前言林冠野外光谱测定的主要目的是获得可靠的统计数据,以便为用多波段数字资料对森林做精细的分类提供依据。为达此目的,须具备三个必要的条件:(1)各种林型的辐射数据之间,确实存在着有一定显著性的差异。(2)能从类比于传感器的角度,准确地测定这种辐射差异。(3)通过大气传输校正,将地面测定的辐射数据与同种地物象元的辐射水平建立定量关系。 Foreword The primary goal of canopy field spectrometry is to obtain reliable statistics to provide a basis for finely classifying forests using multi-band digital data. In order to achieve this goal, three necessary conditions must be met: (1) there are some significant differences between the radiation data of various forest types. (2) This radiation difference can be accurately measured from the analogy with the sensor. (3) Through the atmospheric transmission correction, the radiation data measured by the ground and the radiation level of the same kind of pixel are established quantitatively.