Seasonal differences in leaf-level physiology give lianas a competitive advantage over trees in a tropical seasonal forest

Authors

Zhi-Quan Cai, Chinese Academy of SciencesFollow
Stefan A. Schnitzer, Marquette UniversityFollow
Frans Bongers, Wageningen UniversityFollow

Document Type

Article

Language

eng

Publication Date

8-2009

Publisher

Springer

Source Publication

Oecologia

Source ISSN

0029-8549

Abstract

Lianas are an important component of most tropical forests, where they vary in abundance from high in seasonal forests to low in aseasonal forests. We tested the hypothesis that the physiological ability of lianas to fix carbon (and thus grow) during seasonal drought may confer a distinct advantage in seasonal tropical forests, which may explain pan-tropical liana distributions. We compared a range of leaf-level physiological attributes of 18 co-occurring liana and 16 tree species during the wet and dry seasons in a tropical seasonal forest in Xishuangbanna, China. We found that, during the wet season, lianas had significantly higher CO₂ assimilation per unit mass (A _mass), nitrogen concentration (N _mass), and δ¹³C values, and lower leaf mass per unit area (LMA) than trees, indicating that lianas have higher assimilation rates per unit leaf mass and higher integrated water-use efficiency (WUE), but lower leaf structural investments. Seasonal variation in CO₂ assimilation per unit area (A _area), phosphorus concentration per unit mass (P _mass), and photosynthetic N-use efficiency (PNUE), however, was significantly lower in lianas than in trees. For instance, mean tree A _area decreased by 30.1% from wet to dry season, compared with only 12.8% for lianas. In contrast, from the wet to dry season mean liana δ¹³C increased four times more than tree δ¹³C, with no reduction in PNUE, whereas trees had a significant reduction in PNUE. Lianas had higher A _mass than trees throughout the year, regardless of season. Collectively, our findings indicate that lianas fix more carbon and use water and nitrogen more efficiently than trees, particularly during seasonal drought, which may confer a competitive advantage to lianas during the dry season, and thus may explain their high relative abundance in seasonal tropical forests.

Comments

Accepted version. Oecologia, Vol. 161, No. 1 (August, 2009): 25-33. DOI. © 2009 Springer. Used with permission.

Stefan A. Schnitzer was affiliated with University of Wisconsin-Milwaukee and Smithsonian Tropical Research Institute at the time of publication.

Recommended Citation

Cai, Zhi-Quan; Schnitzer, Stefan A.; and Bongers, Frans, "Seasonal differences in leaf-level physiology give lianas a competitive advantage over trees in a tropical seasonal forest" (2009). Biological Sciences Faculty Research and Publications. 709.
https://epublications.marquette.edu/bio_fac/709