[Detection of Influencing Factors of Spatial Variability of Soil Respiration in Pangquangou Nature Reserve]

Soil respiration is an important process in maintaining global carbon balance. Taking the Pangquangou Nature Reserve as the research area, based on the field measurement of soil respiration (R_s) data combined with altitude (ELE), soil temperature (T), soil moisture (SWC), normalized vegetation index (NDVI), slope (slope), soil total carbon (C), total nitrogen (N), and soil bulk density (BD), we analyzed the main driving forces and interactions of R_s spatial differentiation by using the geographic detector model. The results showed that:① the spatial variation of R_s and its influencing factors in the study area was moderate. The R_s was significantly positively correlated with NDVI, T, and N (P<0.01) and negatively with ELE, slope, and SWC (P<0.01). The R_s was significantly correlated with BD(P<0.05) but not with C(P>0.05). ② The multivariate linear model composed of NDVI and T explained 64.3% of R_s spatial variation. ③ ELE, T, and NDVI were the dominant driving forces of R_s spatial differentiation in the study area, which could explain 64%, 59%, and 48% of the spatial variability. ④ The interaction of the two factors enhanced the explanatory power of R_s spatial differentiation, and the maximum interaction factors were ELE∩BD (q=0.73), and T∩slope (q=0.74), respectively. Therefore, in the process of R_s estimation, combined with topographical and environmental conditions, the interaction between multiple factors should be considered.