大兴安岭白桦林土壤呼吸动态变化

Soil Respiration Dynamic of Betula Platyphylla Forest in Da xing'an Mountains

通过对大兴安岭地区白桦林生长季(8-11月)土壤呼吸的动态研究,发现大兴安岭地区白桦样地生长季(8-11月)土壤表面二氧化碳通量(Rs)和异养呼吸(Rh)动态特征相似,随着季节推移,二氧化碳通量逐渐减少,10月以后减小幅度变小,土壤呼吸量趋于稳定。8月份,Rs和Rh达到最大值,分别为4.46μmol·m-2·s-1和3.83μmol·m-2·s-1,整个生长季,各个月份异养呼吸占总土壤呼吸的比例不同,8月最大为85.87%,9月最小为70.20%。对Rs、Rh与T、W进行相关性分析,大兴安岭地区白桦样地Rs与T具有极显著的相关关系(R=0.787),Rs与W相关关系不显著(R=0.207);Rh与T具有极显著的相关关系(R=0.859),Rh与W具有极显著的相关关系(R=0.717)。季节的差异对于土壤呼吸的速率影响不同。

Soil respiration is the result of the soil environment combined effects of biology and biochemistry,is a major part of terrestrial ecosystem carbon cycle dynamics of this paper birch Da xing＇an Mountain region growing season（ July to November） of soil respiration,soil respiration quantified component and further explore its impact factor,found Da xing＇an Mountain region birch plots growing season（ August to November） soil surface CO2flux（ Rs） and heterotrophic respiration（ Rh） dynamic characteristics were similar,with the increase of time,CO2 flux gradually decreased after October reduced the magnitude smaller,soil respiration stabilized. August,Rs,and Rh maximum,respectively 4. 46μmol·m- 2·s- 1and 3. 83μmol·m- 2·s- 1,the entire growing season,different each month heterotrophic respiration proportion of total soil respiration,a maximum of 85. 87% in August,September minimum of 70. 20%. For Rs,Rh and T,W correlation analysis,Mountains region birch plots Rs highly significant correlation（ R = 0. 787） and T,Rs and W relationship was not significant（ R = 0. 207）; Rh and T has highly significant correlation（ R = 0. 859）,Rh and W has a highly significant correlation（ R = 0. 717）. Large differences in soil respiration in different seasons.