Total ecosystem respiration (TER) is the major contributor to atmospheric carbon inputs. Investigating the characteristics of cropland TER is essential for understanding the global carbon balance. To better understand the seasonal dynamics of eddy covariance system-based TER and chamber-based soil respiration (SR), as well as their controlling factors, we conducted an in-depth analysis of two-year summer maize and winter wheat rotation systems from June 2020 to June 2022 in the Guanzhong Plain combined with nonlinear regression and Person correlation. The average TER values of the summer maize and winter wheat growing seasons were 1164.0 and 672.7 \( \text{g C }{\text{m}}^{\text{-2}}\) , respectively; in addition, the SR/TER ratios were 0.58 and 0.84, respectively. The average determination coefficients of the exponential curves of SR and soil temperature at the 10-cm depth ( \( {\text{T}}_{\text{s10}}\) ) over the summer maize and winter wheat growing seasons were 0.45 and 0.73, respectively; whereas the temperature sensitivities of SR ( \( {\text{Q}}_{\text{10}}\) ) were 2.56 and 2.05, respectively. Air temperature ( \( {\text{T}}_{\text{air}}\text{),} {\text{T}}_{\text{s10}}\) , and leaf area index (LAI) were the dominant controlling factors of TER in winter wheat growing seasons, while the dominant factor in summer maize seasons of TER was LAI. Moreover, \( {\text{T}}_{\text{air}}\) and \( {\text{T}}_{\text{s10}}\) were the main factors affecting the SR of the winter wheat growing seasons, followed by the LAI. Results showed a significant negative correlation between SR and LAI in the summer maize growing seasons (p < 0.01). This study provides theoretical support for an in-depth understanding of the mechanisms controlling carbon emissions from croplands in the Guanzhong Plain.
