角规自1948年问世以来,已在世界各国广泛使用。现已由最初的简单杆式角规,发展为棱镜角规、林分速测镜等多能的光学测树仪器;测定项目由每公顷胸高断面积扩大到树高、株数、材积等多项因子;工作原理也由普通的数学解释发展为一种包括点抽样、线抽样的统计体系。因此,角规测树已成为当代森林调查、以至研究林木更新、造林、生态学的一种重要方法。 Angle gauge since its publication in 1948, has been widely used in all countries in the world. Now from the initial simple rod angle gauge, the development of the prism angle gauge, forest speed measuring microscope and other multi-energy optical tree measuring instrument; determination of the project by the chest height area per hectare expanded to the tree height, number of trees, volume, etc. Factor; the working principle is also developed from the common mathematical explanation to a statistical system including point sampling and line sampling. Therefore, the angle measurement tree has become a modern forest survey, as well as study of forest regeneration, afforestation, ecology is an important method.