| 摘要: |
| [目的]探讨采用光谱分析手段估测果树N、P、K营养元素含量的精度及应用潜力.[方法]首先,对果树鲜叶的光谱反射率(Rλ)以及叶片全氮(TN)、全磷(TP)、全钾(TK)含量进行测定,并对各种元素含量与Rλ及其多种变式数据(1/Rλ、lg(1/Rλ)、d1Rλ、d2Rλ、d1[lg(1/Rλ)]、d2[lg(1/Rλ)]、lg(1/BNC)、f'(Rλ)、Dn)的相天性进行分析,找出与每种元素含量相关性最强的光谱数据形式;其次,采用逐步回归法,对每种元素含量和与其相关性最强的光谱数据形式进行回归分析,得到入选波长;最后,利用人选的波长,进行基于最小误差平方和的偏最小二乘回归建模.[结果]叶片TN、TK含量与波长间隔设为5 am的d1Rλ的相关性最强,TP含量与波长间隔设为9 nm的d1[lg(1/Rλ)]的相关性最强;利用人选的特征波长建立的估测模型均具有较好的线性趋势,R2均在0.8以上.[结论]光谱分析手段对果树N、P、K营养元素含量的估测精度较高,具有一定的应用潜力. |
| 关键词: 光谱分析 果树叶片 全氮 全磷 全钾 估测 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金? |
|
| Research on predicting the TN,TP,TK contents of fresh fruit tree leaves by Spectral Analysis with Red Fuji Apple tree as an example |
|
|
| Abstract: |
| 【Objective】 The research was expected to evaluate the possibility and application potential of spectral analysis on predicting nutritional element of fruit trees.【Method】 Firstly,we measure the specific reflectance (Rλ) of fruit tree fresh leaves and the leaves total nitrogen (TN),total phosphorus (TP),total potassium (TK) contents,and analyzed the statistical correlation between each element content and Rλ as well as its several transformations (1/Rλ,lg(1/Rλ),d1Rλ,d2Rλ,d1［lg(1/Rλ)］,d2［lg(1/Rλ)］,lg(1/BNC)，f′(Rλ)，Dn） within the wavelength range from 400 nm to 900 nm by factor analysis method,and discovered the spectral reflectance variant of the highest correlation coefficient.Subsequently,we carried on the regression analysis of each element content and the corresponding spectral reflectance variant of the highest correlation coefficient by stepwise regression method,and chose the eigenvalue wavelengths with which to carry on partial least squares regression modeling based on the least square error.【Result】 The results show that the correlation cofficient is the highest between the leaves TN or TK content and the first derivative of spectral reflectance with derivative gap=5 nm;the correlation coefficient is the highest between the leaves TP content and d1［lg(1/Rλ)］ with derivative gap=9 nm;the regression models established using the wavelengths selected by stepwise regression method when Sig(it’s a probability numerical higher than F detection value) is set to 0.02 and ramoval is set to 0.03 have the better linear trend,andR2values are higher than 0.8. 【Conclusion】 As a whole,the method of spectral analysis has some application potential to predict TN，TP，TK element of fruit trees. |
| Key words: spectral analysis fruit tree leaf TN TP TK predicting |
