摘要
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.
基金
the National Key Research and Development Plan of China(2016YFA0600801)
the Hundred Talents Program of Shaanxi Province(A289021701)
the Natural Science Basic Research Plan in Shaanxi Province of China(2018JZ3002)
the Special Fund from the State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau(A314021403-C9)
the Double First Class University Plan of NWSUAF(Z102021829).
