Above- and belowground biomass of Artemisia ordosica communities in three contrasting habitats of the Mu Us desert, northern China

摘要

We developed and compared allometric equations describing leaf, branch, and fruit biomass at the branch level, and leaf, branch, fruit and coarse root biomass at the whole plant level for Artemisia ordosica plants growing on fixed, semi-fixed and shifting dunes of the Mu Us desert. At the branch level, branch diameter significantly correlated with leaf, branch and fruit biomass. The allometric relationships predicting leaf, branch and fruit biomass significantly differed among the different dune types. At the whole plant level, crown area significantly correlated with leaf, branch, fruit and coarse root biomass. The allometric relationships predicting leaf and fruit biomass significantly differed among the different dune types. Stand total biomass was 339.9, 178.8 and 25.0 gm~(-2) in fixed, semifixed and shifting dunes, respectively. Stand biomass of leaves, branches, fruits, coarse roots, and fine roots (1-2 mm and ＜1 mm in diameter) significantly decreased, while the below- to aboveground biomass ratio significantly increased from the fixed to the shifting dunes, with intermediate values for the semi-fixed dunes. Vertical distribution of fine root biomass also significantly differed among the three dune types. There was a significant and positive correlation between stand fine root biomass and stand crown area. These results will help to predict how the species will adapt to habitat changes through adjustments in morphology and biomass of different compartments under arid environmental conditions.