Mechanisms underlying the growth-survival trade-off among tree species in relation to edaphic specialization

University Of Nebraska-Lincoln, Lincoln NE

Investigators

Abstract

All organisms face tradeoffs in they way they allocate resources. Trees, for example, can allocate resources in ways that promote rapid growth (e.g., more leaves with higher nitrogen content) or in ways that protect them from herbivores (e.g., thorns, defensive chemicals). This project addresses those tradeoffs and asks if they contribute to specialization of tree species on different soil types in an extremely diverse Bornean rain forest. Environmental gradients in the availability of resources may contribute disproportionately to tree diversity because tree species often specialize on particular habitats. A reciprocal transplant experiment, combined with a defoliation treatment and observations of resource allocation in the field, will be used to test for differences in allocation to growth, storage, and defense among trees on different soil types. Plant available mineral nutrients and water will be quantified to document the variation in belowground resources. In addition to advancing knowledge of the determinants of fundamental life history trade-offs, this research will improve understanding of tree species' responses to belowground resources and of mechanisms whereby soil-specific tree species distributions arise in forests. This project is an international collaboration with several worthy broader impacts. Several local Malaysians and Iban (an indigenous people) will be trained in data collection and management. This research will provide valuable information on forest regeneration and the environmental requirements of tree species, which can be applied directly in forest conservation and reforestation efforts in Borneo. Public lectures and development of secondary school education materials will communicate the broader implications of this work and emphasizing the vital functions of tropical forests and the ecological services they provide to human society.