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一、前言华北落叶松是华北山区造林的主要树种之一。它具有生长快,材质优良,干形通直,耐腐性强的特点,是珍贵的建筑用材。但是过去过分强调集中连片,没有充分注意适地适树,致使不少林分生长不良,发育不正常,病虫害多。为了严格按照自然规律办事,切实做到科学造林,达到速生丰产优质的目的,必须对立地质量进行评定。立地条件是林木生长的基础。由于不同树种对立地的要求各异,即立地条件适宜的林木生长迅速,单位面积产量就高;若立地条件不适宜林木生长就不好,成林不成
I. Introduction Larix principis-rupprechtii is one of the main tree species afforestation in the mountainous area of North China. It has fast growth, good quality, dry straight, corrosion-resistant features, is a precious timber for construction. However, in the past, excessive emphasis was placed on contiguous contiguous trees and insufficient attention was paid to appropriate tree planting. As a result, many stands did not grow well, did not develop properly and had many pests and diseases. In order to act in strict accordance with the laws of nature and effectively achieve the goal of afforestation by science and technology so as to achieve the goal of fast growing, high yield and quality, the quality of the site must be assessed. Site conditions are the basis for forest growth. Due to different tree species on the site of different requirements, that is, site conditions suitable for rapid growth of trees, yield per unit area is high; if the site conditions are not suitable for forest growth is not good, not a success