对贡嘎山高山生态系统2 013~3 650 m海拔梯度上的土壤呼吸速率特征、时空变化规律及其与土壤温湿度、土壤有机碳、全氮等的关系进行了分析,结果表明:随海拔的升高,土壤呼吸速率先逐渐增加然后降低,土壤呼吸最大值出现在海拔2 750 m处。土壤呼吸速率在8月初最高,12月初最低。随着季节的变化,一天中土壤呼吸速率最高和最低值出现的时间也会发生变化。8月土壤呼吸值日变化范围最大,最低和最高值分别出现在9:30和15:00,5—7月以及9—11月土壤呼吸速率的最低值和最高值分别出现在7:30点和13:30。进入秋冬季(10—12月)土壤呼吸速率日变化特征减弱,尤其是进入12月后无明显日变化特征。土壤温度是影响土壤呼吸时空变异的主要因子;土壤有机碳和全氮含量也是影响土壤呼吸的因子;土壤湿度并不是影响土壤呼吸速率的贡嘎山高山生态系统重要因素。

Temporal and spatial variation of soil respiration along an altitudinal gradient ( 2 013 ～ 3 650 m a． s． l． ) in east slopeof Gongga Mountain，Sichuan province，China，and its relationships with soil temperature，soil moisture， soil organic carbon and total nitrogen content werestudied in this study． Results indicated that soil respiration
ratefirst increased and then decreased with theincreaseof altitude． Themaximum of soil respiration was observed at sites in 2 750 m a． s． l． Temporally，thesoil respiration ratewas highest in August and was lowest in December，so does thedaily variations of soil respiration Theminimum and maximum of daily soil respiration in August  ereseparately observed at 9: 30 and 15: 00，whilethat in September to November，wereobserved at 7: 30 and 13: 30，respectively． Thedaily variations of soil respiration weresmall in winter ( October to December) ，especially thosein December
werenegligible． Soil temperatureweremain factors to influencing temporal and spatial variation of soil respiration， Soil organic carbon and soil total nitrogen content werefactors influencing soil respiration，Soil moisturewas not influenced soil respiration ratein Gongga Mountain forest ecosystem ．