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自毕特利希(1947)首创利用角规测定林分单位胸高断面积以后,角规测树(水平点抽样)便很快发展成为一个独立的体系。由于其具有简便易行和效率高等优点,已经在各类森林调查及森林连续清查中广泛应用。但是也正由于其抽取样木株数少,用于估测森林资源的动态变化时精度往往较低。如何利用点抽样复查资料来合理估计林分生长量,国内外学者已经作过不少研究。最近,宋新民、徐祯祥提出了“潜在计数值法”。不失为一种有益的探索,但笔者认为该法实有值得商榷之处。
Since Bertelich (1947) pioneered the use of angle gauges to determine the thoracic and plinth area of forest stands, the angle gauge tree (horizontal spot sampling) soon developed into an independent system. Because of its simplicity and high efficiency, it has been widely used in various forest surveys and continuous forest inventory. However, due to the small number of sampled wood samples, the accuracy for estimating the dynamic changes of forest resources is often low. How to use the point sampling data to estimate the reasonable growth of stand, domestic and foreign scholars have done a lot of research. Recently, Song Xinmin, Xu Zhenxiang put forward the “potential counting method.” After all, it is a useful exploration, but I think the law is really debatable.