贡嘎山亚高山林地碳的累积和消散

The carbon accumulation and dissipation features of sub-alpine woodland in Mt. Gongga

Based on biomass investigations, soil respiration and plant photosynthesis measurement ofdominant trees in Hailuogou valley of Mt. Gongga, Southwest China, the carbon (C) storage,absorption and release for several typical woodlands in sub-alpine zones have been discussed. ForAbies fabri forest of 3,000 m above sea level, the C storage amount is 177.4 t/ha for above-groundbiomass and 143.2 t/ha for soil below-ground biomass. The annual gross C fixed by vegetationphotosynthesis is 20-24 t/ha. The C release by canopy respiration is 3.0-5.5 t/ha for arbors and 10-19t/ha for surface soil and roots. The annual net C fixed of forest ecosystem is about 6.0-7.1 t/ha. Atlower elevations, the amount of C released by woodlands is higher than that of woods at higherelevations. The C fixed capacity of renewed forest with middle-aged trees is higher than that of matureforest. Before becoming over-matured forest, woodland is an important sink of C whereas bareland inwoods is the source of atmospheric C.