Carbon stable isotopic composition of karst soil CO_2 in central Guizhou,China

• 作 者: 郑乐平
• 机 构: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sc
• 出 处: Science in China(Series D:Earth Sciences)
• 发表日期: 1999年06期
• 关键词: isotopic karst seasonal microbes Guizhou vegetation isotope fractionation grass

The δ13 values of soil CO2 are less than that of atmosphere CO2 in the karst area. On the soil-air interface, the δ13 vlaues of soil CO2 decrease with the increase in soil depth; below the soil-air interface, the δ13C values of soil CO2 are invariable. The type of vegetation on the land surface has an influence on the δ13C values of soil CO2 Due to the activity of soil microbes, the δ13C values of soil CO2 are variable with seasonal change in grass. Isotopic tracer indicates that atmosphere CO2 has a great deal of contribution to soil CO2 at the lower parts of soil profile.

The δ13 values ​​of soil CO2 are less than that of atmosphere CO2 in the karst area. On the soil-air interface, the δ13 vlaues of soil CO2 decrease with the increase in soil depth; below the soil-air interface, the δ13C values ​​of The type of vegetation on the land surface has an influence on the δ13C values ​​of soil CO2 due to the activity of soil microbes, the δ13C values ​​of soil CO2 are variable with seasonal change in grass. Isotopic tracer indicates that atmosphere CO2 has a great deal of contribution to soil CO2 at the lower parts of soil profile.