不同放牧退化程度的大针茅典型草原有机碳储量特征

Organic Carbon Storage Characteristics of Stipagrandis Typical Steppe in Different Grazing Degradation Degree

以内蒙古大针茅典型草原不同放牧退化程度样地为研究对象,通过分析地上植物、凋落物、根系、土壤中有机碳,研究草原植被—土壤系统有机碳储量变化规律,从碳储量角度为合理利用草原提供指导。研究结果表明：（1）不同退化程度典型草原地上植物有机碳储量为25.67-65.26g/m^2,凋落物有机碳储量为9.86-39.35g/m^2,且对照和轻度退化样地均显著高于中度和重度退化样地;（2）根系（0-40cm）有机碳储量为436.84-848.17g/m^2,土壤（0-40cm）有机碳储量为5773.37-6575.42g/m^2,且轻度退化样地均显著高于其他样地;（3）植被—土壤系统的有机碳储量为6245.75-7509.33g/m^2,从大到小依次为LD〉MD〉CK〉HD,87.56%-92.44%储存于土壤中,表明适度放牧利用有利于发挥草原生态系统的碳汇功能。

The research took Stipagrandis typical steppe in different grazing degradations as the research objects.The aboveground biomass,litter,belowground biomass and soil organic carbon were analyzed to study the organic carbon storage variation characteristics in vegetation soil systems.It provided theoretical basis for the reasonable utilization of grassland from the perspective of carbon storage.The results showed that the organic carbon storage was 25.67-65.26g/m^2 in aboveground biomass,9.86-39.35g/m^2 in litter.It was significantly higher in CK and light degradation（LD）than that in moderate degradation（MD）and high degradation（HD）.The organic carbon storage was 436.84-848.17g/m^2 in below ground biomass（0-40cm）,5773.37-6575.42g/m^2 in the soil in depth of 0-40cm,which in LD was significantly higher than that in other.The total organic carbon storage in the vegetation soil system was6245.75-7509.33g/m^2 under different grazing degradation degree.It was the largest in LD,followed by MD,CK,and HD.About 87.56%-92.44% of the total carbon storage was reserved in soil.Moderate grazing was beneficial to the carbon sequestration function of grassland ecosystem.