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从1948年毕特利希发表角规样地法(简称WZP)以来,在理论和实用方面都曾作过很多研究。1959年K.F.St(o|¨)hr和Prodan为了消除WZP的不均质误差曾提出不用固定视角而按每株林木确定视角来求算每公顷断面积的方法。1962年S.H.Spurr提出用于造林学及生态学研究的点密度测定法。角度通算法(angle Count method)和角度加算法(angle summation method)统称角度测定法(angle method)也可以称前者为定角测定法(Constant angle method),后者为界限角测定法(limited angle method)。角度通算法是各林木都有其胸径的一定倍数为直径的扩大园,而园内胸高断面积与每公顷断面积存在固
Since Bertherty published the Cape Geographic Method (WZP) in 1948, much research has been done both in theory and in practice. In 1959, K.F.St (o | ¨) hr and Prodan proposed methods of determining the area per hectare for each tree without a fixed perspective in order to eliminate inhomogeneous errors in WZP. 1962 S.H. Purpur proposed densitometry for afforestation and ecology. The angle count method and the angle summation method collectively referred to as the angle method may also be referred to as the constant angle method and the latter method as the angle of view method). Angle through algorithm is that each tree has a diameter of its diameter multiples of the expansion of the park, and the park area of breast height and cross-sectional area per hectare