树干解析是测树学的基础技术,在森林生物量和生产力的测算上起着不可替代的作用。传统树干解析树木直径的测定方法是测量每个圆盘东西、南北两条直径线上每年(或龄阶)的直径,取两个方向同一年(或龄阶)直径的平均数作为测定结果。由于横断面为绝对圆形的树干很少,且髓心常常偏倚,使用传统方法测量的年轮直径往往小于真实直径,造成树木材积与生物量的低估。本研究对传统树干解析圆盘年轮的测定方法进行了改进,提出了不通过髓心的树木圆盘几何直径测定法,并制定了测定规则,以期减少个体测定差异,使测量值最大限度地接近真实值。使用不同方法对圆盘的年轮直径进行了测定,通过比较圆形度、逼近度指数,证明了本方法较传统方法更为准确。本方法原理简明,易于操作,具有较强的实用性,对于提高森林蓄积量和生物量的估算精度具有重要意义。 Tree trunk analysis is the basic technology of tree measurement, which plays an irreplaceable role in the measurement of forest biomass and productivity. Traditional tree trunk tree diameter determination method is to measure each disc, the north-south diameter of each line (or age) of the diameter, take the two directions in the same year (or age) diameter as the average measurement results. Because of the few round trunks that are absolutely circular in cross section and the often biased pith, the diameter of annual rings measured using conventional methods tends to be smaller than the true diameter, resulting in underestimation of tree volume and biomass. In this study, we improved the method of measuring the trunks of the traditional trunks, proposed the method of determining the geometric diameter of the trees without passing through the pith, and established the rules of measurement to reduce the individual differences in measurement so as to maximize the measurement value Close to the true value. The diameter of the ring was measured by different methods. By comparing the circularity and the approximation index, the method is proved to be more accurate than the traditional method. The method has the advantages of simple principle, easy operation and strong practicability, and is of great significance for improving the estimation accuracy of forest volume and biomass.