Abstract:

Leaf area index (LAI) provides structured quantitative information for material and energy cycling on plant canopy surface,and is an important parameter for estimating vegetation canopy function,and also one of the most important structural parameters in ecosystem.In this study,Beijing Xishan experimental forest farm was taken as the research area,and five typical stands in the study area were taken as the research object.The results showed that:(1) the leaf area index of different forest types in growing season was trees>herbaceous plants>shrubs,the average leaf area index of four tree types in growing season was ranked as Quercusvariabilis > Robiniapseudoacacia > Pinustabuliformis > Platycladusorientalis;(2) In the whole growing season,the leaf area index of the four tree stands showed the same trend of change,showing the trend of "increasing-stabilizing-decreasing";(3)the variation coefficient of the leaf area index of shrubs was higher than that of trees and herbaceous plants,and the variation coefficient of the 5 stands was Vitex negundo var.heterophylla > Quercusvariabilis > Robiniapseudoacacia > Platycladusorientalis> Pinustabuliformis;the purpose of the research is to provide reference for forestry management departments and data support for forest management.

Key words: Beijing mountain area, typical forests, Leaf Area Index (LAI), growing season, dynamic change