轮台白杏叶片铁锰浓度光谱估算模型

摘要

建立基于光谱分析的轮台白杏叶片铁（Fe）、锰（M n）元素浓度估算模型，为快速建立轮台白杏树体微量营养元素诊断体系提供技术途经。采用U nispec-SC光谱仪测定土壤肥力存在显著差异条件下轮台白杏果实不同生育时期叶片的光谱反射率，通过分析叶片中Fe和M n元素浓度与 Rλ和 f′（Rλ）的相关性，筛选出光谱指示波段，并采用线性回归模型建立光谱估算模型以估算叶片 Fe和M n营养元素浓度。结果表明：轮台白杏果实不同生育时期叶片Fe元素的光谱敏感波段各不相同，果实坐果期和硬核期敏感波段分别为873和874 nm ，375和437 nm。果实成熟期敏感波段为836和837nm而果实收后期敏感波段为325和1054 nm ；轮台白杏果实四个生育时期M n元素的光谱敏感波段分别为913和1129 nm ，425和970 nm ，390和466 nm ，423和424 nm ；轮台白杏叶片Fe和M n元素浓度均与光谱反射率一阶微分 f′（Rλ）相关性最强，与之建立的线性光谱估算模型拟合度最高，且达到了显著或极显著水平。表明果实不同生育时期，轮台白杏叶片Fe和M n元素的光谱指示波段不同，可根据双波段 f′（Rλ）采用线性模型估算白杏叶片 Fe和M n元素浓度。%Aimed at providing technology for a rapid nutrition diagnosis system of micronutrients in A rmeniaca vulgaris cv . Luntaibaixing ,we established an element concentration estimation model for its foliar ferrum (Fe) and manganese (Mn) concen-tration based on spectrum analysis .The foliar spectrum reflectance at various phenological periods of fruit development under different soil fertility conditions was measured by Unispec-SC spectrometer .By analyzing the correlation of foliar Fe ,Mn con-centration at various phenological periods of fruit development , the spectrum reflectance Rλ and its first-order differential f′(Rλ) ,we filtered out its sensitive bands .And we established an element concentration estimation model for its foliar Fe and Mn at various phenological periods of fruit development with the linear regression model .The results showed that the spectral sensi-tive bands of foliar Fe in fruit setting period were 873 and 874 nm ,375 and 437 nm in fruit core-hardening period ,836 and 837 nm in maturity period and 325 and 1 054 nm in post-harvest period .However ,the spectral sensitive bands of Mn were 913 and 1 129 nm ,425 and 970 nm ,390 and 466 nm ,423 and 424 nm ,respectively .The Fe and Mn concentration of A .vulgaris cv . Luntaibaixing leaves were the most relevant to the first-order differential f′(Rλ) of its spectrum reflectance ,whose linear spec-trum estimation model fitting degree was the highest and reached to a significant or highly significant level .It showed that the spectral sensitive bands of Fe and Mn element varied with different phenological periods of fruit development .The spectrum esti-mation models for its foliar Fe and Mn concentration could be established with linear model according to its first-order differential f′(Rλ) .