Forest soils serve as critical terrestrial carbon sinks. While broad hydrothermal controls on soil respiration (R
s) are established, uncertainties persist regarding high-frequency temporal dynamics and moisture-dependent variations in temperature sensitivity (Q
10). Specifically, conventional reliance on discrete, clear-day sampling obscures
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Forest soils serve as critical terrestrial carbon sinks. While broad hydrothermal controls on soil respiration (R
s) are established, uncertainties persist regarding high-frequency temporal dynamics and moisture-dependent variations in temperature sensitivity (Q
10). Specifically, conventional reliance on discrete, clear-day sampling obscures how precipitation disrupts diurnal patterns. To address this, we continuously monitored R
s and environmental factors in two Northeast Chinese mixed forests (Korean pine,
Pinus koraiensis (KP), and Dahurian larch,
Larix gmelinii (DL)) to quantify weather-driven daily dynamics and carbon fluxes. Precipitation primarily drove daily variability, but more importantly, it reshaped day–night asymmetry. Under clear-day conditions, R
s exhibited a consistent daytime-dominant pattern, with daytime fluxes being significantly higher than nighttime fluxes (
p < 0.05). However, precipitation events fundamentally neutralized this asymmetry, resulting in no significant day–night differences across most phenological stages. Annual R
s effluxes (759 and 965 g C m
−2 yr
−1 for KP and DL, respectively) lacked significant inter-stand or temporal variations. Seasonal emissions peaked unimodally in July, with the non-growing season contributing merely 5%–8%. Notably, spring freeze–thaw R
s in the KP stand surged interannually by 143%. While R
s correlated positively with temperature (
p < 0.001), Q
10 was co-regulated by forest stand and moisture. Under moderate moisture, the KP stand’s Q
10 (2.72) was significantly lower than the DL stand’s (3.81); however, this divergence neutralized under low moisture. Consequently, soil moisture acts as both a direct R
s driver and a fundamental regulator of its temperature sensitivity. These empirical findings provide critical data to calibrate forest carbon models, improving predictions of soil carbon feedbacks under future climate scenarios.
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