Influence of lime, nitrification inhibitors and soil infusion on nitrification in peat

Abstract

lx an th ate, KEtX) an d soil in fu sio n o n N mineralization in a n acid p eat was stu d ied . Release o f NH^-N in c re a sed significantly with pH. Accumulation of 599 to 803 mg NH^-N/kg occurred a t pH 3.4 an d 6.5, respectively on day 15 an d th e value decreased to 205 to 381 m g /k g a t 25 days an d th en ag a in increased to 304 to 471 m g /k g a t pH 3.4 and 6.5 with 100 mg N-Serve/kg, respectively a t the end of incubation. The initial a c cum u la tio n was du e to mineralization of orgainc N p re s e n t in th e peat. The d e c re a s e in the in te rm ed ia te stage might be asso ciated with microbial immobilization. Nitrification o c cu rred a fte r a long lag p h a se . The v a lu e s of (NO^+NOgl-N were 0.1 to 0 .6 a n d 11.3 to 15.1 m g /k g a t 25 an d 35 days of incubation, respectively. Generation of 11.4 to 15.1 an d 10.7 to 14.2 mg (NO^+NO^l-N'/kg in the presence of 100 m g /k g N-Serve an d KEtX. respectively provides evidence th a t n itrification c an proceed a t pH 3.4 where a n acid-adapted stra in is operative.