基于PHI影像敏感波段组合的冬小麦条锈病遥感监测研究

Monitoring Stripe Rust of Winter Wheat Using PHI Based on Sensitive Bands

利用ASD地面非成像光谱仪对不同严重度的冬小麦条锈病的冠层光谱反射率进行测定,同时调查病情指数。通过对地面实测的46组病情指数与相应的光谱反射率进行相关性分析,筛选出了小麦条锈病在350～1 500 nm的敏感波段。结合多时相的高光谱航空飞行遥感图像数据的特点和规律,最终选择红波段的620～718 nm与近红外波段的770～805 nm为条锈病在PHI影像上的敏感波段。并利用620～718 nm和770～805 nm的平均光谱反射率与相应的病情指数建立了多元线性回归模型:DI=19.241 R_1—2.207 R_2+12.274,验证结果表明,该模型的历史拟合度很好。并利用此模型最终在PHI影像上成功的实现了对冬小麦条锈病发生程度与发生范围的监测。

Forty six points representing different severity degree of stripe rust were established in winter wheat field. The canopy reflectance was collected by an ASD hand-held spectrometer at each point. Meanwhile, the diseases index was investigated. These data were used for the following analysis. Firstly, the relationships between diseases index and reflectance of bands in the range of 300-1 500 nm were analyzed. The sensitive bands were selected for stripe rust detecting. Secondly, considering the character of PHI image, red bands （620-718 nm） and near infrared bands （770-805 nm） were assigned as the best bands. Finally, the mean reflectance of red bands （620-718 nm） and near infrared bands （770-805 nm） was calculated respectively to construct the reverse model with the observed diseases indexes： DI=19. 241R1-2. 206 67 R2＋12. 274 4. With this model, the severity degree of stripe rust of winter wheat was monitored suceessfully in PHI image.