面积正在逐步扩大,确定沙地的性质与面积已经成为改善环境的重要的指示性信息.遥感技术以其特有的优势可以为沙地监测提供科学有效的信息.本文以不同粒径沙地表面为研究对象,测量其双向反射信息,分析粒径大小对沙地表面反射特性的影响;基于现有的模型对不同粒径大小沙地表面的反射信息进行计算,与实测信息进行对比.研究结果表明,粒径大小对沙地表面反射的反射分布特性有明显的影响;通过对比测量的反射信息与模型计算的反射信息发现,利用双向反射模型可以准确地计算出不同粒径沙地表面的反射信息.本研究不仅确定了粒径大小对反射信息的影响,也为遥感技术估算沙地表面粒径大小以及研究地表固有光学特性提供参考.

The area of sandy land is extending in China because the natural environment suffers the destruction by the human activity. The estimation of the properties and area of sandy land is an important indicative information for improving the environment. Remote sensing technique can provide scientific and effective data sources using its unique advantage. In this study, we measure the bidirectional reflectance information from sandy land surfaces with different particle sizes and analyze the effect of particle size on the reflection characteristics. Then, a comparison is performed between the measured reflectance and the reflectance of sandy land surface with different particle sizes which is computed based on existing model. The results show that the effect of particle size on the bidirectional reflectance distribution is apparent We also find that the bidirectional reflectance of sandy land surface with different particle sizes can be computed using the bidirectional reflectance model when the difference between measured reflection information and modeled reflection information is small. This study not only defines the effect of particle size on the reflectance from sandy land surface, but also provides valuable reference for estimating the particle size from sandy land surface using remote sensing technique and studying the intrinsic optical property of land surface.