中国科学院水利部水土保持研究所机构知识库

Background: Metabolic scaling theory predicts that plant productivity and biomass are both size-dependent.
However, this theory has not yet been tested in plant roots.
Methods: In this study, we tested how metabolic scaling occurs in plants using a comprehensive plant root dataset
made up of 1016 observations from natural habitats. We generated metabolic scaling exponents by logtransformation
of root productivity versus biomass.
Results: Results showed that the metabolic scaling exponents of fine root (< 2mm in diameter) productivity versus
biomass were close to 1.0 for all ecosystem types and functional groups. Scaling exponents decreased in coarse
roots (> 2mm in diameter).
Conclusions: We found isometric metabolic scaling in fine roots, a metabolically active organ similar to seedlings
or saplings. Our findings also indicate a shift in metabolic scaling during plant development. Overall, our study
supports the absence of any unified single constant scaling exponent for metabolism-biomass relationships in
terrestrial plants, especially for forests with woody species.
Keywords: Allometry, Biomass, Metabolic scaling, Plant roots, Productivity