2017~2022年广东江门古兜山自然保护区森林群落变化特征

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中图分类号：Q948文献标识码：A

文章编号：1001-9499（2025）03-0028-07

AbstractIn 2O22，a second investigation was conducted on the plots in Gudoushan forest with atotal area of 3hm2 .Community dynamics were analyzed in terms of significant values， α diversity， β diversity，and community recruitment rate.The results show that after five years of natural recovery，the number of species，individuals and the average DBH of the three plots have all increased.The number of species in the 2022 GDS-A， GDS-B and GDS-C in 2022 was 136，120 and 138， increased by21，6 and 5 species as compared to 2017. The number of individuals with DBH≥1 cm in the three plots increased by 983，669，and 617， respectively. The three plots had similar mortality rates， all being approximately 0.02/y， with higher turnover and growth rate of GDS-A plots in Masson pine-broadleaved forests than the evergreen broadleaved forest GDS-B plot and China fir-broadleaved forest GDS-C plot， at 0.09/y and 0.07/y ，respectively. The decline of Masson pine population and the expansion of broad-leaved tree populations in the GDS-A plot conform to the pattern of forest succession of subtropical forest： from mixed forest to top vegetation type （evergreen broad-leaved forest）.The increase in species and individuals in the community has a direct impact on the α （204 diversity of the community，especially the rise in the Margalef richness index. The β diversity of GDS-A， GDS-B and GDS-C in 2022 was also increased as compared to 2017，indicating the increasing the amount of endemism within each community and the decreasing the similarity between communities. Most of dead individuals are at smaller DBH （1≤DBH≤ 5） ，indicating more intense competition among small saplings， namely，the negative density dependence （NDD）. The negative density dependence is beneficial for maintaining community diversity.

Key words community dynamics; community diversity; forest succession; diameter class

森林是天然的物种基因库，碳贮库、蓄水库和能源库，对维系整个地球的生态平衡起着至关重要的作用[1]。（剩余9189字）