Abstract: Soil basal respiration potential, metabolic quotient (qCO₂), and activities of urease, invertase and acid phosphomonoesterase were investigated in the root layer of 10, 40, and 90 yr old tea bushes grown on the same type of red soil. The soil daily basal respiration potential ranged from 36.23 to 58.52 mg·kg^-1 ·d^-1, and the potentials in the root layer of 40 or 90 yr old were greater than that of 10 yr old tea bushes.The daily qCO₂, ranging from 0.30 to 0.68, was in the reverse trend. The activities of test three enzymes changed differently with tea bushes' age. Urease activity in the root layer of all age tea bushes ranged from 41.48 to 47.72 mg·kg^-1 ·h^-1 and slightly decreased with tea bushes' age. Invertase activity was 189.29～363.40 mg·kg^-1 ·h^-1 and decreased with tea bushes' age, but its activity in the root layer of 10 year old tea bushes was significantly greater than that in the root layer soil of 40 or 90 year old tea bushes. Acid phosphomonoesterase activity (444.22～828.32 mg·kg^-1 ·h^-1) increased significantly with tea bushes' age. Soil basal respiration potential, qCO₂ and activities of 3 soil enzymes were closely related to soil pH, soil organic carbon, total nitrogen and C/Nratio, total soluble phenol, and microbial biomass carbon, respectively.

Key words: Soil basal respiration potential, Urease, Invertase, Acid phosphomonoesterase, Tea bushes, Red soil, fertilization management, organic fertilizer, arbuscular mycorrhizal fungal community, pyrosequencing, lime concretion black soil