Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-26T20:03:18.320Z Has data issue: false hasContentIssue false

Differential plant damage due to litterfall in palm-dominated forest stands in a Central Pacific atoll

Published online by Cambridge University Press:  13 March 2014

Hillary S. Young*
Affiliation:
Department of Biology, Stanford University, 371 Serra Mall, Stanford CA, 94305, USA Division of Vertebrate Zoology, Smithsonian Institution, PO Box 37012, MRC 108, Washington DC, 20013, USA
Douglas J. McCauley
Affiliation:
Hopkins Marine Station, Stanford University, 120 Oceanview Blvd, Pacific Grove, CA 93950, USA
Amanda Pollock
Affiliation:
US Fish and Wildlife Service, Honolulu HI, USA
Rodolfo Dirzo
Affiliation:
Department of Biology, Stanford University, 371 Serra Mall, Stanford CA, 94305, USA
*
1 Corresponding author. Email: hyoung@fas.harvard.edu

Abstract:

High densities of palms are common in many tropical forests. In some cases, the dominance of palms has been associated with a depauperate understorey and high rates of native seedling mortality. A variety of different potential mechanisms has been suggested to explain the sustained palm dominance in the understorey and canopy of these forests. Working in a Cocos nucifera-dominated wet tropical forest at Palmyra Atoll in the central Pacific, we examine how litterfall from this pantropical, and economically important palm, impacts seedling survival. We compare rates of litterfall, and rates of litterfall-associated damage, between forest stands dominated by C. nucifera (coconut palm) and forest stands with low abundance of C. nucifera. To assess litterfall damage we survey damage to both artificial seedlings (n = 711), outplanted real seedlings of two species (with and without protection via caging; n = 204), and standing rates of litterfall damage. We find that rates of large-litterfall damage were an average of five times higher in sites with high densities of C. nucifera. Associated with these increases we observe that levels of physical damage to artificial model seedlings caused by litterfall over a 4-mo period increased from 4.9% in sites with low abundance of C. nucifera to 16.1% in sites with high abundance of C. nucifera. Extrapolated to annual rates, litterfall damage of this magnitude exceeds the average levels observed in other published studies. Living native seedlings also showed more than 300% higher levels of mortality in forest stands with high densities of C. nucifera, a difference that was greatly reduced when protected by caging from litterfall. In contrast, uncaged C. nucifera seedlings actually had slightly higher survivorship in habitats dominated by conspecifics. We suggest that litterfall damage may be an important mechanism by which this tropical palm reaches and maintains near monodominance in many coastal and insular habitats.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

2

Current address: Department of Ecology, Evolution, and Marine Biology, University of California Santa Barbara, CA, 93106, USA

References

LITERATURE CITED

AGUIAR, A. V. & TABARELLI, M. 2010. Edge effects and seedling bank depletion: the role played by the early successional palm Attalea oleifera (Arecaceae) in the Atlantic forest. Biotropica 42:158166.CrossRefGoogle Scholar
AIDE, T. 1987. Limbfalls: a major cause of sapling mortality for tropical forest plants. Biotropica 19:284285.Google Scholar
AGUIRRE, A., GUEVARA, R. E. & DIRZO, R. 2011. Effects of forest fragmentation on assemblages of pollinators and floral visitors to male- and female-phase inflorescences of Astrocaryum mexicanum (Arecaceae) in a Mexican rain forest. Journal of Tropical Ecology 27:2533.Google Scholar
ALVAREZ-CLARE, S. & KITAJIMA, K. 2009. Susceptibility of tree seedlings to biotic and abiotic hazards in the understory of a moist tropical forest in Panama. Biotropica 41:4756.Google Scholar
CLARK, D. & CLARK, D. 1989. The role of physical damage in the seedling mortality regime of a Neotropical rain forest. Oikos 55:225230.Google Scholar
CLARK, D. & CLARK, D. 1991. The impact of physical damage on canopy tree regeneration in tropical rain forest. Journal of Ecology 79:447457.Google Scholar
DENSLOW, J. S. & GUZMÁN, G. 2000. Variation in stand structure, light and seedling abundance across a tropical moist forest chronosequence, Panama. Journal of Vegetation Science 11:201212.Google Scholar
DRAKE, D. & PRATT, L. 2001. Seedling mortality in Hawaiian rain forest: the role of small-scale physical disturbance. Biotropica 33:319323.Google Scholar
FARRIS-LÓPEZ, K., DENSLOW, J., MOSER, B. & PASSMORE, H. 2004. Influence of a common palm, Oenocarpus mapora, on seedling establishment in a tropical moist forest in Panama. Journal of Tropical Ecology 20:429438.Google Scholar
GENTRY, A. H. 1988. Tree species richness of upper Amazonian forests. Proceedings of the National Academy of Sciences USA 85:56159.Google Scholar
GILLMAN, L. N., WRIGHT, S. & OGDEN, J. 2002. Use of artificial seedlings to estimate damage of forest seedlings due to litterfall and animals. Journal of Vegetation Science 13:635640.Google Scholar
GILLMAN, L. N., GILLMAN, L. & OGDEN, J. 2003. Response of forest tree seedlings to simulated litterfall damage. Plant Ecology 169:5360.CrossRefGoogle Scholar
GILLMAN, L. N., OGDEN, J., WRIGHT, S., STEWART, K. & WALSH, D. 2004. The influence of macro-litterfall and forest structure on litterfall damage to seedlings. Austral Ecology 29:305312.Google Scholar
GREGORY, R. A. 1966. The effect of leaf litter upon establishment of white spruce beneath paper birch. Forestry Chronicle 42:251255.Google Scholar
KAHN, F. & DE GRANVILLE, J. J. 1992. Palms in forest ecosystems of Amazonia. Springer Verlag, Berlin. 214 pp.Google Scholar
LÓPEZ, J. C. & DIRZO, R. 2007. Floristic diversity of Sabal palmetto woodland: an endemic and endangered vegetation type from Mexico. Biodiversity and Conservation 16:807825.Google Scholar
MACK, A. 1998. The potential impact of small-scale physical disturbance on seedlings in a Papuan rain forest. Biotropica 30:547552.CrossRefGoogle Scholar
MÁRQUEZ, T., BIEJO, L. & RAMOS, F. 2010. Are biotic and abiotic factors and seedling mechanical damage in forest-edge fragments always different from the interior? Australian Journal of Botany 58:241247.Google Scholar
MCCARTHY, B. C. & FACELLI, J. M. 1990. Micro-disturbances in oldfields and forests: implications for woody seedling establishment. Oikos 58:5560.Google Scholar
PAUW, A., BAEL, S. A., PETERS, H. A., ALLISON, S. D., CAMARGO, J. L. C., CIFUENTES-JARA, M., GARCIA RESTOM, T., HEARTSILL-SCALLEY, T., MANGAN, S. A., NUNEZ-ITURRI, G., RIVERA-OCASIO, E., ROUNTREE, M., VETTER, S. & VOLKMER DE SASTILHO, C. 2004. Physical damage in relation to carbon allocation strategies of tropical forest tree saplings. Biotropica 36:410413.Google Scholar
PETERS, H., PAUW, A., SILMAN, M. & TERBORGH, J. 2004. Falling palm fronds structure Amazonian rainforest sapling communities. Proceedings of the Royal Society London B 271:S367369.Google Scholar
PORTELA, R. C. Q. & SANTOS, F. A. M. 2009. Mortality and mechanical damage of seedlings in different size fragments of the Brazilian Atlantic Forest. Tropical Ecology 50:267275.Google Scholar
SCARIOT, A. 2000. Seedling mortality by litterfall in Amazonian forest fragments. Biotropica 32:662669.Google Scholar
TAFFIN, G. D. 1998. Coconut. Macmillan Press, Hong Kong. 101 pp.Google Scholar
WANG, Y. & AUGSPURGER, C. 2006. Comparison of seedling recruitment under arborescent palms in two Neotropical forests. Oecologia 147:533545.Google Scholar
YOUNG, H. S., RAAB, T. K., MCCAULEY, D. J., BRIGGS, A. A. & DIRZO, R. 2010a. The coconut palm, Cocos nucifera, impacts forest composition and soil characteristics at Palmyra Atoll, Central Pacific. Journal of Vegetation Science 21:10581068.Google Scholar
YOUNG, H. S., MCCAULEY, D. J., DUNBAR, R. B. & DIRZO, R. 2010b. Plants cause ecosystem nutrient depletion via the interruption of bird derived spatial subsidies. Proceedings of the National Academy of Sciences USA 102:20722077.Google Scholar
YOUNG, H. S., MCCAULEY, D. J. & DIRZO, R. 2011. Differential responses to guano fertilization among tropical tree species with varying functional traits. American Journal of Botany 98:18.CrossRefGoogle ScholarPubMed
YOUNG, H. S., MCCAULEY, D. J., GUEVARA, R. & DIRZO, R. 2013. Density-dependent seed and seedling predation effects on plant diversity depend on scale. Oecologia 172:857867.CrossRefGoogle Scholar