基于模糊识别的苹果花期冠层钾素含量高光谱估测

Hyperspectral Estimation of Kalium Content in Apple Florescence Canopy Based on Fuzzy Recognition

依据2008年和2009年2年在栖霞试验区利用地物光谱仪ASD FieldSpec3测定的苹果花期冠层高光谱和实验室内测定的钾素含量数据,以冠层高光谱反射率及其11变换形式与钾素含量分别进行相关分析,以相关系数最大者为自变量,采用模糊识别算法,建立钾素含量估测模型;以2008年的检验样本对模型进行检验,并利用2009的独立试验数据对模型进行验证。结果表明,原始光谱反射率(R)及其倒数(1/R)、对数(lgR)、平方根(R1/2)与钾素含量的相关性较差,但它们的一阶微分和二阶微分与钾素含量之间的相关性明显增强;建立的钾素含量估测模型^y=11.344 5h+1.309 7的相关系数r为0.985 1,总均方根差RMSE为0.355 7,F统计量为3 085.6;24个检验样本实测值与估测值的平均相对误差为9.8%,估测精度为90.2%;2009年试验验证精度达到了83.3%。表明模型用于苹果花期冠层钾素含量的估测具有较高的稳定性,模型精度能满足生产上对苹果钾素含量估测的要求。

The objective of the present paper is fast and nondestructive estimate of kalium content using ASD FieldSpec3 spectrometer determined hyperspectral data in apple florescence canopy.According to detection of hyperspectral data of the apple florescence canopy and kalium content data at laboratory in Qixia city of experimental orchards in 2008 and 2009,the correlation analysis of hyperspectral reflectance and its eleven transforms with kalium content was proceeded.The biggest correlation coefficient as independent variable and the estimation model of kalium content were established based on fuzzy recognition algorithms.The model was tested by sample inspection in 2008 and verified by data in 2009.The results showed that the correlation is less for the original spectral reflectance（R） and its reciprocal（1/R）,logarithm（lgR）,square root（R1/2） and the kalium content,but it is enhanced obviously for their first derivative and second derivative.The correlation coefficient（r） of kalium content estimating model =11.344 5h＋1.309 7 is 0.985 1,the total root mean square difference（RMSE） is 0.355 7 and F statistics is 3 085.6.The average relative error of measured values and estimated values for 24 inspection sample is 9.8%,estimation accuracy is 90.2% and verification accuracy is 83.3% utilizing test data in 2009.It was showed that this model is more stable by estimating apple florescence canopy of kalium content and the model precision is able to meet the needs of production.