Root architecture and allocation patterns of eight native tropical species with different successional status used in open-grown mixed plantations in Panama
- 246 Downloads
We investigated biomass allocation and root architecture of eight tropical species with different successional status, as classified from the literature, along a size gradient up to 5 m. We focused on belowground development, which has received less attention than aboveground traits. A discriminant analysis based upon a combination of allocational and architectural traits clearly distinguished functional types and classified species according to successional status at a 100% success rate. For a given plant diameter, the pioneer species presented similar root biomass compared to the non-pioneer ones but higher cumulative root length and a higher number of root apices. A detailed study on the root system of a sub-sample of three species showed that the most late-successional species (Tabebuia rosea) had longer root internodes and a higher proportion of root biomass allocated to the taproot compared to the other two species (Hura crepitans and Luehea seemannii). Most pioneer species showed a higher leaf area ratio due to a higher specific leaf area (SLA). We conclude that the functional differences between pioneer and non-pioneer tree species found in natural forests were maintained in open-grown plantation conditions.
KeywordsAllocation Allometry Root architecture Successional status Tropical plantation
This research was made possible by a Discovery Grant from NSERC (Canada) as well as help from the “Ministère de la Recherche, de la Science, et de la Technologie” of the province of Québec, Canada. LC was supported during 2007 by a “Juan de la Cierva” contract from the Spanish Ministry of Science and Education. E. Whidden, D. Ryan, O. Dermoly, G. Kunstler, Rob Guy and two anonymous reviewers provided many useful comments. We are indebted to the laboratory group of Evan DeLucia who discussed the paper at an early stage and provided feedback and to Suzy Lao, Richard Condit and Joe Wright who kindly provided the growth rate and seed mass data for the studied species collected in the BCI permanent plot. Finally, we would like to thank Jose Monteza who supervised and motivated the team of workers digging roots in the wet, clay rich soils of Sardinilla, Panama, and Lana Ruddick for English revision.
- Andrew RE, Newman EI (1973) Root density and competition for nutrients. Oecol Plant 5:319–334Google Scholar
- Caldwell MM, Richards JH (1986) Competing root systems: morphology and models of absorption. In: Givnish TJ (ed) On the economy of plant form and function. Cambridge University Press, Cambridge, pp 251–273Google Scholar
- Craven D, Braden D, Ashton MS, Berlyn GP, Wishnie M, Dent D (2007) Between and within-site comparisons of structural and physiological characteristics and foliar nutrient content of 14 tree species at a wet, fertile site and a dry, infertile site in Panama. For Ecol Manag 238:335–346CrossRefGoogle Scholar
- Croat TB (1978) Flora of Barro Colorado Island. Stanford University Press, Stanford, p 943Google Scholar
- Diaz S, Cabido M (2001) Vive la difference: plant functional diversity matters to ecosystem processes. Trends Ecol Evol 16:464–655Google Scholar
- Fitter AH (1987) An architectural approach to the comparative ecology of plant root systems. New Phytol 106:61–77Google Scholar
- Paz H (2003) Root/shoot allocation and root architecture in seedlings: variation among forest sites, microhabitats, and ecological groups. Biotropica 35:318–332Google Scholar
- Sanford RL, Cuevas E (1996) Root growth and rhizosphere interactions in tropical forests. In: Mulkey S, Chazdon RL, Smith AP (eds) Tropical Forest plant ecophysiology. Chapman and Hall, New York, pp 268–300Google Scholar
- Scherer-Lorenzen M, Potvin C, Koricheva J, Schmid B, Hector A, Bornik Z, Reynolds G, Schulze ED (2005) The design of experimental tree plantations for functional biodiversity research. In: Scherer-Lorenzen M, Korner Ch, Schulze ED (eds) Forest diversity and function: temperate and Boreal systems. Ecological Studies 176. Springer, Berlin, pp 347–376Google Scholar
- Veneklaas EJ, Poorter L (1998) Carbon partitioning strategies of tropical tree seedlings in contrasting light environments. In: Lambers H, Poorter H, Van Vuuren MMI (eds) Inherent variation in plant growth. Physiological mechanisms and ecological consequences. Backhuys Publishers, Leiden, pp 337–361Google Scholar