关键词: 优先流, 枫香麻栎混交林, 碳运移

Abstract: In order to investigate the hydrological characteristics of soil preferential flow with different rainfall intensities and its effect on carbon transport, the mixed forest of Liquidambar formosana and Quercus acutissima on Zijin Mountain of Nanjing was studied. Three simulated rainfall intensities of 10 mm，25 mm，and 50 mm were illustrated by field dying tracer method. The effects of preferential flow on soil organic carbon, inorganic carbon, water-soluble organic carbon and water-soluble inorganic carbon were studied by calculating the contribution rate of preferential flow path. The results showed that: ① Dye coverage generally and length index of preferential flow increased with the increasing of simulated rainfall intensity. When the simulated rainfall intensity was 10 mm, 25 mm and 50 mm, the maximum dye coverage was 15.33%, 37.01% and 69.14%, respectively, and the maximum depth of soil priority flow was 27.59 cm, 35.83 cm and 42.00 cm. ② There was a significant positive correlation between the area ratio of soil priority flow and simulated rainfall intensity, a significant positive correlation with the contribution of preferential flow to water-soluble organic carbon, and a significant positive correlation between the development of preferential flow and the migration of water-soluble organic carbon in soil. There was a significant negative correlation with the evaluation index of priority process degree. ③ With the increase of rainfall intensity, the development of preferential flow could be enhanced, and the contribution rate of preferential flow to the transport of water-soluble organic carbon was 15.06%~64.04%.

Key words: preferential flow pathways (PFPs), Liquidambar formosana and Quercus acutissima mixed forest, carbon transport