how much does the rhizosphere releases co2

The rhizosphere is a major source of soil CO₂ emissions due to respiration by roots and associated microbes. The amount varies based on root biomass, microbial activity, soil moisture, and temperature. Typically, rhizosphere respiration contributes 30–60% of total soil CO₂ efflux. It can spike during peak growth or after fertilization. Quantifying exact CO₂ release needs chamber or tracer-based field experiments.