Abstract: Tall fescue plants (Festuca arundinacea Schreb.) under different growth conditions were used as the experiment material. Initially, spectral reflection indices of leaves and SPAD (Soil Plant Analysis Development) value were measured. Next, the relationship between SPAD value and spectral data were analyzed using multivariate statistical methods such as correlations and regressions. Finally, the relationship between the red edge parameters, vegetation index, derivative spectra extracted from spectral data and SPAD value were analyzed. Results showed that three spectral indices of the red edge position, NDVI, and the average derivative spectral data of 695~715 nm, had a favorable correlation with SPAD value and the correlation coefficients were 0.906, 0.842 and 0.826. Determination coefficients of establishing linear regression model were 0.820, 0.709 and 0.681, respectively. The spectral characteristics of tall fescue leaves had close correlation to pigment contents of leaves and the structure of mesophyll cells, but were independent to growth environment. SPAD value could be good inverted by red edge position, NDVI and derivative spectra. The edge position most accurately estimated SPAD value of tall fescue leaf, next was NDVI index, least is the derivative spectra index. Results provided a theoretical basis for inverting chlorophyll information of tall fescue growth period using hyperspectral remote sensing technology while analyzing photosynthesis and carbon metabolism ability.

Key words: Tall fescue, SPAD value, Red edge position, NDVI, Derivative spectra

摘要： 以不同生存环境下抽穗期的高羊茅(Festuca arundinacea Schreb.)为材料,测定叶片的光谱反射率和SPAD(soil plant analysis development,土壤-植物分析模式)值,采用相关、回归等多元统计方法分析叶片的SPAD值与光谱数据之间的关系;从光谱数据中提取红边参数、植被指数和微分光谱分别与SPAD值进行分析。结果表明:红边位置、NDVI和695~715 nm之间的平均微分光谱数据与SPAD值均具有很好的相关性,相关系数分别为0.906,0.842和0.826,建立的一元线性回归模型确定系数分别为0.820,0.709和0.681。高羊茅叶片的光谱特征与叶片中色素含量和叶肉细胞的结构密切相关,与其生存的环境条件无关;红边位置、NDVI和微分光谱均可以较好的反演SPAD值。相比而言,红边位置预测高羊茅叶片的SPAD值最为精确,NDVI次之,微分光谱最差。试验结果为利用高光谱遥感信息反演高羊茅抽穗期的叶绿素含量,进而分析其光合作用能力、碳代谢能力提供了理论依据。

关键词: 高羊茅, SPAD值, 红边位置, NDVI, 微分光谱