倒伏胁迫下冬小麦冠层光谱及红边特征

Canopy Spectral and Red Edge Characteristics of Winter Wheat under Lodging Stress

倒伏已成为影响小麦减产的主要因素之一,实时监测倒伏胁迫对小麦生长具有重要意义。通过人工模拟不同倒伏级别处理,利用光谱观测数据,分析了倒伏冬小麦光谱和红边参数变化特征。结果表明,倒伏小麦冠层光谱反射率较正常小麦整体增高,近红外波段比可见光波段增加明显,且倒伏级别越大反射率越高,表明冬小麦受倒伏胁迫后,冠层光谱对其响应敏感;倒伏小麦红边位置发生蓝移,红边幅值和红边面积则呈增大趋势。因此,可利用高光谱技术实现对冬小麦倒伏的实时监测。

Lodging had become one of the main factors which affected yield of winter wheat. The influence of lodging stress on spectrum red edge parameter was studied, basing on the field spectrum data from artificial simulated treatment of different lodging grade. The results showed that ladging of wheat canopy spectral reflectance was higher than the normal growth wheat. The reflectance of infrared band obviously higher than the visible band, and the reflectance was higher when the lodging grade was greater. It showed that canopy spectral responded sensitively to lodging stress of winter wheat. The red edge position showed ＂blue shift＂, and the red edge peak and area increased with the increased lodging stress level. So the lodging wheat could be monitored based on hyperspectral technology.