关键词: 土壤呼吸, 自养呼吸, 异养呼吸, 温度敏感性, 中山草甸

Abstract: Aims Characterizing the variation of soil carbon flux components in the Zhongshan meadow of Wuyi Mountain, the highest distributed meadows in the subtropical region of southeastern China, and exploring their relationships with environmental factors and temperature sensitivity (Q10) holds significant importance. This research contributes to the accurate estimation of regional soil carbon income and expenditure, refining the understanding of carbon fluxes in Zhongshan meadows. Methods From May 2020 to April 2021, the LI-8100 CO2 flux analyzer was utilized to systematically monitor the soil respiration rate (RS) in the meadow located at the summit of Wuyi Mountain. Additionally, the root exclusion technique was applied to differentiate between the autotrophic respiration rate (RA) and the heterotrophic respiration rate (RH). Important findings (1) The dynamics of RS, RA and RH exhibited bimodal curves, with consistently higher values observed from May to October compared to other months. Notably, RA displayed greater variability than RH throughout the year. RA accounts for 45% of RS. (2) Multi-model comparative analysis suggests that the temperature (T) of the Zhongshan meadow soil in Wuyi Mountain exhibits an exponential growth correlation with soil respiration and its components. The ranking of Q10 values for soil respiration and its components was RA (Q10 = 1.96) > RS (Q10 = 1.94) > RH (Q10 = 1.67). While soil moisture (W) had a certain effect on RS, no significant relationship was observed between RA and RH. The T and W two-factor models demonstrated a better fit for RS compared to the single factor models jointly explaining 48% of the variation in RS. In conclusion, both T and W are important environmental factors influencing soil respiration in Zhongshan meadow. In Zhongshan Meadow of Wuyi Mountain, soil respiration is dominated by heterotrophic respiration, with autotrophic respiration displaying higher sensitivity to temperature changes. Notably, soil temperature and humidity emerge as important environmental factors affecting soil respiration in Zhongshan Meadow of Wuyi Mountain, respiration is inhibited by low temperatures and high humidity. This study helps to enhance the understanding of the seasonal dynamics and influencing factors of soil respiration and its components in the Zhongshan meadow, and also provides practical support for the study of regional soil carbon flux and carbon cycle. Key words soil respiration; autotrophic respiration; heterotrophic respiration; temperature sensitivity (Q10); Zhongshan meadow

Key words: soil respiration, autotrophic respiration, heterotrophic respiration, temperature sensitivity (Q10), Zhongshan meadow