In:
Journal of Forestry Research, Springer Science and Business Media LLC, Vol. 33, No. 3 ( 2022-06), p. 1061-1070
Kurzfassung:
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 sensitivity 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 respiration 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 concentrations 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 temperatures. Soil temperature is thus the dominant factor for season variations in soil respiration, but rainfall is the main controller 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 stability of the soil carbon pool and strength of carbon fluxes in the larch forested permafrost regions in the northern Daxing’an Mountains.
Materialart:
Online-Ressource
ISSN:
1007-662X
,
1993-0607
DOI:
10.1007/s11676-021-01346-4
Sprache:
Englisch
Verlag:
Springer Science and Business Media LLC
Publikationsdatum:
2022
ZDB Id:
2299615-1
SSG:
23
