干旱胁迫对3种冷季型草坪草光谱反射率及生理特征的影响

为探讨高光谱分析技术在草坪草水分监测上的应用,以草地早熟禾、高羊茅、多年生黑麦草为试验材料,测定了干旱胁迫下3种冷季型草坪草生理指标及光谱反射率。结果表明:随着干旱胁迫程度的加深,供试草坪草叶片相对含水量和叶绿素含量显著下降(P0.05),丙二醛含量、脯氨酸含量及敏感波段的(550和760 nm)的光谱反射率显著上升(P0.05),3种草坪草抗旱性能的强弱顺序为:高羊茅多年生黑麦草草地早熟禾。3种草坪草敏感波段光谱反射率(R_(550 nm),R_(760 nm))及高光谱参数(Rg,R0,GNDVI)与生理指标间呈显著或极显著相关,以R_(550 nm)与生理指标间的相关系数绝对值最大。同时R_(550 nm)构建了供试草坪草生理指标的估测模型,经检验,模型估测值与实测值相关性达显著或极显著水平。

Study on spectral reflectance and physiological characteristics of three cool-season turfgrass under drought stress

To test the application of spectral analysis technology for water monitoring of turfgrass,the spec-tral reflectance and physiological indices of three turf grass under drought stress were measured,and the correla-tionship between spectral reflectance and physiological indices was analyzed.The results showed the leaf relative water and chlorophyll content decreased,and the MDA,proline content,spectral reflectance at the wave of 550 nm and 760 nm of three cool-season turfgrass increased significantly with the deepening of drought stress (P <0.05),and the sequence of drought tolerance of three cool-season turfgrass was tall fescue>perennial ryegrass>bluegrass.The correlationship between spectral reflectance (R5 50 ,R7 60 ),hyperspectral parameters (Rg,R0, GNDVI)and physiological indices was significant (P <0.05 or 0.01),and the coefficients were highest between spectral reflectance R5 50 and physiological indices.The monitoring estimation models of physiological indices were constructed based on spectral reflectance (R5 50 ).Upon testing,the correlationship between estimated and measured value was significant.