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Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

Jia G, Yu X, Fan D, Jia J - PLoS ONE (2016)

Bottom Line: No correlation was found between the spatial pattern of soil conditions and that of trees.Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances.Large trees did not show systematic inhibition of the saplings.

View Article: PubMed Central - PubMed

Affiliation: Key Lab of Soil and Water Conservation and Desertification Combating, Ministry of Education, College of Soil and Water Conservation, Beijing Forestry University, Haidian District, Beijing, PR China.

ABSTRACT
Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r) functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono) and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined.

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Related in: MedlinePlus

Univariate analyses of trees of different DBH classes.Univariate functions L(r) (dotted lines) are shown with the simulation intervals (shadow areas). L: large (DBH = 1-15cm); M: middle (DBH = 15-30cm); S: small (DBH> = 30cm).
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pone.0152596.g004: Univariate analyses of trees of different DBH classes.Univariate functions L(r) (dotted lines) are shown with the simulation intervals (shadow areas). L: large (DBH = 1-15cm); M: middle (DBH = 15-30cm); S: small (DBH> = 30cm).

Mentions: Regardless of species, trees of different sizes were strongly aggregated at almost all distances (Fig 4). However, the aggregation decreased as the tree size increased. In the case of Acer, the aggregated pattern of small trees shifted to random when the medium trees were examined. Despite the significant correlation between size and height, this transition in spatial pattern was observed only among different height classes of Betula and Populus (Fig 5).


Mechanism Underlying the Spatial Pattern Formation of Dominant Tree Species in a Natural Secondary Forest.

Jia G, Yu X, Fan D, Jia J - PLoS ONE (2016)

Univariate analyses of trees of different DBH classes.Univariate functions L(r) (dotted lines) are shown with the simulation intervals (shadow areas). L: large (DBH = 1-15cm); M: middle (DBH = 15-30cm); S: small (DBH> = 30cm).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4814042&req=5

pone.0152596.g004: Univariate analyses of trees of different DBH classes.Univariate functions L(r) (dotted lines) are shown with the simulation intervals (shadow areas). L: large (DBH = 1-15cm); M: middle (DBH = 15-30cm); S: small (DBH> = 30cm).
Mentions: Regardless of species, trees of different sizes were strongly aggregated at almost all distances (Fig 4). However, the aggregation decreased as the tree size increased. In the case of Acer, the aggregated pattern of small trees shifted to random when the medium trees were examined. Despite the significant correlation between size and height, this transition in spatial pattern was observed only among different height classes of Betula and Populus (Fig 5).

Bottom Line: No correlation was found between the spatial pattern of soil conditions and that of trees.Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances.Large trees did not show systematic inhibition of the saplings.

View Article: PubMed Central - PubMed

Affiliation: Key Lab of Soil and Water Conservation and Desertification Combating, Ministry of Education, College of Soil and Water Conservation, Beijing Forestry University, Haidian District, Beijing, PR China.

ABSTRACT
Studying the spatial pattern of plant species may provide significant insights into processes and mechanisms that maintain stand stability. To better understand the dynamics of naturally regenerated secondary forests, univariate and bivariate Ripley's L(r) functions were employed to evaluate intra-/interspecific relationships of four dominant tree species (Populus davidiana, Betula platyphylla, Larix gmelinii and Acer mono) and to distinguish the underlying mechanism of spatial distribution. The results showed that the distribution of soil, water and nutrients was not fragmented but presented clear gradients. An overall aggregated distribution existed at most distances. No correlation was found between the spatial pattern of soil conditions and that of trees. Both positive and negative intra- and interspecific relationships were found between different DBH classes at various distances. Large trees did not show systematic inhibition of the saplings. By contrast, the inhibition intensified as the height differences increased between the compared pairs. Except for Larix, universal inhibition of saplings by upper layer trees occurred among other species, and this reflected the vertical competition for light. Therefore, we believe that competition for light rather than soil nutrients underlies the mechanism driving the formation of stand spatial pattern in the rocky mountainous areas examined.

Show MeSH
Related in: MedlinePlus