Distribution of CO_2 in soil air affected by vegetation in the Shilin national park

摘要

This paper studies the CO_2 distribution of soil atmosphere in the Shilin National Park. The measurement sites were chosen according to different topographic features and different vegetations. Seven measurement sites on 3 cross sections were chosen to pass through 3 karstic depressions or on the slopes of depressions. All measurement results show soils with pH values lower than 7.0(from 5.4 to 6.6). There are 2 cases of the pH cases for pH values of sol in different topographic features: the pH values of 2 profiles on the ridges or upper slopes of depression are lower than those in the depression; and the pH values of 2 soil profiles on the slopes of depressions are higher than those in the depressions.