Biomass Modeling for Caragana microphylla in Inner Mongolia

Based on the mensuration biomass data of the common shrub species,Caragana microphylla,in Inner Mongolia of China,the individual compatible above and underground biomass models and root-toshoot ratio model were developed firstly using the approach of nonlinear error-in-variable simultaneous equations. The community-level whole biomass models based on mean canopy area and stem density or canopy closure were constructed. The results showed that: 1) the canopy area was the most important factor related to shrub biomass,and the next was number of stems; 2) the determination coefficient of individual aboveground biomass model based on canopy area and number of stems was close to 0. 7,but that of underground biomass model was relatively lower,even less than 0. 5; 3) the mean prediction precisions of individual above and below-ground biomass models were about 90%,and that of whole biomass model was more than 92%,indicating that the biomass models could be applied in shrub biomass estimation for the species in Inner Mongolia; 4) the approach of deriving community-level whole biomass models from individual whole biomass model could provide a reference for modeling community-level biomass for shrub species.