Restoration measures alter the regulation mechanism of soil respiration in the Wenchuan earthquake-affected area

Understanding the response of soil respiration (SR) to different restoration approaches after major earthquakes is essential for guiding ecosystem recovery and carbon management. We studied the effects of restoration measures on SR after the 2008 Wenchuan earthquake. We conducted the study using three types. of restoration measures (undisturbed sites, artificial restoration sites, and naturally recovered sites) in two climate zones including a dry hot climate (Weizhou Town) and a subtropical humid monsoon climate (Hanwang Town). We systematically monitored seasonal SR rates, hydrothermal factors (soil temperature and moisture), soil physicochemical properties, and microbial indicators during the period of 2015–2016. A total of 36 sampling quadrats were used to collect data, then variance partitioning analysis and stepwise regression were conducted to identify key driving factors of SR. Soil respiration rates were highest in undisturbed sites, intermediate in artificial restoration sites, and lowest in naturally recovered sites across both climate types. Although restoration measures significantly enhanced ecosystem recovery, SR rates in artificial restoration sites remained 20.59–41.21% lower than those in undisturbed sites. In dry-hot valley region, soil moisture was the dominant factor controlling SR (R 2 = 0.92), whereas artificial restoration improved hydrothermal coupling effects in the subtropical monsoon region (R 2 = 0.98). Naturally recovered sites had higher temperature sensitivity (Q₁₀ values ranging from 1.22 to 3.19) and greater ecosystem instability. Variance partitioning analysis indicated that SR in undisturbed sites was primarily dominated by biological factors (e.g., fungal biomass), whereas those in artificial restoration sites and naturally recovered sites showed biochemical compensation for physical limitations and relied on an enzymatic–chemical pathway, respectively. Our findings reveal the need for climate-adapted restoration strategies and offer a mechanistic understanding to guide post-earthquake soil recovery. • Soil respiration (SR) was determined 8 years after the Wenchuan earthquake. • Artificial restoration enhanced SR but remained lower than undisturbed sites. • Soil moisture was the dominant limiting factor for SR in the dry-hot valley. • Restoration soils shifted SR regulation from biological to biochemical pathways.