AUTHOR=Yang Junlong , Yu Jian , Wang Guangping , Li Xiaowei 

TITLE=Competition and density dependence in arid mountain forest stands: revealing the complex process from spatial patterns

JOURNAL=Frontiers in Forests and Global Change

VOLUME=Volume 7 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/forests-and-global-change/articles/10.3389/ffgc.2024.1354240

DOI=10.3389/ffgc.2024.1354240

ISSN=2624-893X

ABSTRACT=Understanding the spatial patterns and interaction of trees is crucial for exploring forest dynamics. However, limited research has explored the spatial pattern and interactions between adults and their offspring in arid mountain forest ecosystem.We investigated the spatial distribution and interaction of recruitment, survival and mortality at different size classes in P. davidiana forest in Luoshan Mountains (Ningxia, China), to gain insight into its stand dynamics. (1) The shift from an aggregated to random distribution as seedlings grew and developed into adult trees. (2)The adult trees exhibited strong positive and weak negative spatial associations with seedlings and saplings, respectively, with an increasing spatial scale, yet both stages underwent stark transitions from negative (1-15 m scales) to positive (> 20 m scale) associations. (3) Generally, the closer individuals were to each other, the greater negative impact of neighbors on an individual's size. (4)Additionally adult trees strongly increased the risk of seedling mortality across the spatial scale of 0-50 m. ( 5) Less live seedlings than dead ones around dead seedlings. There was a stronger aggregation of dead seedlings than live seedlings. And the density dependent mortality in our study rejected the random mortality hypothesis . In summary, these results suggest that a spatial separation occurs between dead and live seedlings of P. davidiana. Under adult trees, negative dependence plays an important role in the arid mountain forest recruitment. Our findings will contribute to the restoration and conservation of arid mountain forest, and providing a theoretical support for forest management.