Abstract: To clarify the effects of shading and soil types on growth and nutrient content of Firmiana platanifolia seedlings, we measured the growth, nutrient accumulation and allocation characteristics of F. platanifolia seedlings in an experiment followed two split plot test design. There were four different shading levels: natural light (A₁), 50% shading (A₂), 75% shading (A₃), and 95% shading (A₃), and four soil types: acid purple soil (B₁), alkali purple soil (B₂), red soil (B₃) and yellow soil (B₄). The results showed that the growth and nutrient accumulation of F. platanifolia were significantly affected by shading, soil types, and their interaction (P<0.05). With increasing shading intensity, the height of F. platanifoliaseedlings gradually increased. F. platanifoliawere highest but with smallest basal diameter under A₄B₂ treatment. The basal diameter and total biomass of F. platanifoliaseedlings were the highest under A₃B₂ treatment. Likewise, the total accumulation of K, Ca, Mg and Na reached its maximum value under A₃B₂ treatment. Shading treatment increased the allocation of K, Ca and Mg to leaves and reduced their allocation to roots. Meanwhile, F. platanifoliashowed greater use efficiency of K, Ca, Mg and Na under A₃B₂ treatment. In conclusion, 75% shading and alkaline purple soil could improve the growth, biomass and nutrient accumulation ofF. platanifoliaseedlings, but excessive shading had a certain inhibitory effect on seedling growth. Our findings will help to select the suitable key cultivation and management strategy, and provide support for nutrient management in F. platanifolia seedlings.

Key words: shading, soil type, Firmiana platanifolia, accumulation, allocation ratio, use efficiency.