Abstract:

The energy variation pattern in the fine roots turnover process of Pinus tabulaeformis and Quercus aliena var. acuteserrata natural forests in Qinling mountains were studied systematically. The results showed that the energy loss was followed by an attenuation index pattern in the process of fine root decomposition. The decomposition coefficient of Quercus aliena var. acuteserrata forest was 0.0031 and its turnover rate was 0.35 time·a^-1. The decomposition coefficient of Pinus tabulaeformis forest was 0.0024 and its turnover rate was 0.48 time·a^-1. The average annual storage energy in living fine roots of Pinus tabulaeformis forest was 119.43×10⁶ kJ·hm^-2 and the average annual energy loss in dead fine roots was 21.84×10⁶ kJ·hm^-2 which was 31.7% of litter energy loss. Similarly, the average annual storage energy in living fine roots of Quercus aliena var.Acuteserrata forest was 172.70×10⁶ kJ·hm^-2 and the average annual energy loss in dead fine roots was 58.31×10⁶ kJ·hm^-2 which was 62.8% of litter energy loss.

Key words: Pinus tabulaeformis forest, Quercus aliena var. acuteserrata forest, Fine roots, Turnover, Energy