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Soil respiration (R_S) is an important component of the C cycle because it contributes significant CO₂ emissions to the atmosphere that result from metabolism and respiration of its autotrophic and heterotrophic components. However, the relative importance of different biophysical controls that drive the variability of this flux and their influence along forest succession pathways is still unknown. We incorporate multiyear R_S, ecosystem flux and meteorological measurements in old-growth (OG), mid-secondary (MS) and early-secondary (ES) tropical dry forests (TDFs) with the goal of assessing the temporal variation of R_S and identifying the biophysical controls at each site by applying structural equation models (SEM). Along forest succession, R_S followed the pattern of precipitation events; we identified by the end of the wet season that R_S was sustained by a longer period at OG, while in MS and ES, R_S decreased according to the soil moisture availability. According to SEM, soil moisture and soil temperature exert an effect on the variability of R_S in all sites. However, we found that R_S was also controlled by the vapor pressure deficit at MS and gross primary production at OG and ES. Our results suggest that seasonality has a different impact on R_S along forest succession in TDFs found in northwestern Mexico and highlights the relevance of considering additional biophysical controls of R_S for a better understanding this critical process of the C cycle.