我场天然次生林中,萌生阔叶混交林占有很大比重,而且又是急需抚育改造的对象。为了探索阔叶混交林适宜的抚育强度和改造方式,今春我场对椴杨等混交林分别设了四块固定标准地。 一、起始径阶的确定 是依据立木结构一般规律而确定的。以林分平均直径的0.4倍为最小直径,就为起始检尺径阶;林分平均直径的1.7倍为最大直径,即为最大检尺径阶。 Natural secondary forests in my field, a large part of the initiation of broad-leaved mixed forest, but also urgent need to temper the object of transformation. In order to explore the appropriate tending strength and transformation methods for broad-leaved mixed forests, we set up four fixed standards for the mixed forests of linden and poplar separately in spring and spring. First, the determination of the initial diameter is based on the general rule of standing timber structure. The average diameter of the forest 0.4 times the minimum diameter, as the initial test diameter step; average diameter of 1.7 times the maximum diameter of the forest, which is the largest diameter test step.