长白山典型森林生态系统土壤呼吸的季节动态

Seasonal Dynamics of Soil Respiration in Typical Forest Ecosystems of Changbai Mountains,China

利用Li-6400-09土壤呼吸室测定了生长季内(5—10月)长白山北坡不同海拔高度的4种森林生态系统土壤呼吸。结果表明:4种森林土壤总呼吸、异养呼吸和根系呼吸都存在明显的季节动态。阔叶红松林、红松云冷杉林的土壤总呼吸和异养呼吸都呈双峰型的季节动态,岳桦云冷杉林和岳桦林呈单峰型;阔叶红松林、红松云冷杉林和岳桦云冷杉林根呼吸都呈双峰型的季节动态,岳桦林呈单峰型;测定期间内,4种森林土壤总呼吸的季节变化范围是1.06～5.97μmol·m-2·s-1;根系呼吸对土壤总呼吸的贡献约为44.4%。

Soil respiration rates of four forest ecosystems on the north slope of Changbai Mountains were measured with Li-6400- 09 chamber during the growing season （ from May to October）. Results indicated that seasonal dynamics of total soil respi- ration, heterotrophie soil respiration and root respiration were obvious in the four forest ecosystems. Two-peak seasonal pat- terns of total soil respiration and heterotrophic soil respiration were found in the broadleaved Korean pine forest and Korean pine-spruce mixed forest, while one-peak seasonal patterns were observed in Betula ermanii-spruce mixed forest and B. er- manii forest. The root respiration in the broadleaved Korean pine forest, Korean pine-spruce mixed forest and B. ermanii- spruce mixed forest exhibited a two-peak seasonal pattern, and that in B. ermanii forest showed a one-peak pattern. The total soil respiration rates varied from 1.06 to 5.97μmol·m-2·s-1, and the contribution of root to total soil respiration was 44.4% in the four forest ecosystems during the measurement period.