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Leaf nitrogen (N) and phosphorus (P) concentrations constrain photosynthetic and metabolicprocesses,growth and the productivity of plants.Their stoichiometry and scaling relationships regulate the allocation of N and P from subcellular to organism,and even ecosystem levels,and are crucial to the modelling of plant growth and nutrient cycles in terrestrial ecosystems.Prior work has revealed a general biogeographic patte of learN and P stoichiometric relationships and shown that leafN scales roughly as two-thirds the power of P.However,determining whether and how leafN and P stoichiometries,especially their scalingexponents,change with functional groups and environmental conditions requires further verification.In this study,we compiled a global data set and documented the global leafN and P concentrations and the N∶P ratios by functional group,climate zone and continent.The global overall mean leafN and P concentrations were 18.9 mg g-1 and 1.2 mg g-1,respectively,with significantly higher concentrations in herbaceous than woody plants (21.72 mg g-1 vs.18.22 mg g-1 for N;and 1.64 mg g-1 vs.1.10 mg g-1 for P).Both leafN and P showed higher concentrations at high latitudes than low latitudes.Among six continents,Europe had the highest N and P concentrations (20.79 and 1.54 mg g-1) and Oceania had the smallest values (10.01 and 0.46 mg g-1).These numerical values maybe used as a basis for the comparison of other individual studies.Further,we found that the scaling exponent varied significantly across different functional groups,latitudinal zones,ecoregions and sites.T-he exponents of herbaceous and woody plants were 0.659 and 0.705,respectively,with significant latitudinal pattes decreasing from tropical to temperate to boreal zones.At sites with a sample size ≥ 10,the values fluctuated from 0.366 to 1.928,with an average of 0.841.Several factors including the intrinsic attributes of different life forms,P-related growth rates and relative nutrient availability of soils likely account for the inconstant exponents of learN vs.P scaling relationships.