北京百花山白桦次生林的结构与生产力  

THE STRUCTURE AND PRODUCTIVITY OF BETULA PLATYPHYLLA SUK. SECONDARY FOREST IN BAIHUA MOUNTAIN, BEIJING.

作　　者：罗菊春 

出　　处：《北京林业学院学报》1984年第4期8-19,共12页

摘　　要：百花山位于北京西南部,有着大面积的次生林。无论面积或立木蓄积,白桦林皆占有优势。群落的结构是较复杂的,其中混有13个伴生树种,16个下木种,50多个活地被物种。林下天然更新中等,但是没有发现针叶树苗。 白桦群落可以划分为五个类型,面积最大的厚土层的绣线菊白桦林具有最好的生境条件与生产力。 多数白桦林为Ⅳ龄级(31—40年生),但还保持着较高的年蓄积生长量,与较大的生长潜力,因此,目前不应该施工采伐。 中等密度的白桦林有着最高的年蓄积生长量。根据D—C_w以及H—C_w的相关关系,计算了理论密度,编制了经营密度表。Large area of Baihua Mt. in the south-west of Beijing is covered with woody stands of second growth. The dominant species of these stands is white birch (Betula platyphylla Suk.) occupying the largest area with the highest stocking volume. Composition of this secondary forest is rather complex, it is a mixed forest of 13 tree species with 16 woody species as undergrowth and about 50 species of different plants as living growth cover. Natural regeneration of the dominant tree species is infrequent and no seedlings of coniferous trees have been found on the ground.Five forest types may be recognized. The most significant one is the S praea-Betula type occurring on habitat with deep surface soil. Best soil fertility and high productivity are the favorable features of this type.Prevailing age of most trees is 30-40 years old ( Ⅳ th age Icass). High annual increment in stands of this age class gives them a high potentiality in future growth. It seems not wise enough to cut them down at this age. The highest annual volume growth is found in stands of middle density of stocking.A table for determination of theoretical stand density for management of this species is given, based on calculation of growing-space ration (DBH: Cw (erown diameter) and H (tree hight) : Cw) .

关 键 词：北京 百花山 白桦次生林 生产力 林分结构 

分 类 号：S758[农业科学—森林经理学] S792.153[农业科学—林学]