Response of Soil Respiration to Grazing in an Alpine Meadow at Three Elevations in Tibet

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].

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