Big-sized trees overrule remaining trees' attributes and species richness as determinants of aboveground biomass in tropical forests
© 2019 John Wiley & Sons Ltd.
| Veröffentlicht in: | Global change biology. - 1999. - 25(2019), 8 vom: 15. Aug., Seite 2810-2824 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2019
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| Zugriff auf das übergeordnete Werk: | Global change biology |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't big-crown trees biodiversity climate change large-diameter trees medium- and small-sized trees soil fertility tall-stature trees |
| Zusammenfassung: | © 2019 John Wiley & Sons Ltd. Large-diameter, tall-stature, and big-crown trees are the main stand structures of forests, generally contributing a large fraction of aboveground biomass, and hence play an important role in climate change mitigation strategies. Here, we hypothesized that the effects of large-diameter, tall-stature, and big-crown trees overrule the effects of species richness and remaining trees attributes on aboveground biomass in tropical forests (i.e., we term the "big-sized trees hypothesis"). Specifically, we assessed the importance of: (a) the "top 1% big-sized trees effect" relative to species richness; (b) the "99% remaining trees effect" relative to species richness; and (c) the "top 1% big-sized trees effect" relative to the "99% remaining trees effect" and species richness on aboveground biomass. Using environmental factor and forest inventory datasets from 712 tropical forest plots in Hainan Island of southern China, we tested several structural equation models for disentangling the relative effects of big-sized trees, remaining trees attributes, and species richness on aboveground biomass, while considering for the full (indirect effects only) and partial (direct and indirect effects) mediation effects of climatic and soil conditions, as well as interactions between species richness and trees attributes. We found that top 1% big-sized trees attributes strongly increased aboveground biomass (i.e., explained 55%-70% of the accounted variation) compared to species richness (2%-18%) and 99% remaining trees attributes (6%-10%). In addition, species richness increased aboveground biomass indirectly via increasing big-sized trees but via decreasing remaining trees. Hence, we show that the "big-sized trees effect" overrides the effects of remaining trees attributes and species richness on aboveground biomass in tropical forests. This study also indicates that big-sized trees may be more susceptible to atmospheric drought. We argue that the effects of big-sized trees on species richness and aboveground biomass should be tested for better understanding of the ecological mechanisms underlying forest functioning |
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| Beschreibung: | Date Completed 11.10.2019 Date Revised 11.10.2019 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1365-2486 |
| DOI: | 10.1111/gcb.14707 |