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Local-scale drivers of tree survival in a temperate forest.

Wang X, Comita LS, Hao Z, Davies SJ, Ye J, Lin F, Yuan Z - PLoS ONE (2012)

Bottom Line: The effect of tree size on survival varied from strongly positive for small trees (1-20 cm dbh) and medium trees (20-40 cm dbh), to slightly negative for large trees (>40 cm dbh).Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species.Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning Province, People's Republic of China.

ABSTRACT
Tree survival plays a central role in forest ecosystems. Although many factors such as tree size, abiotic and biotic neighborhoods have been proposed as being important in explaining patterns of tree survival, their contributions are still subject to debate. We used generalized linear mixed models to examine the relative importance of tree size, local abiotic conditions and the density and identity of neighbors on tree survival in an old-growth temperate forest in northeastern China at three levels (community, guild and species). Tree size and both abiotic and biotic neighborhood variables influenced tree survival under current forest conditions, but their relative importance varied dramatically within and among the community, guild and species levels. Of the variables tested, tree size was typically the most important predictor of tree survival, followed by biotic and then abiotic variables. The effect of tree size on survival varied from strongly positive for small trees (1-20 cm dbh) and medium trees (20-40 cm dbh), to slightly negative for large trees (>40 cm dbh). Among the biotic factors, we found strong evidence for negative density and frequency dependence in this temperate forest, as indicated by negative effects of both total basal area of neighbors and the frequency of conspecific neighbors. Among the abiotic factors tested, soil nutrients tended to be more important in affecting tree survival than topographic variables. Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species. Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management.

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Related in: MedlinePlus

Standardized parameter estimates (±2 SE) of abiotic and biotic variables and size on tree survival for three shade-tolerant guilds in the Changbai temperate forest.Filled circles indicate significant effects (P<0.05).
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pone-0029469-g002: Standardized parameter estimates (±2 SE) of abiotic and biotic variables and size on tree survival for three shade-tolerant guilds in the Changbai temperate forest.Filled circles indicate significant effects (P<0.05).

Mentions: Among the three shade-tolerance guilds (light-demanding, mid-tolerant and shade-tolerant), there were several differences in the relative importance of factors effecting tree survival. For the light-demanding group, the model with the lowest AIC only included tree size and biotic factors. That model could not be statistically differentiated from the model with tree size and abiotic factors (i.e. the difference in AIC was <2; Table 1), but none of the individual abiotic variables analyzed had a detectable effect on tree survival (Figure 2). The model with tree size and biotic factors was the best fit for the mid-tolerant group, while the model with tree size, biotic and abiotic factors was the best fit for the shade-tolerant group. Similar to the community-level results, tree size had the strongest positive effect on tree survival and total basal area had a significant negative effect for all shade-tolerance groups. Frequency of neighboring conspecifics had a marginally significant negative effect for all three groups (light demanding: P = 0.056; mid-tolerant: P = 0.063; shade-tolerant: P = 0.059). None of the topographic factors had a significant effect, while soil factors (Soil PC1) significantly affected survival for the shade-tolerant group (Figure 2).


Local-scale drivers of tree survival in a temperate forest.

Wang X, Comita LS, Hao Z, Davies SJ, Ye J, Lin F, Yuan Z - PLoS ONE (2012)

Standardized parameter estimates (±2 SE) of abiotic and biotic variables and size on tree survival for three shade-tolerant guilds in the Changbai temperate forest.Filled circles indicate significant effects (P<0.05).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3278403&req=5

pone-0029469-g002: Standardized parameter estimates (±2 SE) of abiotic and biotic variables and size on tree survival for three shade-tolerant guilds in the Changbai temperate forest.Filled circles indicate significant effects (P<0.05).
Mentions: Among the three shade-tolerance guilds (light-demanding, mid-tolerant and shade-tolerant), there were several differences in the relative importance of factors effecting tree survival. For the light-demanding group, the model with the lowest AIC only included tree size and biotic factors. That model could not be statistically differentiated from the model with tree size and abiotic factors (i.e. the difference in AIC was <2; Table 1), but none of the individual abiotic variables analyzed had a detectable effect on tree survival (Figure 2). The model with tree size and biotic factors was the best fit for the mid-tolerant group, while the model with tree size, biotic and abiotic factors was the best fit for the shade-tolerant group. Similar to the community-level results, tree size had the strongest positive effect on tree survival and total basal area had a significant negative effect for all shade-tolerance groups. Frequency of neighboring conspecifics had a marginally significant negative effect for all three groups (light demanding: P = 0.056; mid-tolerant: P = 0.063; shade-tolerant: P = 0.059). None of the topographic factors had a significant effect, while soil factors (Soil PC1) significantly affected survival for the shade-tolerant group (Figure 2).

Bottom Line: The effect of tree size on survival varied from strongly positive for small trees (1-20 cm dbh) and medium trees (20-40 cm dbh), to slightly negative for large trees (>40 cm dbh).Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species.Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning Province, People's Republic of China.

ABSTRACT
Tree survival plays a central role in forest ecosystems. Although many factors such as tree size, abiotic and biotic neighborhoods have been proposed as being important in explaining patterns of tree survival, their contributions are still subject to debate. We used generalized linear mixed models to examine the relative importance of tree size, local abiotic conditions and the density and identity of neighbors on tree survival in an old-growth temperate forest in northeastern China at three levels (community, guild and species). Tree size and both abiotic and biotic neighborhood variables influenced tree survival under current forest conditions, but their relative importance varied dramatically within and among the community, guild and species levels. Of the variables tested, tree size was typically the most important predictor of tree survival, followed by biotic and then abiotic variables. The effect of tree size on survival varied from strongly positive for small trees (1-20 cm dbh) and medium trees (20-40 cm dbh), to slightly negative for large trees (>40 cm dbh). Among the biotic factors, we found strong evidence for negative density and frequency dependence in this temperate forest, as indicated by negative effects of both total basal area of neighbors and the frequency of conspecific neighbors. Among the abiotic factors tested, soil nutrients tended to be more important in affecting tree survival than topographic variables. Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species. Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management.

Show MeSH
Related in: MedlinePlus