The role of fine‐root mass, specific root length and lifespan in tree performance: a whole‐tree exploration
| Autor: | Natasa Kiorapostolou, Frank J. Sterck, Jasper van Ruijven, Liesje Mommer, Monique Weemstra, Jorad de Vries |
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| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
Field data fine roots Plant Ecology and Nature Conservation Biology root economics spectrum 010603 evolutionary biology 01 natural sciences Root length Statistics Root mass whole-plant model Bosecologie en Bosbeheer functional traits Ecology Evolution Behavior and Systematics carbon balance Life span Interspecific competition PE&RC Forest Ecology and Forest Management Trait Centre for Crop Systems Analysis Plantenecologie en Natuurbeheer tree performance Tree species 010606 plant biology & botany |
| Zdroj: | Functional Ecology 34 (2020) 3 Functional Ecology, 34(3), 575-585 |
| ISSN: | 0269-8463 |
| Popis: | 1. The root economics spectrum (RES) hypothesis predicts that fast-growing tree species have short-lived roots with high specific root length (SRL) to allow rapid resource uptake, and opposite trait expressions for slow-growing species. Yet, the mixed support for this hypothesis suggests that trees can adopt alternative strategies to increase resource uptake, besides an increase in SRL. 2. We combined a novel mechanistic whole-tree model and empirical fine-root data of ten tree species to test the effects of one of these alternative strategies, notably increasing fine-root mass, on the tree’s net C gain (used here as a proxy for tree performance), and to assess how fine-root lifespan influences the relative importance of SRL and fine-root mass for the C balance of trees. 3. Our results indicate that accounting for the short lifespan of high-SRL roots has important implications for explaining tree performance and the role of roots herein. Without considering their faster turnover, high-SRL roots and low fine-root mass resulted in the highest performance as predicted from the RES. Yet, when their higher turnover rates were accounted for, a high fine-root mass and low SRL lead to the highest performance. Both our model outcomes and field data further show a negative relationship between SRL and fine-root mass through which species aim to realise a similar root length density. This trade-off further indicates how high a SRL and low fine-root mass as well as opposite trait values can both lead to a positive C balance in a similar environment. 4. Our study may explain why high-SRL roots do not necessarily lead to the fastest tree growth as often hypothesised and demonstrates the importance of fine-root mass in combination with fine-root lifespan for explaining interspecific differences in tree performance. More generally, our work demonstrates the value of identifying and investigating different belowground strategies across species from a whole-plant modelling perspective, and identifies the relationship between SRL, fine-root biomass and lifespan as an important functional dimension to variation in species’ performance. |
| Databáze: | OpenAIRE |
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