关键词: 黄河源区, 温度, 团聚体, 有机碳矿化, Q₁₀, 高寒湿地

Abstract: Exploring the relationship between soil carbon sequestration and global warming is a critical issue. To clarify the characteristics of soil organic carbon (SOC) mineralization within aggregates in alpine wetlands in source region of the Yellow River,We conducted experiments to determine the SOC mineralization characteristics within aggregates across different particle sizes (>2 mm,2~0.25 mm,and <0.25 mm) in alpine wetland at 5℃,15℃ and 25℃ by alkali absorption method. The aim was to clarify the carbon sequestration features of soil aggregates in alpine wetlands under the context of global warming. The results showed that temperature wariation significantly affects the SOC mineralization within aggregates in alpine wetlands,and with mineralization amount of SOC in aggregates increasing at higher temperatures. The macro-aggregates (>2 mm and 2~0.25 mm) of alpine wetlands exhibited significantly higher SOC mineralization rates compared to micro-aggregates (<0.25 mm,P＜0.05). The temperature sensitivity coefficient (Q₁₀) of SOC mineralization within soil aggregates in alpine wetlands gradually increased with increasing temperature,and varied with particle size predominantly as (2~0.25 mm) > (>2 mm) > (<0.25 mm). These results suggest that rising temperature may diminish the carbon sequestration capacity of soil aggregates in alpine wetlands in source region of the Yellow River.

Key words: Source region of the Yellow River, Temperature, Aggregate, Organic carbon mineralization, Q₁₀, Alpine wetland