Abstract: Soil freezing-thawing cycle is very common in the regions at mid-high latitude and high altitude. During this cycle, soil physical properties, chemical composition, and microbial activities could be affected. Many researches indicated that the soils in the above-mentioned regions were the important source of greenhouse gases, and the accumulative emission of soil greenhouse gases during freezing-thawing cycle could contribute greatly to their total annual fluxes budget, especially of N₂O. Under global warming, the extension and frequency of soil freezing-thawing cycle could be increased in some regions, and the soil greenhouse gases emission in these regions would be enhanced, which in turn would promote global climate change. This paper summarized the research progress in the effects of freezing-thawing cycle on the greenhouse gases production and emission from soil, and the major related mechanisms. Some deficiencies in the study of soil freezing-thawing were pointed out, and the main issues in the future study were suggested.

Key words: Spatial scale, Aggregation, Majority rule, Random rule