This study aimed to investigate the biomass allocation pattern of four dominant shrubs, and to establish a prediction model for individual nutrient organ biomass, thus making an accurate assessment for biomass and carbon sequestration of plantations in the Jilantai salt lake area.

This study used four dominant shrubs (Hedysarum scoparium, Calligonum mongolicum, Haloxylon ammodendron and Tamarix chinensis) as research objects in the Jilantai salt lake area, and measured factors (plant height (H), basal diameter (D), crown width (C)) and their combination factors (CH, DH and D²H) were used as independent variables for optimal model fitting. We investigated the optimal biomass model for various nutrient organs and verified model fitting with accuracy.

1) 4 kinds of single dominant shrub biomass ranged from 28.19 to 43.44 kg in Jilantai salt lake area, with an average of 34.65 kg; Total biomass of single shrubs showed as follows: Hedysarum scoparium > Haloxylon ammodendron > Calligonum mongolicum > Tamarix chinensis; 2) The four dominant shrubs showed highly significant correlations between leaf biomass and branch biomass, leaf biomass and root biomass, and branch biomass and root biomass (P < 0.01); 3) Root-shoot ratios of four dominant shrubs ranged from 0.41 to 0.54, and the biomass of individual organs ranged from: branches > roots > leaves. The slopes of the fitted equations of the four dominant shrubs ranged from 0.78 to 1.23, with significant difference from 1, indicating that an allometric growth relationship between above- and underground biomass; 4) The R² values of different components shrub biomass prediction models were more than 0.825 for four dominant shrubs, and prediction accuracy of the optimal biomass model was more than 0.85, indicating good prediction accuracy.

The power and quadratic forms were optimal biomass models, and were suitable for an accurate estimation for biomass from specific tree species in Jilantai salt lake area.