TY  - JOUR
AU  - Baraloto, C.
AU  - Bonal, D.
AU  - Goldberg, D.E.
PY  - 2006//
TI  - Differential seedling growth response to soil resource availability among nine neotropical tree species
T2  - J. Trop. Ecol.
JO  - Journal of Tropical Ecology
SP  - 487
EP  - 497
VL  - 22
PB  - CAMBRIDGE UNIV PRESS
KW  - biomass allocation
KW  - Dicorynia
KW  - drought stress
KW  - Eperua
KW  - French Guiana
KW  - Goupia
KW  - Jacaranda
KW  - plasticity
KW  - Qualea
KW  - Recordorylon
KW  - relative growth rate
KW  - Sextonia
KW  - soil phosphorus
KW  - specific leaf area
KW  - Virola
N2  - Although the potential contribution to tropical tree species coexistence of niche differentiation along light gradients has received much attention, the degree to which species perform differentially along soil resource gradients remains unclear. To examine differential growth response to soil resources, we grew seedlings of nine tropical tree species at 6.0% of full sun for 12 mo in a factorial design of two soil types (clay and white sand), two phosphate fertilization treatments (control and addition of 100 mg P kg(-1)) and two watering treatments (field capacity and water limitation to one-third field capacity). Species differed markedly in biomass growth rate, but this hierarchy was almost completely conserved across all eight treatments. All species grew more slowly in sand than clay soils. and no species grew faster with phosphate additions. Only Eperua grandiflora and E. falcata showed significant growth increases in the absence of water limitation. Faster-growing species were characterized by high specific leaf area, high leaf allocation and high net assimilation rate but not lower root allocation. Slower-growing species exhibited greater plasticity in net assimilation rate. suggesting that tolerance of edaphic stress in these species is related more to stomatal control than to whole-plant carbon allocation. Although relative growth rate for biomass was correlated with both its physiological and morphological components. interspecific differences were best explained by differences in net assimilation rate across six of the eight treatments. A suite of traits including high assimilation and high specific leaf area maintains rapid growth rate of faster-growing species across a wide gradient of soil resources, but the lack of plasticity they exhibit may compromise their survival in the poorest soil environments.
SN  - 0266-4674
N1  - ISI:000239975200001
ID  - Baraloto_etal2006
ER  -