玉米主要生育期冠层反射光谱特征分析

Characteristic Analysis of Canopy Reflectance Spectrum during the Main Growth Period of Maize

在同一施肥水平下,选取3个不同品种的玉米植株,分别在玉米幼苗期、拔节期、吐丝期、灌浆期测定玉米的冠层高光谱反射率,分别对3个不同品种玉米的原始光谱反射率、光谱反射率一阶微分进行分析。结果表明:在拔节期和吐丝期,各品种玉米反射率差异较大,总体表现为富友968>先玉1225>吉单66;在拔节期、吐丝期,一阶微分导数曲线在680～760nm处,均发生了"红移"现象;在灌浆期,红边呈现"蓝移"现象,红边斜率减小。

Three different varieties of maize were selected to measure the canopy hyperspectral reflectance during the seedling stage, jointing stage, silking stage and filling stage under the same fertilization level. Their original spectral reflectances and first order differentials of the spectral reflectance were analyzed. The results showed that the reflectances had great differences at the jointing stage and silking stage, presenting the whole trend that Fuyou 968>Xianyu 1225 >Jidan66. At the jointing stage and silking stage, the first order differential derivative curve was at 680~760 nm with red-shift phenomenon. At the filling stage, the red edge displayed blue shift and the slope of the red edge was reduced.