轮台白杏叶片氮磷钾含量光谱估算模型

Models for Estimating Foliar NPK Content of Armeniaca vulgaris 'Luntaibaixing' Using Spectral Reflectance

[目的]通过分析不同氮(N)、磷(P)、钾(K)施肥水平下轮台白杏果实不同生长发育阶段叶片氮、磷、钾含量与其光谱反射率的相关性,探寻用于轮台白杏叶片N、P、K含量估算的光谱敏感波段和模型,旨在为开发高效、适时、非破坏性的轮台白杏树体营养诊断技术提供方法。[方法]基于"3414"肥料效应田间试验,采用相关分析和回归分析。[结果]在轮台白杏果实膨大期、硬核期、着色期、成熟期,其叶片N素的光谱敏感波段分别为564～664、499～574和735～1 067、310～1 031、310～419和518～606 am,P素的光谱敏感波段分别为424～656、519～652、511～617、512～610 nm,K素的光谱敏感波段分别为425～701和721～1 113、475～733、500～721、539～673和719～l 058 nm。轮台白杏果实不同生长发育阶段叶片N、P、K含量与其光谱反射率或其衍生变量存在幂函数或指数函数关系。[结论]轮台白杏果实不同生长发育阶段叶片N、P、K素存在不同的光谱敏感波段,可根据光谱敏感波段的光谱反射率或其衍生变量利用幂函数或指数函数建立果实不同生长发育阶段叶片N、P、K含量光谱估算模型。

[ Objective ] Spectral sensitive bands and models used for estimating foliar NPK content were explored by analyzing correlation between foliar nitrogen （N） content, phosphorus （P） content, potassium （K） content and leaf spectral reflectance of Armeniaca vulgaris ＇ Luntaibaixing＇ at various phenological stages of fruit development under diverse NPK fertilization levels to provide approach for developing effective, timely and nondestructive nutrition diagnosis. [ Method] Based on ＂3414＂ fertilizer effect field experiments, using correlation analysis and regression analysis. [ Result] The spectral sensitive bands of foliar N, P, and K element were different in fruit enlargement stage, fruit hard core stage, fruit coloring stage and fruit maturity stage of A. vulgaris ＇ Luntaibaixing＇. The spectral sensitive bands of foliar N element at four phenological stages of fruit development were 564 -664,499 -574 and 735 - 1067, 310 - 1031,310 -419 and 518 -606 nm respectively. The spectral sensitive bands of foliar P element at four phenologieal stages of fruit development were 424 - 656, 519 - 652, 511 - 617 and 512 - 610 nm respectively. The spectral sensitive bands of foliar K element at four phenological stages of fruit development were 425 - 701 and 721 - 1113,475 - 733, 500 - 721, 539 - 673 and 719 - 1058 nm respectively. The relation of power function and exponential function existed between the foliar NPK content and the leaf spectral reflectance or its derived variables at four phenological stages of A. vulgaris ＇ Luntaibaixing＇ fruit development. [ Conclusion ] The spectral sensitive bands of N, P and K element were not the same at various phenological stages of A. vulgaris ＇ Luntaibaixing＇ fruit development. The models for estimating foliar NPK content of A. vulgaris ＇ Luntaibaixing＇ were able to be established with power function or exponential function according to spectral reflectance of the sensitive bands or its derived variables.