冬小麦冠层光谱红边特征分析

Red-edge characteristics of winter wheat canopy spectra

  • 摘要: 通过对不同N素营养水平冬小麦冠层光谱特性的田间试验研究,发现红边位移现象:在孕穗期前,红边随施N量增加向长波方向“红移”;孕穗期后“红移”现象基本消失,继而发生“蓝移”。红边参数中红边斜率(dλred)与叶片N累积量(TN.D)、叶绿素含量(CHL.T)、叶绿素密度(CHL.D)的相关关系通过显著性检验,红边面积(∑dλ680~760)和叶片全N含量(N%)的相关关系通过显著性检验,红边位置(λred)、红边斜率、红边面积与叶面积指数有着密切关系,均通过极显著性检验,一些红边参数可作为小麦农学参数估测的简便方法。

     

    Abstract: Winter wheat canopy spectral reflectance was field measured using spectrometer Field Spec at different nitrogen levels and time periods. Some red-edge parameters including wavelength (λred), amplitude (dλred) and red-edge apex area (∑dλ680~760)were analyzed for winter wheat leaf chlorophyll (CHL.T), leaf nitrogen content(N%), leaf area index(LAI), accumulated leaf nitrogen content(TN.D), etc. It is found that red-edge positions move to long wavebands till booting stage and then fall back to short bands after booting. A significant correlation is found between dλred and TN.D, CHL.T, and CHL.D. Similar relation exists between ∑dλ680~760 and N%. Red-edge parameters show strong correlation with LAI. It is thus concluded that some red-edge parameters form part of the best remote sensing descriptors.

     

/

返回文章
返回