Temperature sensitivity of respiration of forest soils is important for its responses to climate warming and for the accurate assessment of soil carbon budget. The sen-sitivity of temperature ( T i ) to soil respiration rate ( R s ), and Q 10 defined by e 10(ln Rs -ln a )/ Ti has been used extensively for indicating the sensitivity of soil respiration. The soil respi-ration under a larch ( Larix gmelinii ) forest in the northern Daxing'an Mountains, Northeast China was observed in situ from April to September, 2019 using the dynamic chamber method. Air temperatures ( T air ), soil surface temperatures ( T 0cm ), soil temperatures at depths of 5 and 10 cm ( T 5cm and T 10cm , respectively), and soil-surface water vapor con-centrations were monitored at the same time. The results show a significant monthly variability in soil respiration rate in the growing season (April–September). The Q 10 at the surface and at depths of 5 and 10 cm was estimated at 5.6, 6.3, and 7.2, respectively. The Q 10@10 cm over the period of surface soil thawing ( Q 10@10 cm, thaw = 36.89) were significantly higher than that of the growing season ( Q 10@10 cm, growth = 3.82). Furthermore, the R s in the early stage of near-surface soil thawing and in the middle of the growing season is more sensitive to changes in soil tempera-tures. Soil temperature is thus the dominant factor for season variations in soil respiration, but rainfall is the main con-troller for short-term fluctuations in respiration. Thus, the higher sensitivity of soil respiration to temperature ( Q 10 ) is found in the middle part of the growing season. The monthly and seasonal Q 10 values better reflect the responsiveness of soil respiration to changes in hydrometeorology and ground freeze-thaw processes. This study may help assess the sta-bility of the soil carbon pool and strength of carbon fluxes in the larch forested permafrost regions in the northern Daxing'an Mountains.

Lin Yang;Qiuliang Zhang;Zhongtao Ma;Huijun Jin;Xiaoli Chang;Sergey S.Marchenko;Valentin V.Spektor

College of Forestry and Da Xing'anling Forest Ecosystem Research Station of Inner Mongolia Autonomous Region,Inner Mongolia Agricultural University,Hohhot 010019,People's Republic of China;Research-Station of Permafrost Geo-Environment,Ministry of Education,Institute of Cold Regions Science and Engineering and School of Civil Engineering,Northeast Forestry University,Harbin 150040,People's Republic of China;State Key Laboratory of Frozen Soils Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,People's Republic of China;Geophysical Institute,University of Alaska Fairbanks,Fairbanks,AK 99775,USA;Laboratory of General Geocryology,Melnikov Permafrost Institute,Siberia Branch,Russian Academy of Sciences,Yakutsk,Russia 677010

林业研究（英文版）

[1]Lin Yang;Qiuliang Zhang;Zhongtao Ma;Huijun Jin;Xiaoli Chang;Sergey S.Marchenko;Valentin V.Spektor-.Seasonal variations in temperature sensitivity of soil respiration in a larch forest in the Northern Daxing'an Mountains in Northeast China)[J].林业研究（英文版）,2022(03):1061-1070

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