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全球碳循环研究表明．在北半球中纬度地带可能存在一个陆地生志汇（植被和土壤）。中国黄土分布在北半球中纬度，在CO2未知汇的研究中很可能具有重要作用。通过自制钻机对北京斋堂黄土剖面（L2上部～L1）进行了不同层位（深度）的垂直或水平打钻，利用毛细管负压原理采集到游离气体并进行了主要温室气体CP2、CH4、N2O的浓度和CO2的碳、氧同位素组成分析。此外，还分析了土样的碳酸盐含量及其碳、氧同位素组成。初步研究结果表明，黄土剖面中主要温室气体浓度远比大气中高：CO2浓度为1434．4×10－6～2458．6×10－6，是大气中的3．8～6．5倍；N2O浓度为472．2×10－9～763．9×10－9，是大气中的1．3～2．1倍；CH4浓度在剖面上部与大气中相似，但在下部为13．1×10－6～24．8×10-6，为大气中的5．4～10．2倍。斋堂黄土剖面中的破酸盐含量为1．55％～9．75％，CO2浓度与碳酸盐含量成正比关系。尽管黄土－古土壤序列富含碳酸盐，但需进一步开展黄土中的CO2浓度及碳同位素工作，以便了解黄土中CO2在全球碳循环中的地位和作用。
Global carbon cycle research shows. In the northern hemisphere mid-latitudes there may be a land biota (vegetation and soil). Loess in China is located in the mid-latitudes of the northern hemisphere and is likely to play an important role in the study of unknown CO2 sinks. Vertical or horizontal drilling at different horizon (depth) of Zhaotang loess section (upper L2 ~ L1) of Beijing Zhaotong was carried out by self-made drilling rig. The free gas was collected by capillary negative pressure principle and the main greenhouse gases CP2, CH4, N2O Concentration and carbon and oxygen isotopic compositions of CO2. In addition, the carbonate content and its carbon and oxygen isotopic compositions were also analyzed. Preliminary results show that the concentration of major greenhouse gases in the loess section is much higher than that in the atmosphere: CO2 concentration is 1434.4 × 10-6 ~ 2458.6 × 10-6, which is 3.8-6.5 times that of the atmosphere; N2O Concentrations of 472.2 × 10-9 ~ 763.9 × 10-9, 1.3 to 2.1 times the atmosphere; CH4 concentration in the upper part of the profile similar to the atmosphere, but in the lower part of 13.1 × 10 -6 to 24.8 × 10 -6, which is 5.4 to 10.2 times that of the atmosphere. Zhaotang loess section in the broken acid salt content of 1.55% ~ 9.75%, CO2 concentration and carbonate content is proportional to the relationship. Although the Loess-Paleosol sequence is rich in carbonate, further studies are needed on CO2 concentration and carbon isotope in loess in order to understand the role and position of CO2 in loess in the global carbon cycle.