青海祁连瑞香狼毒的光谱差异特征提取  

Extraction of spectral difference characteristics of Stellera chamaejasme in Qilian County of Qinghai Province,Northwest China

作　　者：程迪[1] 刘咏梅[1] 李京忠[1] 莫重辉[2] 

机构地区：[1]西北大学城市与环境学院,西安710127 [2]青海大学农牧学院,西宁810016

出　　处：《应用生态学报》2015年第8期2307-2313,共7页Chinese Journal of Applied Ecology

基　　金：农业部公益性行业(农业)专项(201203062);国家自然科学基金项目(41171225)资助

摘　　要：瑞香狼毒是分布在青海省高寒草甸的主要毒害草之一,近年来其迅速蔓延对当地畜牧业危害严重并使草地生态系统日趋退化.在海北州祁连县选取狼毒分布的典型退化草甸,采用2012—2014年狼毒盛花期获取的实测光谱数据,分析狼毒与牧草的光谱差异性.结果表明：在350-900 nm的可见光-近红外波段,狼毒顶花的光谱反射特征明显异于狼毒叶片和同期牧草等绿色背景,顶花与绿色背景的光谱反射率差异主要体现在红谷和蓝谷.随着盖度的增加,狼毒群落光谱反射率整体升高,在近红外反射峰处狼毒群落与牧草群落光谱反射率具有最大差值,且不同盖度狼毒群落之间的差异性最明显.顶花与绿色背景以及狼毒群落与牧草群落的一阶导数光谱差异均体现在黄边幅值和蓝边幅值.狼毒群落盖度与光谱特征参量的线性回归分析表明,红谷与狼毒群落盖度的相关性最好（R2=0.94）,反演狼毒群落盖度的精度最高.盛花期区分狼毒与牧草的主要光谱特征参量为红谷、蓝谷与近红外反射峰,其对应的红、蓝及近红外波段的组合可用于构建狼毒提取的敏感指数.Stellera chamaejasme is one of the main poisonous weeds distributed in alpine meadow of Qinghai Province. Rapid spreading of S. chamaejasme has done serious harm to local animal husbandry and caused continuous grassland ecosystem degradation. This paper focused on the spectral differences between S. chamaejasme and herbage,taking the typical degraded alpine meadow dominated by S. chamaejasme in Qilian County of Haibei Region as the test site and using the spectral measurements acquired in the full-blossom period of S. chamaejasme from 2012 to 2014. The results showed that the spectral behavior of flowers of S. chamaejasme differed significantly from green background that included leaves of S. chamaejasme and herbage within 350- 900 nm of VIS-NIR wavebands. The biggest reflectance difference between flowers of S. chamaejasme and green background was located in the red valley,followed by the blue valley. The reflectance of S. chamaejasme community increased with the rising of coverage,the biggest reflectance difference between S.chamaejasme and herbage communities lied in the near-infrared peak,and the best separability between S. chamaejasme communities with different coverage was also at the point. The difference of first derivative spectra between flowers of S. chamaejasme and green background located in amplitude of yellow edge was remarkable,followed by amplitude of blue edge,the same as differences between S. chamaejasme and herbage communities. Linear regression analysis between coverage of S. chamaejasme and spectral feature parameters showed best result for red valley（ R2= 0. 94）. Finally,the red valley,the blue valley and the near-infrared peak were proposed for discriminating S.chamaejasme from herbage in the full-blossom period of S. chamaejasme,and the combination of corresponding red,blue and near-infrared bands could be used to build sensitive indices for S. chamaejasme recognition.

关 键 词：高寒退化草甸 瑞香狼毒 牧草 盖度 光谱特征参量 

分 类 号：S812.6[农业科学—草业科学]