2025/12/02 by Yuxue Zhang, Zhaonan Ding, Xiaowei Guo +8 · 1 voice
Agricultural and Biological Sciences · Environmental Science · #Atmospheric and Environmental Gas Dynamics #Plant Water Relations and Carbon Dynamics #Soil Carbon and Nitrogen Dynamics
paper · pdf · doi:10.1007/s11676-025-01954-4
openalex created_date 2025/12/02 · openalex publication_date 2025/12/02 · openalex updated_date 2026/07/23
Abstract Assessment of soil organic carbon (SOC) dynamics is often inadequately represented in empirical measurements because of the significant heterogeneity in soil structure and physico-chemical properties. Partitioning soil carbon (C) emissions into autotrophic and heterotrophic respiration is essential for understanding CO 2 flux sources, but inconsistencies in their magnitude and responses reveal a knowledge gap in partitioning methodologies and their impact on respiration estimates. Utilizing data from an eight-yr field mesocosm study in a temperate oak forest, we computed C emissions from multiple components based on the metabolic theory. Our theoretical calculations of soil C emissions from various treatments were validated against periodic field measurements of soil respiration over an eight-year period. The optimized computations, which included annual precipitation data and accounted for biomass C from litter, roots, and microbes, closely aligned with field measurements of soil respiration across varying treatments. These results showed that fine root and microbial biomass jointly drove temporal variations in soil C emissions, while interannual precipitation variability plays a secondary role. This study confirms the feasibility of using metabolic theory to quantify soil C emissions and highlights the critical role of fine roots and soil microbial biomass, emphasizing the need for a deeper understanding of these factors in SOC budget assessments. Graphical abstract