基于峰谷分析算法用针刺仪测定树木年龄的可行性分析

目的 介绍峰谷分析算法在树木针刺仪抗钻阻力数据中的应用，推进微损测定树木年龄方法的研究进程。 方法 以吉林省汪清县林业局金沟岭林场天然林中红松、冷杉为研究对象，钻取树木生长芯，同时使用针刺仪获取104组抗钻阻力数据。利用峰谷分析算法，根据树芯的实测年龄选定恰当的阈值Det，记录抗钻阻力的峰和谷的个数为估算的树木年轮数。 结果 根据树芯的实测年龄选定阈值后，利用峰谷分析算法估计树木年龄与实际年龄很接近。该算法估计年龄平均绝对误差是−2，范围在−5年至5年之间，平均相对误差为−2.69%，范围在−6.73%至6.73%之间。经过成对数据t检验得到t值为1.31，说明该算法估计树木年龄均值与真实年龄均值之间无显著差异。 结论 峰谷分析算法应用于针刺仪抗钻阻力序列来估计树木年龄是可行的，确定存在恰当的阈值使针刺仪估计树木年龄精度很高，阈值的选择依据是下一步研究的重点内容。

Feasibility Analysis of Tree Age Estimation Algorithm Using Resistograph Based on Peak-valley Analysis

Objective To study the application of Peak-valley analysis algorithm in the Resistograph drilling resistance sequence so as to promote the research on quasi-nondistructive tree age estimation. Method The increment cores and 104 groups Resistograph drilling resistance data were collected from Pinus koraiensis and Abies fabri in Jingouling Forest Farm, Wangqing Forestry Bureau, Jilin Province of northeastern China. The appropriate threshold value was selected according to the tree real age and the Peak-valley analysis algorithm was used to record the number of peaks and valleys of drilling resistance data as the estimation of tree age. Result The tree ages were estimated by the peak-valley analysis with the selected threshold value (Det), and the results showed that the data are close to the real tree age, with mean absolute error as −2 years, ranging from −5 to 5 years, and the mean relative error as −2.69%, ranging from −6.73% to 6.73%. Paired data t-test was carried out with t-value of 1.31, indicating that there is no significant difference between estimated tree age estimated by the method of peak-valley analysis and the real mean tree age. Conclusion The application of the drill resistance sequence on the tree age with peak-valley analysis algorithm is proved to be feasible. The appropriate threshold value is the key to guarantee the accuracy of tree age estimation by Resistograph, therefore it is the main part for further research.