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FOREST RESOURCES WANAGEMENT ›› 2022›› Issue (1): 8-17.doi: 10.13466/j.cnki.lyzygl.2022.01.002

• Scientific Research • Previous Articles     Next Articles

Autocorrelation Analysis of Quantitative Index of Stand Spatial Structure Based on Moran's I

QING Dongsheng1,2,3(), PENG Jinxiang2, LI Jianjun1(), DENG Qiaoling2, LIU Shuai1   

  1. 1. Central South University of Forestry Science and Technology,Changsha 410000,China
    2. Hunan Applied Technology University,Changde,Hunan 415000,China
    3. National Engineering Laboratory of Forestry Ecological Application Technology in South China,Changsha 410000,China
  • Received:2021-12-01 Revised:2021-12-29 Online:2022-02-28 Published:2022-03-31
  • Contact: LI Jianjun E-mail:673390302@qq.com;390033868@qq.com

Abstract:

In order to study the autocorrelation of spatial structure indexes between object trees and adjacent trees in stand spatial unit,the spatial logical relationship between object trees and adjacent trees was analyzed.Twenty five 20m×20m sample plots were set up in Daweishan Nature Reserve,Wuyunjie Nature Reserve and Lutou Forest Farm,the forest spatial unit based on Voronoi diagram was constructed,the adjacent trees of each object forest were determined,and the mixing degree,open ratio,DBH size ratio and competition index were selected as the quantitative indexes of forest spatial structure,and the values of each index were calculated. Finally,combined with the basic principle of global Moran's I index,the autocorrelation analysis scheme of stand spatial structure unit index was constructed to analyze the stand in the study sample plot.The results showed that the stand in the study area was a medium mixed forest,and the trees in this area were in a medium crowded state. There were great differences in DBH distribution between the object trees in the study area and the adjacent trees in its spatial unit,and the competition between trees was relatively obvious.From the perspective of spatial relationship,the mixing degree and open ratio of trees in the study area were positively correlated with their adjacent trees in space,and logically showed aggregation;The DBH size ratio and competition index of trees were negatively correlated with their adjacent trees in space,which was logically discrete. In addition,the spatial relationship between the trees in the survey area and their adjacent trees was mainly competition. The mixing degree and competition index of the trees in the stand may be the main spatial indicators leading to the heterogeneity between them and the surrounding adjacent trees.

Key words: stand spatial structure, stand spatial relationship, Moran's I index, spatial structure quantification, autocorrelation

CLC Number: