Stem and leaf functional traits allow successional classification in six pioneer and non-pioneer tree species in Tropical Moist Broadleaved Forests

Abstract The present study was carried out to analyse the leaf functional traits of co-occurring evergreen and deciduous tree species in a tropical dry scrub forest. This study also intended to check whether the species with contrasting leaf habits differ in their leaf trait plasticity, responding to the canopy-infestation by lianas. A total of 12 leaf functional traits were studied for eight tree species with contrasting leaf habits (evergreen and deciduous) and liana-colonization status (Liana+ and Liana−). In the liana-free environment (L−), evergreen trees had significantly higher specific leaf mass (LMA) and leaf dry matter content (LDMC) than the deciduous species. Whereas, the deciduous trees had higher specific leaf area (SLA) and mass-based leaf nitrogen concentration (Nmass). The leaf trait-pair relationship in the present study agreed to the well-established global trait-pair relationships (SLA Vs Nmass, Lth Vs SLA, Nmass Vs Lth, Nmass Vs LDMC, LDMC Vs SLA). There was no significant difference between L+ and L− individuals in any leaf functional traits studied in the deciduous species. However, evergreen species showed marked differences in the total chlorophyll content (Chlt), chlorophyll b (Chlb), SLA, and LMA between L+ and L− individuals of the same species. Deciduous species with the acquisitive strategy can have a competitive advantage over evergreen species in the exposed environment (L−) whereas, evergreen species with shade-tolerant properties were better acclimated to the shaded environments (L+). The result revealed the patterns of convergence and divergence in some of the leaf functional traits between evergreen and deciduous species. The results also showed the differential impact of liana colonization on the host trees with contrasting leaf habits. Therefore, liana colonization can significantly impact the C-fixation strategies of the host trees by altering their light environment. Further, the magnitude of such impact may vary among species of different leaf habits. The increased proliferation of lianas in the tropical forest canopies may pose a severe threat to the whole forest carbon assimilation rates.

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Spatial structure of genetic variation and primary succession in the pioneer tree species Antirhea borbonica on La Reunion

Molecular Ecology ◽

10.1111/j.1365-294x.2005.02502.x ◽

2005 ◽

Vol 14 (5) ◽

pp. 1575-1584 ◽

Cited By ~ 25

Author(s):

I. LITRICO ◽

J. RONFORT ◽

R. VERLAQUE ◽

J. D. THOMPSON

Keyword(s):

Genetic Variation ◽

Spatial Structure ◽

Tree Species ◽

Primary Succession ◽

La Réunion ◽

Pioneer Tree Species ◽

Pioneer Tree

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Loss of desiccation tolerance during germination in neo-tropical pioneer seeds: implications for seed mortality and germination characteristics

Seed Science Research ◽

10.1017/s0960258507837755 ◽

2007 ◽

Vol 17 (4) ◽

pp. 273-281 ◽

Cited By ~ 19

Author(s):

Matthew I. Daws ◽

Sheina Bolton ◽

David F.R.P. Burslem ◽

Nancy C. Garwood ◽

Christopher E. Mullins

Keyword(s):

Desiccation Tolerance ◽

Tree Species ◽

Pioneer Tree Species ◽

Pioneer Tree ◽

Seed Mortality ◽

Progress Curve ◽

Seed Population ◽

Germination Characteristics ◽

Fixed Proportion ◽

Number Of Seeds

AbstractOrthodox, desiccation-tolerant seeds lose desiccation tolerance during germination. Here, we quantify the timing of the loss of desiccation tolerance, and explore the implications of this event for seed mortality and the shape of germination progress curves for pioneer tree species. For the nine species studied, all seeds in a seedlot lost desiccation tolerance after the same fixed proportion of their time to germination, and this proportion was fairly constant across the species (0.63–0.70). The loss of desiccation tolerance after a fixed proportion of the time to germination has the implication that the maximum number of seeds in a seedlot that can be killed by a single drying event during germination (Mmax) increases with an increasing time to 50% germination (t50) and an increasing slope of the germination progress curve. Consequently, to prevent the seed population from becoming highly vulnerable to desiccation-induced mortality, species with a greater t50 would be expected to have a shallower germination progress curve. In conclusion, these data suggest that the loss of desiccation tolerance during germination may constitute a significant, but previously unexplored, source of mortality for seeds in seasonal environments with unpredictable rainfall.

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