Distribution patterns of aboveground and underground biomass in desert grasslands in Xinjiang

The allocation of biomass in grassland ecosystems is essential for research on carbon storage and cycling in ecosystems. To explore the distribution patterns of aboveground and underground biomass of desert grasslands in Xinjiang, its distribution characteristics were analysed and evaluated. The results showed that: 1) Aboveground and underground biomass of desert grasslands ranged from 15.16 to 164.67 and 1109.50 to 3284.00 g·m⁻², respectively. The root-shoot ratios ranged from 16.09 to 98.42. Therefore, the belowground biomass was greater than the aboveground biomass. 2) The power function relationship between aboveround and underground biomass in the desert grasslands was y = 535.35x^0.2916 (R² = 0.51, P < 0.01), and the slope of the fit (using logarithmic equation) was 0.45, which was significantly different from 1. Thus, an allometric growth relationship between the aboveground and underground biomass was established. 3) Approximately 76.05% of the total underground biomass of the desert grasslands is distributed at a soil depth of 0－50 cm, showing that most roots cluster in this upper layer of soil. Moreover, the distribution curve of underground biomass of the desert grasslands conforms to the power function. The study of biomass distribution patterns in desert grasslands is necessary to accurately assess desert grassland carbon stocks and develop a deeper understanding of the carbon cycle in dryland grasslands.