title: Plant height-crown radius and canopy coverage-density relationships determine above-ground biomass-density relationship in stressful environments.
abstract: Debate continues in theoretical ecology over whether and why the scaling exponent of biomass-density (M-N) relationship varies along environmental gradients. By developing a novel geometric model with assumptions of allometric growth at the individual level and open canopy at the stand level, we propose that plant height-crown radius and canopy coverage-density relationships determine the above-ground M-N relationship in stressful environments. Results from field investigation along an aridity gradient (from eastern to western China) confirmed our model prediction and showed that the above-ground M-N scaling exponent increased with drought stress. Therefore, the 'universal' scaling exponents (-3/2 or -4/3) of the M-N relationship predicted by previous models may not hold for above-ground parts in stressful environments.
authors.affiliation: College of Life Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China.
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Dai
authors.forename: Xin
authors.initials: X
authors.lastname: Jia
authors.forename: Weiping
authors.initials: W
authors.lastname: Zhang
authors.forename: Yanyuan
authors.initials: Y
authors.lastname: Bai
authors.forename: Junyan
authors.initials: J
authors.lastname: Zhang
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Genxuan
authors.initials: G
authors.lastname: Wang
mesh_terms: D000465:Algorithms; D018533:Biomass; D002681:China; D017753:Ecosystem; D004777:Environment; D005843:Geography; D008954:Models, Biological; D015233:Models, Statistical; D008962:Models, Theoretical; D010802:Phylogeny; D018515:Plant Leaves / Q000033:anatomy & histology / Q000502:physiology*; D013696:Temperature