【摘要】 基于小麦田间试验,采用ASD光谱仪连接余弦接收器实测小麦冠层宽波段反照率,并同步取样测试小麦覆盖指数、干物质积累量、含氮量及绿度特征等指标,对小麦冠层宽波段反照率与小麦长势的关系进行分析。结果表明,冠层反照率与叶面积指数(LAI)间呈极显著正相关关系(P<0.01),拟合方程的决定系数为0.74,与NDVI、EVI间均呈显著的线性函数关系(P<0.05);冠层反照率与地上干物质积累量、叶茎含氮量间也均呈极显著正相关关系(P<0.01),拟合方程的决定系数分别为0.71、0.81和0.60。对于小麦叶片绿度特征,冠层反照率与其相关关系采用两段线性拟合效果较好,两个线性函数的决定系数分别为0.53、0.63。研究结果说明小麦冠层反照率与麦田覆盖特征关系密切,利用宽波段反照率监测小麦长势变化特征是可行的。更多还原

【Abstract】 The field experiment was conducted to analyze the relationship between wheat canopy broadband albedo and wheat growth status,using ASD Remote Cosine Receptor(RCR).Coverage index,dry matter,nitrogen content and SPAD were measured.The results showed that there was significantly positively correlation(r = 0.74,P < 0.01)between canopy albedo and the leaf area index(LAI).The canopy albedo was significantly correlation with NDVI and EVI,respectively(P < 0.05);Dry matter,nitrogen content in leaf and stem were markedly related to canopy albedo(P <0.01) and the determination coefficient were 0.71,0.81 and 0.60,respectively.Correlation between albedo and SPAD value was fitted by using piecewise linear function,and their R2 was 0.53 and 0.62,respectively.The results indicated that wheat canopy albedo was closely associated with crop growth status,and thus it was feasible to monitoring wheat growth characteristics by using the broadband albedo.更多还原