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Typhoon Disturbance Mediates Elevational Patterns of Forest Structure, but not Species Diversity, in Humid Monsoon Asia

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Abstract

Understanding factors controlling ecosystem structure and function is key to predicting the effects of climate change on vegetation distribution and carbon sequestration. Cyclones play a large role in structuring ecosystems and cyclone intensity is expected to increase on a warming planet. The effects of cyclones on broad-scale ecosystem patterns could be substantial but are poorly understood. This study assessed forest structure and biodiversity patterns across an elevation gradient (300–3000 m) in mountainous, humid forests of Taiwan, an island experiencing an average of 3–6 typhoons (regional name of cyclones) annually, and contrasted those patterns with a gradient within the Wuyi Mountains of China (500–2100 m), where the climate is similar to Taiwan but typhoon occurrence is rare and effects are generally minimal. In both Taiwan and the Wuyi Mountains, tree species richness and diversity decreased with increasing elevation. Tree size and stature decrease from low to high elevations in the typhoon-protected Wuyi Mountains. In contrast, the biomass and stature of forests in Taiwan increased from low to high elevations. The relationship between forest stature and climate was also contrasting in relation to typhoon disturbance in that we found decreasing tree height and basal area with increasing temperature in Taiwan, but not in the Wuyi Mountains. The more than twofold increase in tree height and biomass with increasing elevations reported here for subtropical humid forests of Taiwan is a unique pattern that highlights the potential role of cyclones in driving elevational patterns of forest structure. Climate change-induced alterations in tropical cyclone regimes may affect elevational patterns of forest structure and carbon sequestration in regions experiencing frequent cyclones.

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Acknowledgements

This research was supported in part by Grants from the National Science Council of Taiwan (98-2313-B-003-003, 99-2313-B-003-003, 100-2313-B-003-002). The authors have no conflict of interest. We thank Dr. Craig Martin for comments on previous versions of the manuscript. We thank Lienhuachi Research Center of Taiwan Forestry Research Institute, Aowanda National Forest Recreation Area, Highland Experimental Farm of National Taiwan University, and Endemic Species Research Institute of Taiwan for logistical support. We thank Julia Chapman for her help in proofreading and formatting the manuscript.

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Authors and Affiliations

  1. Department of Life Science, National Taiwan Normal University, No. 88, Section 4, DingChow Road, Taipei, 11677, Taiwan

    Chung-How Chi & Teng-Chiu Lin

  2. Department of Biology, The University of Dayton, 300 College Park, Dayton, Ohio, 45469-2320, USA

    Ryan W. McEwan

  3. Department of Geography, National Taiwan University, No. 1 Sec. 4, Roosevelt Road, Taipei, 10617, Taiwan

    Chung-Te Chang

  4. Department of Ecology, Peking University, 5 Yiheyuan Road, Yifu, Beijing, 100871, China

    Chengyang Zheng

  5. Department of Geography, Fujian Normal University, No. 8, Shangshan Road, Cangshan District, Fuzhou, Fujian, 250007, China

    Zhijie Yang

  6. Department of Life Science, Tunghai University, No. 1727, Section 4, Taiwan Boulevard, Taichung, 40704, Taiwan

    Jyh-Min Chiang

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  1. Chung-How Chi
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TCL, CHC, and CZ conceived and designed the study. CHC and CZ performed the field work. CTC, JMC, and TCL analyzed the data. CTC, JMC, and ZY contributed materials/analysis tools. TCL, RWM, and JMC wrote the paper.

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Chi, CH., McEwan, R.W., Chang, CT. et al. Typhoon Disturbance Mediates Elevational Patterns of Forest Structure, but not Species Diversity, in Humid Monsoon Asia. Ecosystems 18, 1410–1423 (2015). https://doi.org/10.1007/s10021-015-9908-3

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