近红外光谱技术快速预测泡桐活立木年轮密度

应用近红外光谱分析技术主要对兰考泡桐活立木年轮密度进行了研究。取样时采用无损的方式，即不伐木，只从样木胸径处钻取直径为5 mm的木芯;用近红外光谱仪采用自动进级式采集样品光谱，波谱范围为350～2 500 nm;密度值采用水银体积仪测量;校正模型和预测模型建立与分析采用偏最小二乘和完全交互验证法。研究结果表明，中径级和大径级泡桐所选年轮数与近红外光谱值之间均存在很好的相关关系，预测模型相关系数分别达0.88和0.91;中径极的泡桐年轮密度与近红外光谱的校正模型和预测模型相关系数分别达到0.90和0.83，校正标准误差(SEC)和预测标准误差(SEP)分别为0.012和0.016。由此可见，该法可简单、快速、无损的预测中径级即接近采伐龄泡桐活立木的年轮密度。

Rapid Prediction of Annual Ring Density of Paulownia elongate Standing Tress Using Near Infrared Spectroscopy

Rapid prediction of annual ring density of Paulownia elongate standing trees using near infrared spectroscopy was studied.It was non-destructive to collect the samples for trees,that is,the wood cores 5 mm in diameter were unthreaded at the breast height of standing trees instead of fallen trees.Then the spectra data were collected by autoscan method of NIR.The annual ring density was determined by mercury immersion.And the models were made and analyzed by the partial least square(PLS) and full cross validation in the 350-2 500 nm wavelength range.The results showed that high coefficients were obtained between the annual ring and the NIR fitted data.The correlation coefficient of prediction model was 0.88 and 0.91 in the middle diameter and bigger diameter,respectively.Moreover,high coefficients of correlation were also obtained between annual ring density laboratory-determined and the NIR fitted data in the middle diameter of Paulownia elongate standing trees,the correlation coefficient of calibration model and prediction model were 0.90 and 0.83,and the standard errors of calibration(SEC) and standard errors of prediction(SEP) were 0.012 and 0.016,respectively.The method can simply,rapidly and non-destructively estimate the annual ring density of the Paulownia elongate standing trees close to the cutting age.