Dataset Information

Deciduous and evergreen trees differ in juvenile biomass allometries because of differences in allocation to root storage.

ABSTRACT:

Background and aims

Biomass partitioning for resource conservation might affect plant allometry, accounting for a substantial amount of unexplained variation in existing plant allometry models. One means of resource conservation is through direct allocation to storage in particular organs. In this study, storage allocation and biomass allometry of deciduous and evergreen tree species from seasonal environments were considered. It was expected that deciduous species would have greater allocation to storage in roots to support leaf regrowth in subsequent growing seasons, and consequently have lower scaling exponents for leaf to root and stem to root partitioning, than evergreen species. It was further expected that changes to root carbohydrate storage and biomass allometry under different soil nutrient supply conditions would be greater for deciduous species than for evergreen species.

Methods

Root carbohydrate storage and organ biomass allometries were compared for juveniles of 20 savanna tree species of different leaf habit (nine evergreen, 11 deciduous) grown in two nutrient treatments for periods of 5 and 20 weeks (total dry mass of individual plants ranged from 0·003 to 258·724 g).

Key results

Deciduous species had greater root non-structural carbohydrate than evergreen species, and lower scaling exponents for leaf to root and stem to root partitioning than evergreen species. Across species, leaf to stem scaling was positively related, and stem to root scaling was negatively related to root carbohydrate concentration. Under lower nutrient supply, trees displayed increased partitioning to non-structural carbohydrate, and to roots and leaves over stems with increasing plant size, but this change did not differ between leaf habits.

Conclusions

Substantial unexplained variation in biomass allometry of woody species may be related to selection for resource conservation against environmental stresses, such as resource seasonality. Further differences in plant allometry could arise due to selection for different types of biomass allocation in response to different environmental stressors (e.g. fire vs. herbivory).

SUBMITTER: Tomlinson KW

PROVIDER: S-EPMC3718220 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Deciduous and evergreen trees differ in juvenile biomass allometries because of differences in allocation to root storage.

Tomlinson Kyle W KW van Langevelde Frank F Ward David D Bongers Frans F da Silva Dulce Alves DA Prins Herbert H T HH de Bie Steven S Sterck Frank J FJ

Annals of botany 20130801 3

<h4>Background and aims</h4>Biomass partitioning for resource conservation might affect plant allometry, accounting for a substantial amount of unexplained variation in existing plant allometry models. One means of resource conservation is through direct allocation to storage in particular organs. In this study, storage allocation and biomass allometry of deciduous and evergreen tree species from seasonal environments were considered. It was expected that deciduous species would have greater all ...[more]

PMID: 23877001

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Dataset Information

Deciduous and evergreen trees differ in juvenile biomass allometries because of differences in allocation to root storage.

Background and aims

Methods

Key results

Conclusions

Publications

Deciduous and evergreen trees differ in juvenile biomass allometries because of differences in allocation to root storage.

Similar Datasets

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