摘要：Carbon dioxide (CO 2 ) concentration under snow was examined through two winter seasons at a 3100 m elevation subalpine site in the Snowy Range of Wyoming. CO 2 was monitored every half hour at the soil/snow interface, and at about −25 cm soil depth the second year, in a meadow and in an adjacent forest. CO 2 under snow in the meadow was significantly higher than that in the forest. CO 2 at −25 cm depth in the soil was significantly higher than soil surface CO 2 . The CO 2 under snow increased rapidly as snow melted and snowmelt began in the spring. CO 2 concentration under snow depended primarily on amount occurring during the previous 24 or 48 h. However, CO 2 concentration was related to snow depth and soil temperature, and indirectly to several seasonal environmental factors, especially solar radiation. Solar radiation, snow depth, and CO 2 under snow all increase concurrently as the winter season progresses. CO 2 flux was consistently higher in the meadow than in the forest and increased in late winter for both sites. Snow covered subalpine meadows and forests contribute considerable amounts of CO 2 to the atmosphere in the winter.
