Structural Characteristics of Quercus mongolica Natural Forest Stands in the Northern Hebei Mountain Area
The study focuses on the natural Quercus mongolica forest in Huangyangshan National Forest Park,Zhuolu County,Zhangjiakou City,Hebei Province.It analyzes the non-spatial structure(tree species composition,diameter class struc-ture,tree height structure)and spatial structure(uniform angle index,neighborhood comparison,traditional mingling)characteristics of the forest stand.A comprehensive evaluation of the spatial structure of the stand was conducted using the square mean index(FSS).The results showed that the overall diameter class of the Q.mongolica population is mainly con-centrated in the 7 to 15 cm diameter class,with the majority of trees having heights ranging from 8.0 to 9.9 m,primarily occupying the mid-layer of the stand.The average uniform angle index of the stand as a whole was 0.550,exhibiting a clus-tered distribution,while plots 1,4,and 12 show a random distribution.The average neighborhood comparison of the whole stand was 0.512,indicating poor growth dominance among the trees.The average size ratio of Q.mongolica is between 0.250 and 0.500,suggesting a certain degree of growth dominance.The average mingling of the whole stand was 0.459,re-flecting a low level of mixing.The average mingling of the Q.mongolica was 0.310,falling within the weak to moderate mixing range,indicating a low degree of mixing and a relatively weak degree of spatial isolation.The overall FSS of the stand was 0.176,suggesting a deviation in the spatial structure of the stand.The neighborhood comparison is a primary in-dicator affecting the quality of the spatial structure of the stand.Enhancing tree growth dominance is the primary direction for optimizing the stand structure of Q.mongolica natural forests in the northern Hebei mountains and improving stand qual-ity.Additionally,it is essential to increase the degree of mixing while considering the rationality of the horizontal distribu-tion pattern.
Quercus mongolicaDiameter class structureTree height structureStand structureSpatial structure evaluation
万方数据
维普
