Abstract: On the assumption of real single population biomass growth being resulted from dynamic equilibrium of supply and demand of nutrients, a model of single population biomass growth is developed. The model looks like Cui-Lawson's model, but its three parameters are differed from Cui-Lawson's model's biological meaning. The model can answer under which conditions some growth patterns of single population biomass appear, and can give the relation of single population biomass growth with population itself's intrinsic growth rate and decomposition condition of nutrient recycling. The establishment and interpretation of this model are audio-visual.

Key words: Dynamic equilibrium, Supply and demand of nutrient, Model, Sinlge population biomass growth, Cui-Lawson's model, niche characteristics, environmental interpretation, Loess Plateau hilly region, abandoned grassland