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Advantages for biochars used in soil improvement have been proposed to their nutrients release and sorption characteristics which strongly depend on their production conditions. N 2 -flow and air-limited pyrolysis are two different widely-applied oxygen-limited pyrolysis methods for producing biochars, however, their different effects on nutrients release and sorption characteristics of biochars remains unknown. In this study, bamboo derived biochars pyrolyzed in N 2 -flow (BC-N 2 ) and air-limited environments (BC-Air) at the temperature of 150~750 °C were used to compare the release and sorption of nitrogen and phosphorous nutrients. The results showed that release of nitrogen and phosphorous in BC-Air were always greater than those in BC-N 2 , the maximum nitrogen and phosphorous release of BC-Air (0.65 mg/g at 750 °C) is about 7.7 times of that of BC-N 2 (0.084 mg/g at 450 °C). Both BC-N 2 and BC-Air had no/little sorption of phosphate. Meanwhile, the sorption capacity of ammonium nitrogen on BC-Air (1.83 ~ 4.67 mg/g) was always greater than that on BC-N 2 (0.23 ~ 1.34 mg/g) at the pyrolysis temperature of 300 ~ 750 °C. Phosphorous-containing minerals in ash was an enhancing factor for the release of phosphorous and sorption of ammonium nitrogen on BC-Air. Furthermore, with increasing pyrolysis temperature, the release amount of phosphorous from BC-Air and the sorption capacity of ammonium nitrogen on BC-Air increased. The results show that high pyrolysis temperature combined with air-limited environment produced biochars are optimal for nutrients enhancement and retention., Competing Interests: Declaration of Competing Interest The authors declare that there is no conflict of interest regarding the publication of this article., (Copyright © 2019 Elsevier B.V. All rights reserved.)