Distribution and Nutrient Contents of Fine Roots in the Fushan Subtropical Broadleaf Forest in Taiwan

The biomass and nutrient contents of fine roots were investigated and estimated in the Fushan subtropical broadleaf forest in northeastern Taiwan. The result indicated that the fine root density decreased with increasing soil depth. In 0~30 cm of soil, the biomass of fine roots was approximately 677 g m-2 for a size of < 2 mm, 335 g m-2 for 2~5-mm fine roots, and 61 g m-2 for the necromass. The total length of fine roots of < 2 mm was approximately 3860 m m-2, but only 120 m m-2 for 2~5-mm roots. The fine root biomass in Fushan is higher than that in temperate forests and similar to that in tropical rain forests. This may mainly be due to the lower available P as a result of torrential rains, which promotes the accumulation of fine roots. At the same time, as fine roots accumulate a large amount of N and P, they play an important role in the storage of nutrients in the ecosystem.