direct reflectance

例句：

1. 1. The sun's direct reflectance is the primary source of light for most ecosystems.
   太阳的直接反射率是大多数生态系统的主要光源。
2. 2. The scientist measured the indirect reflectance of the material to determine its properties.
   科学家测量了材料的间接反射率，以确定其性质。
3. 3.The diffuse reflectance of the surface was low, indicating that the material was absorbing more light.
   表面漫反射率低，表明材料吸收的光更多。