无人机搭载多光谱相机监测松材线虫病的研究

Monitoring Bursaphelenchus xylophilus with Multispectrum Camera in UAV

分析黑松(Pinus thunbergii)感染松材线虫病(Bursaphelenchus xylophilus)与含水量及叶绿素a、b和类胡萝卜素含量的关系。结果表明,黑松感染松材线虫病与含水量和叶绿素含量呈明显线性相关,与类胡萝卜素含量相关性较小,含水量和叶绿素含量可作为黑松感染松材线虫病的监测指标。光谱曲线随着黑松感染松材线虫病的严重程度而改变。感病初期,蓝、红光波段吸收率下降,绿光、红外波段反射率也下降,并呈现红边向长波方向位移态势;感病后期,出现典型症状时,数值明显下降,甚至消失,整个反射光谱曲线呈现平缓现象。健康黑松和感病黑松的一阶导数在710 nm处变化明显。在提取感病多光谱数据信息时,一阶导数相对于叶绿素吸收比指数提取效果更好。

Relationships between Pinus thunbergii infected by Bursaphelenchus xylophilus and water content,contentsof chlorophyll a,b and carotenoid were analyzed.Results showed that disease had significant linear correlation withwater content and chlorophyll content,and weak correlation with carotenoid content.Water content and chlorophyllcontent of P.thunbergii could be used as monitoring indicators of B.xylophilus.Spectral curve changed with severityof P.thunbergii infected by B.xylophilus.In initial stage of disease,absorption rate of blue and red bands decreased,and reflectance of green and infrared bands also decreased,and a red edge moved to long wave direction.When diseasewas serious,value significantly decreased or even disappeard,and the whole reflection spectral curve presented agentle phenomenon.The first derivative of healthy and infected P.thunbergii changed obviously at 710 nm.Comparedwith ratio index of chlorophyll absorption,the first derivative was more effective in extracting disease informationfrom UAV multispectral data.