Figure 4.

Relationships between soil respiration (R _s, µmol CO₂ m⁻² s⁻¹) measured early in August and September, 2011, and soil organic C (SOC, g kg⁻¹), total N (TN, g kg⁻¹), the ratio of SOC and TN (SOC/TN ratio), microbial biomass C (MBC, mg kg⁻¹), microbial biomass N (MBN, mg kg⁻¹), dissolved organic C (DOC, mg kg⁻¹), dissolved organic N (DON, mg kg⁻¹), ammonium N (NH₄ ⁺-N, mg kg⁻¹), soil available N (SAN, mg kg⁻¹), the ratio of NH₄ ⁺-N and nitrate N (NH₄ ⁺-N/NO₃ ⁻-N ratio), and belowground root biomass (BGB, kg m⁻²), respectively. SOC, TN, MBC, and MBN data were obtained from Fu et al. [22].