Characteristics of biomass allocation of Cenchrus pauciflorus under arid and irrigated habitats

Characteristics of biomass allocation of Cenchrus pauciflorus were investigated in arid and irrigated habitats in Korqin sandy land. Ramet height and biomass, biomass of root, stem, leave, spikes and sheath were measured respectively. The study showed that ramet height of C. pauciflorus in the wet condition was 41.2 cm, which was significantly taller than that in the arid condition, 33.7 cm. In the irrigated habitat, the biomass of spikes was 1.8 times of that in arid habitat. Within the two habitats, the biomass of root, stem, leave and sheath were positively significantly correlated with ramet biomass (P0.01) and marked a regular pattern of power function of y=axb; the biomass of root, stem, leave and sheath were also positively significantly correlated with each other (P0.05), which accords with the linear rule of y=ax+b. In the wet condition, the growth rate of module biomass is higher than that in the arid condition with the increasing of ramet biomass. The analysis concluded that C. pauciflorus took the strategy of survival in the arid habitat, and the countermeasure of competition and breeding growth in the wet habitat.