A Portable Spectropolarimeter for Field Crop Canopies: Distinguishing species and cultivars of fully developed canopies by polarized light
A Portable Spectropolarimeter for Field Crop Canopies: Distinguishing species and cultivars of fully developed canopies by polarized light
复制标题
用于大田作物冠层的便携式分光偏振仪：通过偏振光区分完全发育的冠层的物种和品种
DOI：
10.1626/pps.5.311
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发表时间：
2002
影响因子：
2.5
通讯作者：
Shigeo Akita
中科院分区：
文献类型：
--
作者：
M. Shibayama;Shigeo Akita
本文介绍了一种由可见光、近红外和短波红外(490-2200 nm)8个光谱段和旋转膜偏振器组成的光谱偏振仪，用于测量大田作物冠层反射光的反射率和偏振度。本文介绍了该仪器的设计、技术指标和初步野外试验结果。太阳天顶角和观测角以及相对于太阳位置的观测角对偏振的影响比反射率大得多。对于发育完全的红薯和大豆冠层，偏振度是比每个单波段反射率和基于反射率的植被指数(如归一化差异植被指数(NDVI))更好的冠层判别指标。
Abstract A spectropolarimeter equipped with eight spectral bands in the visible, near– and short–wave infrared ranges (490–2200 nm) as well as a rotary film polarizer has been developed for measuring the reflectance and degree of polarization of light reflected from field crop canopies. This paper describes the design and specification of the instrument and the results of preliminary field experiments. Solar and view zenith angles and view azimuth direction relative to the solar position had a much greater influence on polarization than reflectance. For fully developed sweet potato and soybean canopies, the degree of polarization was a better discriminator of the canopy than each single band reflectance and a reflectance–based vegetation index such as normalized difference vegetation index (NDVI).